Swim trunks designed for the characteristics of the breaststroke

Abstract

The present application relates to a kind of trunks designed for the characteristics of breaststroke, belong to swimming clothing field, at least one of the problems such as poor drag reduction effect, low energy transfer efficiency, insufficient support performance, limited flexibility etc. when existing swimsuit is applied to breaststroke is solved.A kind of trunks designed for the characteristics of breaststroke, is made of stretch fabric, at least cover thigh and part of hip when wearing, with the side close to skin as the reverse side;The trunks include local pressurized area, tension band and joint seam.The trunks of the present application reduce the movement resistance in breaststroke, improve the energy conversion efficiency, provide sufficient muscle support, and ensure the flexibility of movement.

Description

Technical Field

[0001] This invention relates to the field of swimming apparel technology, and more particularly to swimming trunks designed specifically for the characteristics of breaststroke. Background Technology

[0002] High-performance competitive swimsuits, as core equipment for enhancing swimming performance, currently adopt a universal design concept in mainstream products, providing comprehensive solutions for various swimming strokes through biomimetic textures and overall compression technology. However, this design approach, geared towards general scenarios, increasingly reveals its technological limitations when dealing with the unique biomechanical characteristics of breaststroke.

[0003] The propulsion mechanism of breaststroke relies primarily on the large-amplitude kicking and squeezing motions of the hip and knee joints. This unique movement pattern places contradictory demands on swimsuit performance: it requires ample freedom of movement in the hip and thigh areas while simultaneously needing strong support in the torso to suppress muscle vibration and maintain body streamline. Current general-purpose swimsuits employ a homogeneous compression design, which, while providing basic support, makes excessive compromises on mobility in key areas, directly limiting the range and power output of the kick. Furthermore, their support structure is not optimized for the unique torso undulation trajectory of breaststroke, resulting in significant energy loss during transmission.

[0004] Therefore, developing a competitive swimsuit that is specifically designed for breaststroke, while maintaining core support performance and fully releasing the freedom of joint movement, and optimizing drag reduction and energy transfer efficiency, is of great significance for promoting technological innovation in competitive swimming equipment, improving the performance level of the sport, and promoting the high-quality development of the sports technology industry. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to provide swim trunks designed for the characteristics of breaststroke, in order to solve at least one of the problems existing in swimwear when applied to breaststroke, such as poor drag reduction effect, low energy transfer efficiency, insufficient support performance, and limited flexibility.

[0006] The objective of this invention is achieved through the following technical solution: The present invention provides swimming trunks designed for the characteristics of breaststroke, which are made of stretch fabric. When worn by the human body, the stretch fabric covers at least part of the thighs and buttocks, with the side close to the skin being the reverse side. The swim trunks include a localized pressure zone, tension bands, and seams; The tension band is fixedly installed on the reverse side of the swim trunks, and the design position of the tension band is determined based on pressure cloud map and sports biomechanics; the tension band includes a biceps femoris chain support band and / or a rectus femoris chain support band; The localized pressurization area uses multi-layered fabric, and the design location of the localized pressurization area is determined based on the pressure cloud map; The design area and design direction of the joint are determined based on the surface streamline diagram.

[0007] Furthermore, the biceps femoris chain support band starts from the anterior superior iliac spine, obliquely passes through the sartorius muscle, turns to the lateral posterolateral region of the thigh, passes successively through the tensor fasciae latae, the middle segment of the iliotibial band and the biceps femoris muscle, and finally terminates at the upper edge of the lateral popliteal fossa.

[0008] Furthermore, the rectus femoris chain support band starts from the lower back, passes sequentially through the gluteus maximus, the upper segment of the iliotibial band, the anterior border of the tensor fasciae latae, and then extends longitudinally along the rectus femoris to the inner side of the trouser leg above the knee.

[0009] Furthermore, the biceps femoris chain support band includes a first biceps femoris chain support band and a second biceps femoris chain support band that are symmetrical on both sides. The first biceps femoris chain support band and the second biceps femoris chain support band pass through the following six key points or key areas in sequence: A1-anterior superior iliac spine; B1-tensor fasciae latae; C1-middle and lower segment of iliotibial band; D1-middle segment of biceps femoris belly; E1-junction area of ​​biceps femoris tendon-muscle belly; F1-upper edge of lateral popliteal fossa.

[0010] Furthermore, the rectus femoris chain support band includes a first rectus femoris chain support band and a second rectus femoris chain support band that are symmetrical on both sides; the first rectus femoris chain support band and the second rectus femoris chain support band pass through the following seven key points or key areas in sequence: A2 - the sacrospinalis muscle in the midline region of the lower back; B2 - the middle section of the upper edge of the gluteus maximus; C2 - the upper section of the iliotibial tract; D2 - the anterior edge of the tensor fasciae latae; E2 - the proximal end of the rectus femoris; F2 - the middle section of the rectus femoris belly; G2 - the area above the knee, on the inner side of the patella, above the trouser leg.

[0011] Furthermore, the local pressure area includes a first pressure enhancement area covering the perineal area, a second pressure enhancement area covering the hip, buttocks and hamstring muscles, and a third and fourth pressure enhancement areas symmetrically distributed on both sides covering the vastus lateralis muscle.

[0012] Furthermore, the seam includes: The seams are symmetrically placed on both sides in the groin area; The seams, which are symmetrically arranged on the left and right sides and intersect with the thigh root area, extend longitudinally downward along the inner thigh and end at the lower edge of the trouser hem. A vertical seam is placed in the middle of the buttocks; And the seam located at the waistband, parallel to the upper edge of the waistband and encircling it.

[0013] Furthermore, the symmetrical seams located in the groin region include: a first seam and a second seam extending obliquely downwards from the anterior superior iliac spine to the perineal region.

[0014] Furthermore, the outer fabric of the swim trunks in the first pressure-enhancing area and / or the second pressure-enhancing area is a textured fabric, and the design position of the textured fabric is determined based on the surface shear stress diagram; the textured fabric is a warp-knitted fabric with a vertical stripe structure formed by jacquard process.

[0015] Furthermore, the periodic interval of the vertical stripes is 6-10 mm; And / or, the width of the vertical stripes is 1-2.5 mm; And / or, the thickness variation of the vertical stripes does not exceed 40%-60% of the maximum thickness of the textured fabric; And / or, the maximum thickness of the textured fabric does not exceed 0.5-1.0 mm.

[0016] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: (1) To address the problem of poor drag reduction effect of existing swimsuits when applied to breaststroke, this invention achieves specialized drag reduction for breaststroke through the design of localized pressurization zones guided by pressure cloud maps. Specifically, this invention guides the design location of localized pressurization zones based on pressure cloud maps during breaststroke movements. Combined with research on the characteristics of breaststroke movements and human anatomy, a multi-layered fabric structure is used in specific localized pressurization zones to specifically optimize the body contour, making the body lines more streamlined. This effectively reduces pressure drag during breaststroke, fundamentally solving the problem of incompatibility between general drag reduction design and the unique fluid characteristics of breaststroke, and achieving precise drag reduction for breaststroke-specific sports.

[0017] (2) To address the issues of low energy transfer efficiency and insufficient support performance, this invention achieves a performance breakthrough through the synergistic effect of tension bands and localized pressure zones. Specifically, this invention, based on research into the characteristics of breaststroke posture and human anatomy, fixes tension bands at specific locations on the reverse side of the swim trunks. This allows the tension bands to precisely conform to the core muscle groups involved in breaststroke, providing directional support and elastic feedback during movement, promoting the coordinated contraction and force transmission of the core muscle groups, and significantly improving energy transfer efficiency. Simultaneously, the localized pressure zones designed on the swim trunks, together with the tension bands, form a synergistic support system, providing stable support for the core muscle groups, effectively suppressing muscle vibration, and solving the problem of insufficient support performance in general swimsuits. This structural design, based on tension cloud maps and the biomechanical characteristics of breaststroke, achieves a simultaneous improvement in support performance and energy transfer efficiency while maintaining freedom of movement.

[0018] (3) To address the issue of limited flexibility, this invention achieves a balance between support and flexibility through zoned functional design. Specifically, the swim trunks are made of stretchable fabric, ensuring basic freedom of movement while maintaining overall coverage. This invention guides the design area and direction of the seams based on the surface streamline diagram under the breaststroke posture, and combines research on the characteristics of the breaststroke posture and human anatomy to arrange seams in specific locations on the swim trunks. This effectively avoids high-activity areas and prevents restriction of key joint movements. At the same time, tension bands and localized pressure areas are precisely set in specific locations, achieving zoned functional optimization. While ensuring the support performance of the core area, it maximizes the freedom of movement of key parts such as the thigh root and hip joint, thereby effectively solving the contradiction between high-intensity support and movement flexibility.

[0019] (4) In some preferred embodiments, the present invention guides the design position of textured fabric by using the surface shear stress diagram under the breaststroke posture, and combines the study of the breaststroke posture characteristics and human anatomical structure, and uses textured fabric on the outer layer of swim trunks in specific areas, which can achieve more precise flow control, suppress the formation of flow separation zone, and thus effectively reduce fluid resistance.

[0020] (5) In some preferred embodiments, by controlling the specific direction and / or position of tension bands, local pressure areas, seams, textured fabrics, and material parameters of some key tension bands and specific areas of fabric, the various sections of the swimsuit and tension bands can achieve better synergistic effects, and further realize the synergistic optimization and improvement of drag reduction, energy transfer efficiency, support performance, and flexibility.

[0021] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0022] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0023] Figure 1 A schematic diagram of the structure of swimming trunks designed for the characteristics of breaststroke in an embodiment of the present invention (I), (a) is the front view, (b) is the left side view, and (c) is the rear view; Figure 2The following is a schematic diagram (II) of the structure of the swimming trunks designed for the characteristics of breaststroke in an embodiment of the present invention: (a) is the front view, (b) is the left side view, and (c) is the rear view. Figure 3 The following is a schematic diagram (III) of the structure of the swimming trunks designed for the characteristics of breaststroke in an embodiment of the present invention: (a) is the front view, (b) is the left side view, and (c) is the rear view. Figure 4 The following is a schematic diagram (IV) of the structure of the swimming trunks designed for the characteristics of breaststroke in an embodiment of the present invention: (a) is the front view, (b) is the left side view, and (c) is the rear view. Figure 5 The following is a schematic diagram (V) of the structure of the swimming trunks designed for the characteristics of breaststroke in an embodiment of the present invention: (a) is the front view, (b) is the left side view, and (c) is the rear view; Figure 6 This is a schematic diagram of the movement cycle of the breaststroke in an embodiment of the present invention; Figure 7 This is a schematic diagram of the characteristic postures of the breaststroke in an embodiment of the present invention; Figure 8 The pressure cloud diagrams corresponding to the characteristic postures of the breaststroke in the embodiments of the present invention are shown, where a is a top view, b is a top view, and c is a side view. Figure 9 This is a partial enlarged view of the pressure cloud map corresponding to the characteristic posture of the breaststroke in an embodiment of the present invention, wherein a is a bottom view, b is a top view, and c is a side view; Figure 10 The following are surface streamline diagrams corresponding to the characteristic postures of the frog swimming in an embodiment of the present invention, wherein a is a bottom view, b is a top view, and c is a side view; Figure 11 This is a partial enlarged view of the surface streamline diagram corresponding to the characteristic posture of the frog swimming in an embodiment of the present invention, wherein a is a bottom view, b is a top view, and c is a side view; Figure 12 The above are surface shear stress diagrams corresponding to the characteristic swimming postures of the frog swimming in the embodiments of the present invention, where a is a bottom view, b is a top view, and c is a side view; Figure 13 This is a partially enlarged view of the surface shear stress diagram corresponding to the characteristic swimming posture of the frog swimming in an embodiment of the present invention, wherein a is a bottom view, b is a top view, and c is a side view; Figure label: 1-First biceps femoris chain support band; 2-Second biceps femoris chain support band; 3-First rectus femoris chain support band; 4-Second rectus femoris chain support band; 5-First pressure reinforcement zone; 6-Second pressure reinforcement zone; 7-Third pressure reinforcement zone; 8-Fourth pressure reinforcement zone; 9-First joint; 10-Second joint; 11-Third joint; 12-Fourth joint; 13-Fifth joint; 14-Sixth joint; A1 - Anterior superior iliac spine; B1 - Tensor fasciae latae; C1 - Middle and lower segment of iliotibial tract; D1 - Middle segment of biceps femoris belly; E1 - Biceps femoris tendon-muscle belly junction area; F1 - Upper border of lateral popliteal fossa; A2 - Sacrospinalis muscle in the midline region of the posterior lumbar region; B2 - Middle segment of upper border of gluteus maximus; C2 - Upper segment of iliotibial tract; D2 - Anterior border of tensor fasciae latae; E2 - Proximal end of rectus femoris; F2 - Middle segment of rectus femoris belly; G2 - Upper border of patella on the medial side of the trouser leg above the knee. Detailed Implementation

[0024] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0025] To address the aforementioned issues, this invention combines the structural design of swimming trunks with swimming posture characteristics. Through posture analysis, anatomical features, computational fluid dynamics flow characteristics calculation and resistance analysis of breaststroke characteristic postures, a competitive swimming trunks structure adapted to the breaststroke posture characteristics is designed, including the distribution of tension bands inside the swimming trunks, the trend of seam lines, the location of pressure reinforcement areas, and the reasonable layout of different fabrics.

[0026] The present invention provides swimming trunks designed for the characteristics of breaststroke, which are made of stretch fabric. When worn by the human body, the stretch fabric covers at least part of the thighs and buttocks, with the side close to the skin being the reverse side. The swim trunks include a localized pressure zone, tension bands, and seams; The tension band is fixedly installed on the reverse side of the swim trunks, and the design position of the tension band is determined based on pressure cloud map and sports biomechanics; the tension band includes a biceps femoris chain support band and / or a rectus femoris chain support band; The localized pressurization area uses multi-layered fabric, and the design location of the localized pressurization area is determined based on the pressure cloud map; The design area and design direction of the joint are determined based on the surface streamline diagram.

[0027] Compared to existing technologies, this invention addresses the limitations of the "universal design" of mainstream international swimsuits. Through systematic analysis of the unique anatomical features of breaststroke, such as trunk twisting and kicking movements, combined with CFD numerical simulations of breaststroke postures, it achieves for the first time a precise adaptation of the swim trunk structure to the specific characteristics of breaststroke. Based on this, the invention systematically matches tension bands, seams, and localized pressure areas with the breaststroke motion trajectory, completing a technological upgrade from "general-purpose" to "specialized." Practical application shows that the swim trunks of this invention achieve significant performance improvements in breaststroke: optimized streamlined design effectively reduces drag; precise tension band layout improves energy conversion efficiency; zoned pressure design provides ample muscle support; and it maintains sufficient freedom of joint movement, ensuring flexibility.

[0028] The design of the tension band position in this invention fully considers the anatomical characteristics of the breaststroke. Specifically, based on research into the characteristics of the breaststroke's movement posture and the structure of human anatomy, the leg kick is the main propulsive force for the body. As the anatomical characteristics of the breaststroke show, the leg kick mainly involves the flexion and extension of the hip and knee joints, with the rectus femoris and biceps femoris being the primary muscles involved. Therefore, the structural design of the breaststroke swimsuit focuses on assisting the leg kick, with a key consideration being providing support for the rectus femoris and biceps femoris. This additional support helps improve the efficiency of muscle contraction.

[0029] Based on research into the characteristics of the breaststroke posture and the anatomical structure of the human body, this invention further proposes the following specific tension band structure design scheme: Specifically, the biceps femoris chain support band starts from the anterior superior iliac spine, obliquely passes through the sartorius muscle, turns to the lateral posterolateral region of the thigh, passes successively through the tensor fasciae latae, the middle segment of the iliotibial band and the biceps femoris muscle, and finally terminates at the upper edge of the lateral popliteal fossa.

[0030] Specifically, the rectus femoris chain support band starts from the lower back, passes through the gluteus maximus, the upper segment of the iliotibial band, the anterior border of the tensor fasciae latae, and then extends longitudinally along the rectus femoris to the inside of the trouser leg above the knee.

[0031] It should be noted that the biceps femoris chain support band closely fits the main adduction muscle group on the posterolateral aspect of the thigh, providing dynamic support and posture guidance for the hip flexion, knee flexion, and leg clamping preparation and repositioning processes in the breaststroke.

[0032] It should be noted that the rectus femoris chain support band closely fits the entire knee extension dynamic path from hip stabilization and rectus femoris extension to knee joint control during the breaststroke, providing continuous muscle support and tension guidance for the breaststroke kicking phase.

[0033] In a preferred embodiment, the biceps femoris chain support band includes a first biceps femoris chain support band 1 and a second biceps femoris chain support band 2 that are symmetrically arranged on both sides. The first biceps femoris chain support band 1 and the second biceps femoris chain support band 2 pass through the following six key points or key areas in sequence: A1-anterior superior iliac spine; B1-tensor fasciae latae; C1-middle and lower segment of iliotibial band; D1-middle segment of biceps femoris belly; E1-junction area of ​​biceps femoris tendon-muscle belly; F1-upper edge of lateral popliteal fossa.

[0034] For example, A1: the anterior superior iliac spine (as an anatomical landmark above the iliac bone) is the attachment point of the sartorius muscle and part of the hip flexor muscle group, constituting the tension source of the tension band system in this invention.

[0035] For example, B1: the tensor fasciae latae located on the anterolateral aspect of the hip, forms a key turning point connecting the medial force chain and the lateral stabilization system.

[0036] For example, C1: the middle and lower segment of the iliotibial band located in the middle of the lateral thigh, close to the upper edge of the lateral femoral condyle, forms a key platform for guiding tension posterolaterally.

[0037] For example, D1: the middle section of the biceps femoris muscle located in the central region of the back of the thigh, which constitutes the main muscle group for the knee flexion movement in breaststroke.

[0038] For example, E1: the area at the junction of the biceps femoris tendon and muscle belly at the distal end of the biceps femoris muscle, which is close to the lateral aspect of the knee.

[0039] For example, F1: located on the posterolateral side of the thigh, at the upper edge of the popliteal fossa in the depression area above the knee joint, constitutes the termination anchor point of the tension band within the structurally permissible range.

[0040] It should be noted that the key points or key areas within the biceps femoris chain support band work together synergistically to provide targeted additional support for the biceps femoris, effectively improving muscle contraction efficiency during the breaststroke cycle and positively impacting muscle support, energy conversion efficiency, and athletic performance. The functions of each segment are as follows: A1B1 segment (A1-B1): During the initiation phase of the leg recovery in breaststroke, it provides hip flexion traction for the leg recovery chain, guiding the thigh to contract inward and backward, guiding the tension transmission from the inner muscle group to the outer side, forming an "oblique compression" of the leg recovery trajectory, and maintaining axial symmetry.

[0041] Segment B1C1 (B1-C1): Provides circumferential control force to the outer thigh, limiting ineffective movements such as outward rotation and backward sliding of the thigh before leg clamping.

[0042] C1D1 segment (C1-D1): Supports the mid-thigh retraction phase, providing longitudinal traction feedback for the knee flexion process and improving the efficiency of muscle synergy.

[0043] Section D1E1 (D1-E1): The preparatory stage for squeezing water and generating force, stabilizing the lateral knee structure and improving the accuracy and consistency of the leg-squeezing movement.

[0044] E1F1 segment (E1-F1): After the leg clamp is completed, assist the retraction of the outer structures above the knee, maintain the leg fit and movement rhythm, and prepare for leg extension.

[0045] In a preferred embodiment, the rectus femoris chain support band includes a first rectus femoris chain support band 3 and a second rectus femoris chain support band 4, which are symmetrically arranged on both sides. The first rectus femoris chain support band 3 and the second rectus femoris chain support band 4 pass through the following seven key points or key areas in sequence: A2 - the sacrospinalis muscle in the midline region of the lower back; B2 - the middle section of the upper edge of the gluteus maximus; C2 - the upper section of the iliotibial tract; D2 - the anterior edge of the tensor fasciae latae; E2 - the proximal end of the rectus femoris; F2 - the middle section of the rectus femoris belly; G2 - the area above the knee, on the inner side of the patella, above the trouser leg.

[0046] For example, A2: the sacrospinalis muscle in the midline region of the lower back, which is close to the junction of the lumbar vertebrae and the sacrum, and forms the anchoring origin of the posterior tension system.

[0047] For example, B2: the middle section of the upper edge of the gluteus maximus (the midline region of the upper part of the gluteus maximus), which constitutes the initial point of force generation for the hip extension chain.

[0048] For example, C2: located on the upper part of the outer thigh, near the hip acromion, the upper segment of the iliotibial band connects the outer edge of the ilium to the lateral thigh fascia, and its function is to stabilize the hip.

[0049] For example, D2: the anterior border of the tensor fasciae latae, which is located on the anterolateral aspect of the hip and serves as the transitional junction between the iliotibial band and the extensor muscles of the thigh.

[0050] For example, E2: the proximal end of the rectus femoris (lower border of the anterior inferior iliac spine), which is the attachment point of the rectus femoris and constitutes the upper force source that controls the linkage between hip flexion and knee extension.

[0051] For example, F2: the middle section of the rectus femoris belly, which corresponds to the thickest part of the anterior thigh muscle belly and constitutes the area where the rectus femoris exerts its most concentrated force.

[0052] For example, G2: the area above the knee, on the inner side of the patella above the trouser leg opening, which is the distal end of the rectus femoris muscle and the point where the trajectory of the final extension of the knee converges.

[0053] It should be noted that the key points or key areas within the rectus femoris chain support band cooperate and synergistically to provide targeted additional support for the rectus femoris, effectively improving muscle contraction efficiency during the breaststroke cycle and positively impacting muscle support, energy conversion efficiency, and athletic performance. The functions of each segment are as follows: Segment A2B2 (A2-B2): Provides posterior chain support during the preparatory phase of the breaststroke leg kick, keeping the pelvis stable during the kick and preventing lumbar collapse or hip eversion, thus providing a continuous tension origin for the rectus femoris chain.

[0054] B2C2 segment (B2-C2): Guides the tension from the buttocks to the outer thigh, stabilizes the abduction angle of the hip joint at the start of the push-off, limits the outward swing of the leg, and improves the symmetry of hip-knee coordinated force generation.

[0055] C2D2 segment (C2-D2): Limits the tendency of external rotation of the thigh during the mid-stance of the leg drive, generates a lateral contraction force at the tensor fasciae latae, and helps to keep the force trajectory near the trunk midline.

[0056] D2E2 segment (D2-E2): Guides the directional contraction of the rectus femoris muscle in the early stage of the push-off, improving the efficiency of hip flexion-knee extension transition.

[0057] E2F2 segment (E2-F2): Provides longitudinal traction and compression during the strongest phase of the push-off, strengthens the concentration of rectus femoris contraction, and improves the response of knee extension force.

[0058] F2G2 segment (F2-G2): Stabilizes the knee movement at the end of the breaststroke leg kick, provides symmetrical traction to the knee joint, makes the leg clamping more concentrated and effective, and completes the traction loop of the entire tension path.

[0059] For example, each tension band in this invention is a continuous, integral structure without any structural breaks.

[0060] For example, the tension band of the present invention is made of a composite structural material with high longitudinal elasticity and limited lateral extension. Longitudinal refers to the direction along the length of the tension band itself, and lateral is perpendicular to longitudinal.

[0061] For example, the tension band of the present invention is selected from nylon knitted hot melt adhesive tape with good elasticity and adhesion properties. Its structure is a multi-layer composite material, specifically including: a base material: nylon knitted fabric or nylon / polyurethane knitted fabric, providing overall elasticity and structural support; an intermediate adhesive layer: a non-thermoplastic cross-linked polyurethane base adhesive layer, used to enhance bonding strength and durability; and a surface adhesive layer: a polyurethane-based hot melt adhesive film layer, used to achieve hot-pressing lamination and positioning bonding with other fabrics.

[0062] For example, the elastic modulus of the tension band in this invention is 0.2 N / mm. 2 ~0.25N / mm 2 (e.g., 0.21 N / mm) 2 0.22N / mm 2 0.23 N / mm 2 0.24 N / mm 2 ).

[0063] Preferably, the width of the tension band described in this invention is 15~20mm (e.g., 16mm, 17mm, 18mm, 19mm).

[0064] It is understood that the combination of the tension band and the stretch fabric can be achieved using existing processes, such as hot pressing.

[0065] This invention uses pressure cloud maps under the breaststroke posture to guide the design location of localized pressurization areas, and combines research on the characteristics of the breaststroke posture and human anatomy to further propose the following specific design schemes for localized pressurization areas: Specifically, the local pressure area adopts a multi-layered fabric structure with low elongation along the body length direction, covering at least the perineal area, hip, buttocks and hind leg muscle groups, as well as the vastus lateralis muscles that are symmetrically distributed on both sides.

[0066] Specifically, the local pressure area includes a first pressure enhancement area 5 covering the perineal area, a second pressure enhancement area 6 covering the hip, buttocks and hamstring muscles, and a third pressure enhancement area 7 and a fourth pressure enhancement area 8 symmetrically distributed on both sides covering the vastus lateralis muscle.

[0067] Specifically, the multi-layered fabric of the localized pressure area is achieved by seamlessly bonding one or more new fabrics to the reverse side of the swim trunks. The new fabric can be the same as or different from the original fabric of that area. After seamless bonding, the localized pressure area has at least two layers of fabric. For example, the localized pressure area uses a double-layered fabric; specifically, a new fabric, i.e., the inner layer fabric, is seamlessly bonded to the reverse side of the swim trunks in the localized pressure area.

[0068] For example, the inner layer fabric is made of a material with a relatively high elastic modulus, applying a certain amount of pressure to the core area to help the body maintain a more streamlined shape. Preferably, the elastic modulus of the inner layer fabric is 0.27 N / mm². 2 ~0.32N / mm 2 (e.g., 0.28 N / mm) 2 0.29 N / mm 2 0.30 N / mm 2 0.31 N / mm 2 ).

[0069] For example, the elastic modulus of the stretch fabric described in this invention is 0.21 N / mm. 2 ~0.26N / mm 2 (e.g., 0.22 N / mm) 2 0.23 N / mm 2 0.24 N / mm 2 0.25N / mm 2 ).

[0070] For example, the size of the inner fabric is smaller than the area of ​​the target area (i.e., the local pressure area) it covers; preferably, the size of the inner fabric is 95% to 98% of the area of ​​the target area it covers. During the processing stage, the inner fabric is stretched to match the actual size of the target area it covers, so that when it is fitted to the body, it will produce a local pressure effect on the core target area.

[0071] In some preferred embodiments, the elastic modulus of the swim trunks in the locally pressurized area is 1.2-1.3 times the elastic modulus of the stretch fabric itself.

[0072] It is understandable that during swimming, the interaction between the human body surface and water generates pressure drag, which is one of the main factors affecting swimming speed. Properly selecting pressurized areas for structural design can optimize body contours, reduce cross-sectional area, and make the body lines more streamlined, thereby effectively reducing pressure drag.

[0073] This invention identifies key areas of pressure drag on the surface of swimming trunks by analyzing pressure cloud maps during the breaststroke, and precisely locates the areas requiring pressurization by combining this with the anatomical features of the breaststroke. By implementing localized pressurization in these key areas and optimizing the modulus relationship between the pressurized zone and the surrounding area, the pressure difference between the high-pressure zone and the adjacent low-pressure zone can be significantly reduced, resulting in a smoother pressure transition and effectively improving drag reduction.

[0074] In some preferred embodiments, the outer fabric of the swim trunks in the first pressure-reinforcing region 5 and / or the second pressure-reinforcing region 6 is a textured fabric, the design position of which is determined based on a surface shear stress diagram; the textured fabric is a warp-knitted fabric with a vertical stripe structure formed by a jacquard process.

[0075] For example, the periodic interval of the vertical stripes is 6-10mm (e.g., 7mm, 8mm, 9mm), preferably 8mm.

[0076] For example, the width of the vertical stripes is 1-2.5mm (e.g., 1.5mm, 2.0mm).

[0077] For example, the thickness variation of the vertical stripes does not exceed 40%-60% of the maximum thickness of the textured fabric. The thickness variation of the vertical stripes can be understood as the maximum thickness T of the vertical stripes. max T with minimum thickness min The difference.

[0078] For example, the maximum thickness of the textured fabric does not exceed 0.5-1.0 mm. The maximum thickness refers to the overall thickness of the textured fabric (including the thickness of the vertical stripes).

[0079] Specifically, the seam includes: The seams are symmetrically placed on both sides in the groin area; The seams, which are symmetrically arranged on the left and right sides and intersect with the thigh root area, extend longitudinally downward along the inner thigh and end at the lower edge of the trouser hem. A vertical seam is placed in the middle of the buttocks; And a seam located at the waistband, parallel to the upper edge of the waistband and encircling it.

[0080] Understandably, due to the large range of motion in swimming, the athletic physique of the swimmers, and the fact that swimsuits significantly impact drag, most swimsuits are designed with a three-dimensional structure to ensure a proper fit, conform to ergonomic principles, and not interfere with the swimmer's movements. Therefore, swimsuits still employ seam designs. Seams typically cause changes in fluid flow at the seams, easily leading to fluid separation and the formation of turbulent areas, thus increasing drag. Especially around the seams, the fluid velocity and direction change considerably, easily creating eddies and causing localized flow instability, further increasing drag. A well-designed seam can reduce the increase in drag caused by seams, thereby minimizing their impact. This invention guides the design area and direction of the swimsuit seams based on the surface streamline diagram of the breaststroke movement, and combines research on the characteristics of the breaststroke movement and human anatomy. Based on the swimsuit's pattern design and its seam design area and direction, the seam design of the swimsuit is optimized to minimize the increase in drag caused by seams.

[0081] For example, the symmetrical seams located in the groin region include: a first seam 9 and a second seam 10 that run obliquely downward from the anterior superior iliac spine (an anatomical landmark above the iliac bone) to the perineal region.

[0082] For example, the symmetrically arranged seams that intersect with the inner thigh region below the lowest point of the crotch and extend longitudinally downwards along the inner thigh, ending at the lower edge of the trouser hem, include: a third seam 11 and a fourth seam 12 that start from the inner side of the hip, near the perineum, extend longitudinally downwards along the inner thigh, and end at the inner side of the knee or the inner side above the knee. Preferably, they intersect 30-50 mm (e.g., 40 mm) below the lowest point of the crotch.

[0083] For example, the seam provided at the waist head and parallel to the upper edge of the waist head is: the fifth seam 13 provided at the waist head, 30-40mm away from the upper edge of the waist head and parallel to the uppermost edge of the waist head.

[0084] For example, the second pressure-enhancing region 6 covers the hip, buttocks and hamstring muscles, and its boundaries reach the first biceps femoris chain support band 1, the second biceps femoris chain support band 2 and the third seam 11 and the fourth seam 12.

[0085] For example, the first pressure-enhancing region 5 covers the perineal region and its boundary reaches the first joint 9 and the second joint 10, which are symmetrically positioned on both sides.

[0086] For example, the third pressure enhancement region 7 and the fourth pressure enhancement region 8 are pressure enhancement regions that are symmetrically distributed on the left and right sides and cover the location of the vastus lateralis muscle, and their boundaries reach the first biceps femoris chain support band 1, the second biceps femoris chain support band 2, the first rectus femoris chain support band 3, and the second rectus femoris chain support band 4.

[0087] For example, the seam is formed by an adhesive tape; for instance, the adhesive tape uses a thermoplastic elastomer film as the adhesive material, and the adhesive tape achieves a seamless bond between the fabrics under heating and pressure conditions.

[0088] Preferably, the thickness of the thermoplastic elastomer film of the present invention is 0.05~0.2mm, such as 0.08mm, 0.1mm, 0.12mm, 0.15mm, or 0.18mm. The thermoplastic elastomer film satisfies at least one of the following conditions: The melt index (MI, 175℃ / 2.16kg) is 10~20 g / 10min, preferably 15~16 g / 10min; The softening point is 70~90℃, preferably 75~85℃; The rheological temperature is 155~175℃, preferably 160~170℃; The tensile force at 40% strain (e.g., for a 25.4mm wide sample) is above 4.0N, such as 4.0~5.0N; The tensile force at 100% strain (e.g., for a 25.4 mm wide sample) is above 4.5 N, such as 4.5~5.5 N; It can withstand washing at 60℃ without delamination.

[0089] It is understood that "left-right symmetry" in this invention refers to mirror symmetry about the human body's central axis. "Same side" is understood as being located to the left or right of the human body's central axis. The human body's central axis refers to the intersection of the midsagittal plane, which divides the human body into two symmetrical halves along its long axis, and the human body.

[0090] Specifically, the design location of the tension band is determined based on pressure contour maps and sports biomechanics, including: The pressure design area of ​​the swim trunks is obtained based on the pressure cloud map; Based on the swim trunks' design, the pressure design area, and biomechanics, tension bands are set in the area where the swim trunks' design and the pressure design area overlap, and along the muscle force path or myofascial meridian (such as the force path of the rectus femoris and biceps femoris in the breaststroke leg kick).

[0091] It should be noted that the tension band designed based on the above determination method is conducive to further streamlining the body lines and improving the coordinated control of human muscles, enhancing the support of the swim trunks for the force-generating muscle groups, thereby further reducing pressure resistance and improving the stability of the swimming posture and the efficiency of power transmission.

[0092] Specifically, the design location of the localized pressurization zone is determined based on the pressure cloud map, including: The pressure design area of ​​the swim trunks is obtained based on the pressure cloud map; Based on the swim trunks' design and its pressure-reinforcing area, the local pressure-reinforcing area is set in the area where the swim trunks' design and pressure-reinforcing area overlap.

[0093] For example, obtaining the pressure design area of ​​the swim trunks based on the pressure cloud map includes: identifying the high-pressure area and the low-pressure area in the pressure cloud map, and taking the low-pressure area connected to the high-pressure area as the pressure design area of ​​the swimsuit.

[0094] For example, the high-pressure region and the low-pressure region in the pressure cloud map are identified by the following method: a high-pressure threshold and a low-pressure threshold are set, and the color corresponding to the pressure value in the pressure cloud map that is greater than or equal to the high-pressure threshold is obtained according to the high-pressure threshold as the high-pressure color, and the color corresponding to the pressure value in the pressure cloud map that is less than or equal to the low-pressure threshold is obtained according to the low-pressure threshold as the low-pressure color, and the region corresponding to the high-pressure color is obtained as the high-pressure region, and the region corresponding to the low-pressure color is obtained as the low-pressure region.

[0095] It should be noted that during swimming, the human body interacts with the water. The surface facing the water experiences positive pressure, while the rear of the body experiences negative pressure, creating high-pressure and low-pressure areas on the body surface. The pressure difference between these areas results in pressure drag, which is the main factor increasing resistance. Therefore, by accurately identifying high-pressure and low-pressure areas through pressure cloud mapping, and designating the low-pressure areas connected to the high-pressure areas as the localized pressurization areas of the swim trunks in this embodiment of the invention, the areas causing pressure drag are designated as the localized pressurization areas of the swim trunks in this embodiment of the invention, thus providing a basis for effectively reducing pressure drag. For the swim trunks in this invention, only the pressure distribution of the lower body needs to be considered in the pressure cloud map.

[0096] In some embodiments, a high-elasticity modulus fabric is selected for the localized pressurized area, or one or more new fabrics are seamlessly bonded to the localized pressurized area, or both a high-elasticity modulus fabric and one or more new fabrics are seamlessly bonded to the localized pressurized area.

[0097] It should be noted that the elastic modulus of a fabric refers to how easily the fabric resists deformation. The higher the elastic modulus, the less deformation the fabric will produce when subjected to force, and swimsuits made from such fabric will exert greater pressure on the human body.

[0098] Specifically, the relationship between the pressure of the swimsuit and the elastic modulus of the fabric is as follows: P=β+α×e, where P represents the pressure of the swimsuit, β represents a constant, α represents a regression coefficient, and e represents the elastic modulus of the fabric.

[0099] Preferably, β=1.162 and α=5.156.

[0100] It should be noted that the above relationship was obtained through experiments and regression analysis. Subjects wore single-layer swimsuits of the same size and structure made of several different fabrics. The pressure of the swimsuits at several typical locations was measured using an AMI3037-10 airbag pressure tester. The above relationship was obtained through regression analysis based on the measured pressure.

[0101] Specifically, the design location of the textured fabric is determined based on the surface shear stress diagram, including: Identify high shear stress regions in the surface shear stress map where the shear stress value is greater than or equal to the high shear stress threshold, and low shear stress regions where the shear stress value is less than or equal to the low shear stress threshold; The region where the shear stress value changes significantly or decreases sharply between the high shear stress region and the low shear stress region is defined as the flow separation region. Based on the design of the swim trunks and their flow separation areas, textured fabrics are used in the areas where the swim trunks' design and flow separation areas overlap.

[0102] Shear stress, as we understand it, refers to the tangential stress generated on the surface of the human body due to the viscosity of the fluid as it flows over it. It is used to measure the magnitude of the frictional force generated between the fluid and the human body surface due to relative motion.

[0103] Flow separation, as we understand it, refers to the phenomenon where fluid, when flowing over a human body surface, cannot maintain a smooth flow along the surface and begins to separate from it. As fluid flows over a human body surface, under the influence of the adverse pressure gradient and surface friction, the fluid velocity gradually decreases to zero. When the fluid velocity reaches zero, it indicates that backflow occurs. In the backflow zone formed by flow separation, the fluid flows in the opposite direction to the mainstream, making the fluid motion turbulent and significantly increasing fluid resistance. Sudden changes in shear stress are a significant cause of flow separation. For example, when a fluid transitions from a high-shear stress region to a low-shear stress region, the momentum exchange efficiency decreases sharply, easily triggering flow separation. Therefore, accurately identifying flow separation regions through surface shear stress mapping provides a foundation for effectively reducing fluid resistance.

[0104] It should be noted that the textured fabric surface has a distinct microstructure. If the curvature of the human body surface is too large, the adverse pressure gradient experienced by the fluid after passing through the point of maximum velocity will be greater, making flow separation more likely. Therefore, by adding microstructures to textured fabrics, in the transition region between high and low shear stress areas, the perturbation effect of the microstructures can reintroduce some momentum into the boundary layer before the fluid stalls, causing the flow to transition to turbulence earlier. In turbulent flow, the fluid's energy exchange and mixing capabilities are stronger, better resisting the influence of the adverse pressure gradient and suppressing the formation of flow separation zones, thereby effectively reducing fluid resistance.

[0105] It should be noted that textured fabrics, due to their microstructure, have greater frictional resistance than plain-weave fabrics. Using textured fabric throughout the swim trunks may not effectively reduce drag and could even have the opposite effect. Therefore, carefully selecting which areas of the swim trunks to use textured fabric is crucial. This invention identifies flow separation areas using surface shear stress mapping and, combined with the swim trunk's design and considering the characteristics of breaststroke movement, uses textured fabric only in areas where flow separation occurs, thereby suppressing flow separation and effectively reducing drag.

[0106] Specifically, the design area and design direction of the joint are determined based on the surface streamline diagram, including: (1) Identify the local vortex regions and local stable flow velocity regions in the surface streamline diagram; (2) The complement of the local vortex region is taken as the first region, and the intersection of the first region and the local flow velocity stable region is taken as the design region of the joint; (3) Identify the direction of the streamline of the surface streamline diagram in the seam design area of ​​the swim trunks, and take the direction of the streamline as the seam design direction of the swim trunks.

[0107] Specifically, local vortex regions in the surface streamline diagram are identified by the following methods: if the streamlines are circular, annular, spiral, or rotating in a certain local area, then the local area is a vortex region; or, if multiple arrows intersect in a certain local area and the arrows have a turning direction, then the local area is also a vortex region.

[0108] It's important to note that eddies cause streamlines in surface streamline diagrams to appear circular, annular, spiral, or rotating, rather than straight or unidirectional. Therefore, areas exhibiting these streamline shapes are identified as vortex regions. The arrows on the streamlines in a surface streamline diagram indicate the direction of flow velocity. When multiple arrows converge in a region and the arrows have a turning direction, it indicates a sudden change in flow velocity or a rapid change in flow direction, thus identifying it as a vortex region. Vortex regions typically lead to uneven changes in flow velocity, forming localized eddies. Seams, as abrupt structural changes on the swimsuit surface, act as "obstacles" to fluid flow, causing changes in fluid flow at the seams, especially in vortex regions. Changes in eddies and streamlines can lead to localized flow instability, resulting in increased drag. Therefore, swimsuit seam designs should avoid being placed in localized vortex regions. Since most swimsuits are sleeveless, backless, and knee-length, when identifying localized vortex regions, depending on the swimsuit's design, it's unnecessary to focus on areas not covered by the swimsuit, such as the head, shoulders, arms, and calves.

[0109] Specifically, the local flow velocity plateau region in the surface streamline diagram is identified by the following method: if the streamlines are of uniform and moderate density and relatively straight in a certain local area, then the local area is a local flow velocity plateau region.

[0110] It's important to note that streamline density reflects fluid velocity. Areas with high streamline density (dense streamlines) indicate higher flow velocities, while areas with low streamline density (sparse streamlines) indicate lower flow velocities. Areas with uniform streamline density indicate relatively stable flow velocities. Areas with relatively straight streamlines indicate minimal directional changes in fluid flow. Therefore, the seams of swimsuits should be designed to be located in areas of stable local flow velocity. This avoids unnecessary flow disturbances in areas of excessively high velocity and prevents compromises to swimsuit comfort in areas of excessively low velocity.

[0111] Furthermore, the streamlines of the surface streamline diagram are identified in the seam design area of ​​the swimsuit along the direction of the arrow, i.e. the direction of fluid flow, so that the seam design direction of the swim trunks is consistent with the direction of the streamlines.

[0112] It's important to note that the directionality of streamlines reflects the path and velocity direction of fluid flow. If the direction of the seam line differs significantly from the streamline direction, the fluid will encounter sudden obstacles or unnatural turns, increasing fluid disturbance and leading to localized velocity changes, flow separation, or vortex formation, thus increasing drag. Designing the seam line in the same direction as the streamlines allows for a smooth transition along the seam, maintaining stable flow. Therefore, the seam line design direction should follow the direction of the streamlines in the surface streamline diagram, i.e., the natural path of fluid flow, to minimize the impact of the seam line on fluid flow.

[0113] In one embodiment, the determination of the surface streamline diagram, pressure contour diagram, and surface shear stress diagram includes the following steps: Steps for obtaining characteristic postures of breaststroke: Based on the analysis of the motion posture and dynamic drag of breaststroke, the characteristic postures of breaststroke are obtained; Steps for constructing a human model for breaststroke: Obtain a human model with the characteristic postures of breaststroke through human body scanning; The steps for simulation analysis of the flow field in breaststroke are as follows: Computational fluid dynamics simulation is performed on the human body model with the characteristic posture of breaststroke to obtain surface streamline diagram, pressure cloud diagram and surface shear stress diagram specifically for breaststroke.

[0114] Specifically, the steps for acquiring the characteristic posture of breaststroke include: Based on the body position, arm movements, leg movements, breathing, and complete coordination of movements in the breaststroke, the basic posture of the breaststroke is obtained; A dynamic drag equation was established, and the basic posture of the breaststroke was analyzed based on the dynamic drag equation to obtain the analysis results. Based on the analysis results, the postures that are consistent with the analysis results are selected from the basic postures of breaststroke as the characteristic postures of breaststroke.

[0115] Specifically, the basic posture of the breaststroke is obtained based on the body position, arm movements, leg movements, breathing, and complete coordination of the movements: (1) Body position Wave posture: The head leads the way to initiate the wave, followed by a streamlined glide, shoulder lift to inhale, leg tuck to build up power, and push off to propel forward; during the glide phase, the body is fully extended, the head is submerged in the water, and the hips are slightly higher than the shoulders; during the inhale phase, the shoulders are raised about 10-15 centimeters, and the head is quickly extended forward. (2) Arm movements Outward sweep: Rotate the palm outward, sweep the forearm outward to 1.5 times the shoulder width, and sweep outward and backward; Inward sweep: Bend your elbow, accelerate the inward sweep of your forearm towards your chest, and sweep it inward and backward. Extend your arms: Extend your arms forward with your hands together, push your shoulders forward, and let your hands, extended arms and elbows form a streamlined shape together; (3) Leg movements Leg retraction: Slowly bring your heels towards your buttocks, keeping your knees approximately shoulder-width apart and bending your knees; eversion: The foot rotates outward to a W shape, and the ankle joint everts; Push-and-squeeze: The hip, knee, and ankle joints extend in coordination, and the legs accelerate backward and squeeze inward in an arc, while the knee joints extend; Gliding: Keep your legs together and straight, maintaining a streamlined shape; (4) Breathing Inhale: As your arms move inward to your chest, lift your upper body and head while inhaling. Exhale: As you extend your arms forward, submerge your head in the water and exhale slowly and continuously through your nose; (5) Complete coordination of movements When stroking, press your chest down; when pulling your legs back, lift your hips up; when kicking, thrust your torso forward. Arm, leg, and breathing generally follow a 1-1-1 coordination pattern: both arms stroke once, kick once, and inhale once.

[0116] Furthermore, the expression for the dynamic resistance equation is: , in, Indicates dynamic resistance. Indicates frictional resistance. Indicates shape resistance, Indicates wave resistance. Indicates the viscosity coefficient. Represents the gradient of swimming speed. Represents the area of ​​fluid distribution. Indicates the drag coefficient. This indicates the density of water. This represents the cross-sectional area of ​​the human body facing water. Indicates swimming speed, Indicates the amplitude of the wave. Indicates the length of the wave. Indicates the angle between the direction of swimming and the wavefront. Indicates a unit of time.

[0117] Specifically, the resistance a person experiences while swimming forward in water is called dynamic resistance. Dynamic resistance includes: frictional resistance, form resistance (also known as pressure drag), and wave resistance. Frictional resistance refers to the resistance generated when water around a person flows along the contours of the body in the opposite direction of movement as the person swims forward. Form resistance refers to the pressure difference created by the body pushing water forward, causing water layer movement and redistribution of pressure. In front of the person, the pressure on the water-blocking surface increases due to the pushing motion, creating positive pressure. Behind the person, the pressure tends to separate from the original water layer, creating negative pressure. Wave resistance refers to the resistance generated by the movement of water near the surface, causing water layer movement and pressure redistribution. The water layer moves along the person's movement path from high-pressure areas to low-pressure areas, creating waves.

[0118] It's important to note that wave drag is primarily related to body shape, swimming style, swimming speed, and water density, and is almost impossible to improve through swimsuit design. On one hand, the interaction between the body surface and water creates high-pressure and low-pressure areas. The pressure difference between these areas generates pressure drag (i.e., shape drag), which is the main factor increasing drag. On the other hand, seams can affect the boundary layer state and the location of flow separation points, further increasing pressure drag. Proper fabric placement, pressure band design, and seam design can effectively reduce shape drag. Therefore, analyzing the basic posture of each swimming style based on shape drag provides a foundation for improving swimsuit design.

[0119] Furthermore, the analysis results include: selecting the posture corresponding to a larger cross-sectional area of ​​the human body facing the water as the characteristic posture. As shown by the dynamic drag equation, form drag is proportional to the cross-sectional area of ​​the human body facing the water and the square of the swimming speed. For breaststroke, the human body faces forward, resulting in a relatively large cross-sectional area facing the water and thus greater drag. Therefore, the posture corresponding to a larger cross-sectional area of ​​the human body facing the water is selected as the characteristic posture.

[0120] It's important to note that form drag is proportional to the square of swimming speed—meaning it increases exponentially with speed. This implies that the increase in form drag is far greater than the increase in speed itself when swimming speed increases. Therefore, in high-speed competitive swimming, even a slight increase in speed can lead to a significant increase in form drag. If drag reduction measures can be implemented at high speeds to reduce the drag experienced by the swimmer, the same level of drag reduction at low speeds can result in a greater performance improvement, especially beneficial for competitive swimmers to achieve better results. The frontal cross-sectional area refers to the maximum cross-sectional area of ​​the swimmer in the direction of forward motion.

[0121] Specifically, the characteristic posture of the breaststroke is the kicking posture, which includes: the body position is horizontal, the arms are in an extended arm movement with the elbows bent at about 150°, and the legs are in a kicking movement with the knees bent at about 80°.

[0122] It should be noted that in the leg kick phase of breaststroke, the legs extend outwards, and the body is propelled out of the water by the balls of the feet. At this time, the body reaches its maximum cross-sectional area facing the water. Therefore, the leg kick is chosen as the characteristic posture, and the body position and arm movements are postures coordinated with the leg kick.

[0123] Specifically, the steps for constructing the breaststroke human model include: A scanning imager was used to scan the human body in the characteristic posture of the breaststroke; a human body model of the characteristic posture of the breaststroke was constructed based on the scanning results.

[0124] Preferably, a professional athlete is asked to assume the characteristic posture of the breaststroke, and the athlete is scanned using an F6 SMART handheld 3D scanning imager. The original scan result file is then input into the human body model construction module based on ECHO model processing software to obtain a human body model of the characteristic posture of the breaststroke.

[0125] Specifically, the simulation analysis steps for the frog-swimming flow field include: The computational domain is set according to the human body model; The computational domain and the human body model are meshed; By setting the calculation parameters, computational fluid dynamics simulation is performed on the meshed human body model within the computational domain to obtain the surface streamline diagram, pressure cloud diagram, and surface shear stress diagram of the human body model.

[0126] Specifically, setting the computational domain based on the human body model includes: setting the geometric model size of the computational domain, the distances from the human body model to the upstream, downstream, upper, lower, left, and right boundaries of the computational domain, and the entrance boundary conditions, exit boundary conditions, and wall boundary conditions of the computational domain; wherein, the computational domain is a cube, the geometric model size of the computational domain includes the length, width, and height of the computational domain, and the human body model is located inside the computational domain.

[0127] Preferably, the length, width, and height of the computational domain are set to 22.56m, 6.41m, and 6.32m, respectively; the distances from the human body model to the upstream, downstream, upper, lower, left, and right boundaries of the computational domain are set to 5m, 15m, 3m, 3m, 3m, and 3m, respectively. The inlet boundary condition of the fluid domain is set to a velocity inlet with a velocity of 1.5m / s and a flow Reynolds number Re of approximately 6.01×10⁵; the outlet boundary condition is set to a pressure outlet, ignoring shallow water pressure, and applying an ambient static pressure of 1 atmosphere at the outlet; the wall boundary conditions of the four surfaces of the fluid domain (upper, lower, left, and right) are all set to symmetric plane boundary conditions, and the fluid is water with a density of 998.2kg / m³.

[0128] It's important to note that Computational Fluid Dynamics (CFD) is a field that uses numerical simulation methods and computer technology to study fluid motion and interactions. CFD discretizes the fluid dynamics equations into a series of mathematical equations, then uses a computer to numerically solve them to simulate and analyze the fluid's motion, pressure, temperature, and other characteristics. The computational domain refers to the entire spatial region used to calculate fluid flow and related physical phenomena in a CFD simulation. The boundary of the computational domain defines the range of fluid flow and includes inlet boundary conditions, outlet boundary conditions, and wall boundary conditions. The fluid domain refers to the region within the computational domain that actually contains the fluid. Inlet boundary conditions are the physical conditions applied at the inlet of the fluid domain, outlet boundary conditions are the physical conditions applied at the outlet of the fluid domain, and wall boundary conditions are the physical conditions applied at the boundary where the fluid domain contacts the wall. The upstream boundary is the boundary where the fluid enters the computational domain in the direction of fluid flow; the downstream boundary is the boundary where the fluid exits the computational domain in the direction of fluid flow. The upstream boundary is usually set as the fluid inlet boundary condition, the downstream boundary is usually set as the fluid outlet boundary condition, and the left and right boundaries as well as the top and bottom boundaries are usually set as the fluid wall boundary conditions.

[0129] Specifically, the meshing of the computational domain and the human body model includes: Set the maximum and minimum size of the surface mesh; Set the type of volume mesh and its maximum and minimum sizes; Set the size of several locally encrypted influence bodies; Set the thickness of the first layer of the expansion layer mesh, the growth factor, and the number of expansion layers; The computational domain and the human body model are meshed according to the above settings.

[0130] Preferably, the computational domain and the human body model are meshed using the pre-processing software ANSYS Fluent Meshing. The maximum and minimum dimensions of the surface mesh are set to 200 mm and 1 mm, respectively; the volume mesh type is set to Poly-hexcore volume mesh, with maximum and minimum dimensions of 1000 mm and 1 mm, respectively; the dimensions of the three local refinement influence volumes are set to 10 mm, 20 mm, and 40 mm, respectively; the thickness of the first layer of the expansion layer mesh is set to 0.01 mm, the growth factor to 1.2, and the number of expansion layers to 15. Meshing the computational domain and each human body model according to the above settings yields approximately 20 million meshes for each human body model.

[0131] It should be noted that the localized mesh refinement effect is used to refine the mesh in a specific region without additionally dividing the computational domain, thereby improving the accuracy of the simulation. The expanded layer mesh is used to generate a high-resolution mesh near the wall boundary of the fluid domain to better capture the flow characteristics within the boundary layer. The thickness of the first layer of the expanded layer mesh refers to the thickness of the first layer of mesh cells generated near the wall boundary; the expansion factor of the expanded layer mesh refers to the ratio of the thicknesses of two adjacent layers of mesh cells in the expanded layer; and the number of expanded layers refers to the number of expanded layer mesh layers generated near the wall boundary.

[0132] Furthermore, the setting of calculation parameters and the performance of computational fluid dynamics simulation on the meshed human body model within the computational domain to obtain the surface streamline diagram, pressure contour diagram, and surface shear stress diagram of the human body model include: Select the solver and numerical solution method, and set the corresponding calculation parameters; Based on the solver and numerical solution method, the simulation results are obtained by performing computational fluid dynamics simulation on the meshed human body model in the computational domain using simulation software. Post-processing of the simulation results yields surface streamline diagrams, pressure cloud diagrams, and surface shear stress diagrams of the human body model.

[0133] Specifically, the selection of the solver and numerical solution method, and the setting of the corresponding calculation parameters, include: selecting a turbulence model solver based on the characteristics of the fluid surrounding a person swimming, wherein the SST k-ω turbulence model is used to close the Reynolds-averaged equations to obtain the governing equations; using the finite volume method to discretize the governing equations, wherein a second-order scheme is used to spatially discretize the spatial derivatives to reduce numerical discretization errors caused by mesh misalignment; selecting a pressure-velocity coupled solution method and using the SIMPLE algorithm to solve the problem to achieve better convergence performance; monitoring the total resistance and residual curve of the human body, while keeping the other settings at default.

[0134] It should be noted that the fluid surrounding a person while swimming is incompressible. The flow of the fluid around the person and swimming equipment is described by solving the Navier-Stokes (NS) equations. The Navier-Stokes (NS) equations include the continuity equation and the momentum equation. The expression for the continuity equation is shown below: Continuity equation: , in, For fluid density, This represents the Reynolds-mean velocity component with the mean sign omitted. Spatial coordinates; The expression for the momentum equation is shown below: , in, This refers to fluid pressure. , This represents the Reynolds-mean velocity component with the mean sign omitted. , For turbulent fluctuation velocity, These are the components of the Reynolds stress tensor. These are spatial coordinates.

[0135] Turbulence is an irregular flow phenomenon that occurs at high Reynolds numbers. Turbulence is often simulated numerically, with turbulence models serving as mathematical relationships for calculating Reynolds stress, forming a closed system of equations together with the Navier-Stokes equations. The standard Shear-Stress Transport (SST) k-ω turbulence model is the only turbulence model that truly captures vortices. The SST k-ω turbulence model is a two-equation hybrid model. It uses the Wilcox k-ω model in the near-wall boundary region and the k-ω model at the boundary layer edge and free shear layer, with a mixing function acting as a transition. It belongs to the two-equation eddy viscosity mode of incompressible / compressible turbulence integrated to the wall, thus providing a more accurate analysis of the flow field around the human body and the distribution of surface pressure. Therefore, the SST k-ω turbulence model is used to numerically calculate the flow field of human models corresponding to different swimming postures.

[0136] Specifically, based on the aforementioned solver and numerical solution method, the human body model after meshing is simulated in the computational domain in the simulation software. The simulation time step and total time are set as needed. During the simulation, the changes in the total resistance of the human body and the residual curve are monitored to ensure simulation convergence and obtain simulation results.

[0137] Specifically, the post-processing of the simulation results to obtain the surface streamline diagram, pressure cloud diagram, and surface shear stress diagram of the human body model includes: extracting velocity field data of the human body model surface from the simulation results, and generating the surface streamline diagram of the human body model based on the extracted velocity field data; extracting pressure data of the human body model surface from the simulation results, and generating the pressure cloud diagram of the human body model based on the extracted pressure data; and extracting wall shear stress data of the human body model surface from the simulation results, and generating the surface shear stress diagram of the human body model based on the extracted wall shear stress data.

[0138] It should be noted that surface streamline diagrams are visualization tools that use curves to show changes in fluid velocity and direction on the human body surface; these curves, called streamlines, are drawn along the tangent direction of the fluid velocity vector, and can intuitively show the dynamic behavior of fluid on the human body surface. Pressure cloud diagrams are visualization tools that use different colored areas to show the pressure distribution on the human body surface; the first color represents the highest pressure, the second color represents the lowest pressure, and several transition colors are set between the first and second colors. The first color, the second color, and the transition colors between the first and second colors are the colors corresponding to the pressure cloud diagram. The color of each area in the pressure cloud diagram can be represented by its corresponding color; the closer to the first color, the higher the pressure, and the closer to the second color, the lower the pressure, which can intuitively show the location of high-pressure and low-pressure areas on the human body surface. Similarly, a surface shear stress map is a visualization tool that uses different colors to show the distribution of shear stress on the human body surface. The third color represents the highest shear stress, the fourth color represents the lowest shear stress, and several transition colors are set between the third and fourth colors. The third color, the fourth color, and the transition colors between the third and fourth colors then correspond to the colors in the surface shear stress map. The color of each region in the surface shear stress map can be represented by its corresponding color; the closer to the third color, the higher the shear stress, and the closer to the fourth color, the lower the shear stress. This visually shows the location of high and low shear stress areas on the human body surface. The first and third colors can be the same color, and the second and fourth colors can also be the same color.

[0139] For example, if red is selected to represent the highest pressure and blue to represent the lowest pressure, and 18 transition colors are set between red and blue, then the color of each region in the pressure cloud map can be represented by the above 20 colors; the closer to red, the higher the pressure, and the closer to blue, the lower the pressure.

[0140] Understandably, this invention obtains a human body model with characteristic postures through human body scanning, and performs computational fluid dynamics simulation on the human body model to obtain surface streamline diagrams, pressure cloud diagrams, and surface shear stress diagrams, thereby improving the accuracy of numerical simulation analysis and providing a foundation for optimizing swimsuit design. This invention, through computational fluid dynamics simulation, reduces traditional experiments and tests, lowers costs, and improves efficiency.

[0141] It should be noted that, before designing the structure, the inventors, based on their research into the characteristics of the breaststroke posture and the anatomical structure of the human body, analyzed the activity mechanism of skeletal muscles during the breaststroke stroke cycle as follows: The upper limb movements in breaststroke can also be divided into a propulsion phase and a recovery phase. The propulsion phase begins with the shoulders and forearms extended, and the hands brought together above the head. The first half of the propulsion phase is similar to freestyle and butterfly, driven by the clavicular portion of the pectoralis major, with the latissimus dorsi quickly assisting. In the second half, the powerful contraction of the pectoralis major and latissimus dorsi pulls the hands and upper arms towards the midline of the body to complete the stroke. The force generated in the final phase propels the swimmer forward in the water and propels the upper body upward, the latter assisted by the paraspinal muscles. This action causes the swimmer's head and shoulders to break the surface. The flexion and rotation of the elbows bring the arms to the midline of the body, entering the recovery phase. During the recovery phase, to return the arms to the starting position, they need to pass under the chest, a process completed by the pectoralis major, anterior deltoid, and long head of the biceps brachii. These muscles work together to promote shoulder flexion, while the triceps brachii assists in elbow extension, completing the recovery phase. The leg kick in breaststroke is divided into a propulsion phase and a recovery phase. The propulsion phase can be further divided into an outward sweep and an inward sweep. At the start of the propulsion phase, the feet are hip-width apart, with the knees and hips simultaneously flexed. The outward sweep begins with the feet rotating outward, coordinated by the hip, knee, and ankle joints. After the feet extend outward, the outward sweep is completed by the straightening of the hip and knee joints. The gluteal muscles and biceps femoris help extend the hip, while the rectus femoris and quadriceps femoris work to straighten the knee. During the transition from the outward sweep to the inward sweep, the knee and hip joints are not yet fully extended, so the corresponding muscle groups continue to work in the inward sweep phase until the knee and hip joints are fully extended. At the start of the inward sweep, the legs are separated, and the thrust is generated by the rapid adduction of the legs. In the recovery phase, the rectus femoris and iliopsoas muscles are responsible for hip flexion, and the biceps femoris is responsible for knee flexion. Figure 6 As shown, the gray area represents the location of the muscles that exert force during the breaststroke; the darker the color, the greater the contribution of that muscle during the movement.

[0142] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and comparative examples.

[0143] Example 1: This embodiment provides a swim trunk designed for the characteristics of breaststroke, made of stretch fabric, which covers at least part of the thighs and buttocks when worn by the human body, with the side closest to the skin as the reverse side; the swim trunk includes local pressure areas, tension bands, and seams; The tension band is fixedly installed on the reverse side of the swim trunks. The design position of the tension band is determined based on pressure cloud map and sports biomechanics. The tension band includes a biceps femoris chain support band and a rectus femoris chain support band. The localized pressurization area uses a double-layer fabric, and the design location of the localized pressurization area is determined based on the pressure cloud map; The design area and design direction of the joint are determined based on the surface streamline diagram.

[0144] The tension cloud map and surface streamline map in this embodiment are obtained through the steps in the specific implementation method, see [link to detailed implementation method]. Figures 8 to 11 .

[0145] Specifically, the design location of the tension band is determined based on pressure contour maps and sports biomechanics, including: (1) Based on the pressure cloud map ( Figure 8 and Figure 9 ) to obtain the pressure-adjustable design area of ​​the swim trunks; (2) Based on the design of the swim trunks, the pressure design area and sports biomechanics, the tension band is set in the area where the swim trunks design and the pressure design area overlap and on the path of human muscle force exertion or myofascial meridian. Among them, according to the pressure cloud map ( Figure 8 and Figure 9 The process of obtaining the pressure design area of ​​the swim trunks includes: identifying the high-pressure area and the low-pressure area in the pressure cloud map, and taking the low-pressure area connected to the high-pressure area as the pressure design area of ​​the swimsuit.

[0146] Specifically, the high-pressure and low-pressure regions in the pressure cloud map are identified by the following method: a high-pressure threshold and a low-pressure threshold are set. Based on the high-pressure threshold, the color corresponding to the pressure value in the pressure cloud map that is greater than or equal to the high-pressure threshold is used as the high-pressure color. Based on the low-pressure threshold, the color corresponding to the pressure value in the pressure cloud map that is less than or equal to the low-pressure threshold is used as the low-pressure color. The region corresponding to the high-pressure color is used as the high-pressure region (positive pressure), and the region corresponding to the low-pressure color is used as the low-pressure region (negative pressure).

[0147] Based on pressure cloud map ( Figure 8 and Figure 9The design of the tension bands is guided by the study of the characteristics of the breaststroke posture and the human anatomy. The characteristic posture of the breaststroke is the kicking posture, which includes: a horizontal body position, arms extended with elbows bent at approximately 150°, and legs kicking with knees bent at approximately 80°. This embodiment uses four tension bands: Figures 1-3 In this embodiment, the four tension bands are: two symmetrical biceps femoris chain support bands, namely the first biceps femoris chain support band 1 and the second biceps femoris chain support band 2; and two symmetrical rectus femoris chain support bands, namely the first rectus femoris chain support band 3 and the second rectus femoris chain support band 4. The first biceps femoris chain support band 1 and the second biceps femoris chain support band 2 pass through the following six key points or key areas in sequence: A1-anterior superior iliac spine; B1-tensor fasciae latae; C1-... -Lower segment of the iliotibial band; D1-Middle segment of the biceps femoris belly; E1-Biceps femoris tendon-muscle belly junction area; F1-Upper border of the lateral popliteal fossa; The first rectus femoris chain support band 3 and the second rectus femoris chain support band 4 pass through the following seven key points or key areas in sequence: A2-Sacrospinalis muscle in the midline region of the lower back; B2-Middle segment of the upper border of the gluteus maximus; C2-Upper segment of the iliotibial band; D2-Anterior border of the tensor fasciae latae; E2-Proximal end of the rectus femoris; F2-Middle segment of the rectus femoris belly; G2-Upper border of the patella on the inner side of the trouser leg above the knee.

[0148] Specifically, the design location of the localized pressurization zone is determined based on the pressure cloud map, including: (1) Obtain the pressure design area of ​​the swim trunks based on the pressure cloud map; (2) Based on the design of the swim trunks and its pressure design area, the local pressure area is set in the area where the swim trunks' design and pressure design area overlap.

[0149] Based on the design location of localized pressurization areas guided by pressure cloud maps during the breaststroke, and combined with research on the characteristics of the breaststroke posture and human anatomy, the localized pressurization areas in this embodiment employ a double-layer fabric structure with low elongation along the body length direction. Figure 4 The local pressure areas are, in sequence: a first pressure enhancement area 5 covering the perineum, a second pressure enhancement area 6 covering the hip, buttocks and hamstring muscles, and a third pressure enhancement area 7 and a fourth pressure enhancement area 8 symmetrically distributed on both sides, covering the vastus lateralis muscles.

[0150] Specifically, the design area and design direction of the joint are determined based on the surface streamline diagram, including: (1) Identify the surface streamline diagram ( Figure 10 and Figure 11 The local vortex region and the local stable flow velocity region in the flow; (2) The complement of the local vortex region is taken as the first region, and the intersection of the first region and the local flow velocity stable region is taken as the design region of the joint; (3) Identify the direction of the streamline of the surface streamline diagram in the seam design area of ​​the swim trunks, and take the direction of the streamline as the seam design direction of the swim trunks.

[0151] Based on the design area and direction of the seams guided by the surface streamline diagram of the breaststroke posture, and combined with the study of the characteristics of the breaststroke posture and the human anatomical structure, this embodiment has a total of 6 seams, namely: The sutures are symmetrically located in the groin area: the first suture 9 and the second suture 10, which run obliquely downward from the anterior superior iliac spine (an anatomical landmark above and in front of the iliac bone) to the perineal area. The seams (first seam 9 and second seam 10) that are symmetrically arranged on the left and right sides and intersect with the thigh root area at 40 mm below the lowest point of the crotch and extend longitudinally downward along the inner thigh, ending at the lower edge of the pant leg: the seams that start from the inner side of the hip, close to the perineum area, extend longitudinally downward along the inner thigh, and end at the inner side of the knee or the inner side above the knee area, the third seam 11 and the fourth seam 12. The fifth seam 13 is located at the waist head, 30mm from the upper edge of the waist head, and is parallel to the uppermost edge of the waist head, encircling the waist head. The vertical seam located in the middle of the buttocks is the sixth seam 14.

[0152] The seam is formed by an adhesive tape, which is a thermoplastic elastomer film.

[0153] In this embodiment, the second pressure-enhancing region 6 covers the hip, buttocks, and hamstring muscles, and its boundaries extend to the first biceps femoris chain support band 1, the second biceps femoris chain support band 2, the third seam 11, and the fourth seam 12 (see...). Figures 1-5 (The light green area in the image). The first pressure-enhancing area 5 covers the perineal area, and its boundary reaches the first and second symmetrical seams 9 and 10. The third and fourth pressure-enhancing areas 7 and 8 are symmetrically distributed pressure-enhancing areas covering the vastus lateralis muscle, and their boundaries reach the first biceps femoris chain support band 1 and the second biceps femoris chain support band 2, as well as the first rectus femoris chain support band 3 and the second rectus femoris chain support band 4.

[0154] Example 2: The swim trunks provided in this embodiment are the same as those in Embodiment 1, except that: the outer layer fabric of the first pressure reinforcement area 5 and the second pressure reinforcement area 6 in this embodiment is a textured fabric; the textured fabric is a warp-knitted fabric with a vertical stripe structure formed by jacquard process; the periodic interval of the vertical stripes is 8mm; the width of the vertical stripes is 1.5mm; the thickness variation of the vertical stripes does not exceed 60% of the maximum thickness of the textured fabric; and the maximum thickness of the textured fabric is 1.0mm.

[0155] In the above embodiments, the stretch fabric used for the main body of the swim trunks is made of 72% nylon and 28% spandex, and is sourced from Maniafatture Italiane Scudieri SRL with the following basic parameters: thickness 0.3mm, elastic modulus 0.23N / mm². 2 123g / m 2 Both the warp and weft elasticity are 55%.

[0156] The tension band in the above embodiment is a nylon knitted hot melt adhesive tape, which was purchased from San Chemicals Ltd. and has the following basic parameters: thickness 0.8mm, width 20mm, elastic modulus 0.25N / mm². 2 Weight: 275g ± 5% per meter. The nylon knitted hot melt adhesive tape has a multi-layer composite structure, in which the base material is nylon knitted fabric, the middle adhesive layer is a non-thermoplastic cross-linked polyurethane base layer, and the surface adhesive layer is a polyurethane-based hot melt adhesive film layer.

[0157] The thermoplastic elastomer film in the above embodiments was purchased from SAN FANG CHEMICAL INDUSTRY CO.,LTD (e.g., brand name LSCHYS-WO31) and its basic parameters are as follows: thickness of 0.1 mm, melt index (MI, 175℃ / 2.16 kg) of 15.5 g / 10 min; softening point of 75~85℃; rheological temperature of 160~170℃; tensile force at 40% strain (e.g., 25.4 mm wide sample) of 4.0~5.0 N; tensile force at 100% strain (e.g., 25.4 mm wide sample) of 4.5~5.5 N; and can withstand washing at 60℃ without delamination.

[0158] In the above embodiment, the inner layer fabric of the locally pressurized area is 75% nylon and 25% spandex, purchased from Maniafatture Italiane Scudieri SRL, and its basic parameters are as follows: thickness 0.5mm, elastic modulus 0.3N / mm. 2 163g / m 2The warp elasticity is 60% and the weft elasticity is 70%; the inner fabric size is 98% of the target area to be covered, and it is stretched to the actual target area size during the processing and manufacturing stage.

[0159] Comparative Example The swim trunks in this comparative example have the same shape and size as those in Example 1, and the overall fabric and seam settings are the same as those in Example 1. However, this comparative example does not have tension bands or local pressure areas.

[0160] The performance of the swim trunks in the above embodiments and comparative examples was tested, and the specific steps are as follows: Three-dimensional scanning was used to collect data on the body shape and size of swimmers when they wore different swim trunks in the embodiment and the comparative example. The shaping effect of different swim trunks on key parts (hips and legs) was quantified, and the geometric index of "close to streamline" was used as an indirect characterization of resistance.

[0161] Compared to the comparative example, the swim trunks of this embodiment achieve a significant reduction in hip cross-sectional geometry: the upper hip circumference is reduced by 2.9%, the hip circumference by 0.9%, the thigh circumference by 3.2%, and the thigh circumference by 4.5%. These geometric changes indicate a more streamlined body shape, which, according to fluid dynamics principles, corresponds to a potential reduction in differential pressure drag.

[0162] To objectively evaluate the performance of the swim trunks, a randomized crossover experimental design was adopted: 8-12 professional breaststroke swimmers of the same level were selected and tested in a standard 50-meter pool (water temperature 26±1℃) wearing the swim trunks of the example and the comparative example, respectively. The testing process adopted a double-blind randomization principle and ensured sufficient test intervals to eliminate the interference of fatigue factors.

[0163] The experimental results show that, compared with the comparative example: When wearing the swim trunks described in this example, the athlete's body undulations in the water are more stable, and wave deformation is reduced; The swim trunks, as demonstrated, effectively guide the direction of force during the leg kick phase, resulting in a more focused and coordinated movement trajectory. Athletes generally reported that the swim trunks provided support for key muscle groups without affecting joint flexibility; Throughout the entire swimming process, the propulsion efficiency is improved when the swim trunks are worn, as demonstrated in this embodiment. Based on the results of all tests, the embodiment showed significant advantages in both turnaround speed and overall motion efficiency.

[0164] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. Swim trunks designed specifically for the characteristics of breaststroke, characterized in that, Made of stretch fabric, when worn by the human body, the stretch fabric covers at least part of the thighs and buttocks, with the side closest to the skin being the reverse side; The swim trunks include a localized pressure zone, tension bands, and seams; The tension band is fixedly installed on the reverse side of the swim trunks. The design position of the tension band is determined based on pressure cloud map and sports biomechanics. The tension band includes a biceps femoris chain support band and a rectus femoris chain support band. The biceps femoris chain support band starts from the anterior superior iliac spine, obliquely passes through the sartorius muscle, turns to the lateral posterolateral region of the thigh, passes successively through the tensor fasciae latae, the middle segment of the iliotibial band and the biceps femoris muscle, and finally terminates at the upper edge of the lateral popliteal fossa; the biceps femoris chain support band includes a first biceps femoris chain support band (1) and a second biceps femoris chain support band (2) that are symmetrical on both sides; the path of the biceps femoris chain support band closely follows the main adduction muscle group on the posterolateral side of the thigh, providing dynamic support and posture guidance for the hip flexion, knee flexion, leg clamping preparation and repositioning process in the breaststroke; The rectus femoris chain support band starts from the lower back, passes through the gluteus maximus, the upper segment of the iliotibial band, the anterior border of the tensor fasciae latae, and then extends longitudinally along the rectus femoris to the inner side of the trouser leg above the knee; the rectus femoris chain support band includes a first rectus femoris chain support band (3) and a second rectus femoris chain support band (4) that are symmetrical on both sides; the rectus femoris chain support band closely fits the entire knee extension dynamic path from hip stability, rectus femoris extension to knee joint control in the breaststroke movement, providing continuous muscle support and tension guidance for the breaststroke kicking phase; The local pressure area is made of multi-layered fabric, and the design position of the local pressure area is determined based on the pressure cloud map; the local pressure area includes a first pressure enhancement area (5) covering the perineum area, a second pressure enhancement area (6) covering the hip, buttock and hind leg muscle group, and a third pressure enhancement area (7) and a fourth pressure enhancement area (8) symmetrically distributed on the left and right sides covering the vastus lateralis muscle. The outer fabric of the swim trunks in the first pressure reinforcement area (5) and / or the second pressure reinforcement area (6) is a textured fabric, which is a warp-knitted fabric with a vertical stripe structure formed by jacquard process. The design area and design direction of the joint are determined based on the surface streamline diagram; the joint includes: The sutures are symmetrically arranged in the groin area of ​​the thigh, including the first suture (9) and the second suture (10) that run obliquely downward from the anterior superior iliac spine to the perineal area. The seams that are symmetrically arranged on the left and right sides, intersect with the seams of the root of the thigh below the lowest point of the crotch and extend longitudinally downward along the inner thigh to the lower edge of the leg opening, include the third seam (11) and the fourth seam (12) that start from the inner side of the hip, close to the perineum, extend longitudinally downward along the inner thigh, and end at the inner side of the knee or the inner side above the knee. A vertical seam is placed in the middle of the buttocks; And the seam located at the waistband, parallel to the upper edge of the waistband and encircling it; The first pressure-enhancing area (5) covers the perineal area and its boundary reaches the first joint (9) and the second joint (10) that are symmetrical on the left and right sides. The second pressure-enhancing area (6) covers the hip, buttocks and hamstring muscles, and its boundaries reach the first biceps femoris chain support band (1), the second biceps femoris chain support band (2) and the third seam (11) and the fourth seam (12). The third pressure enhancement area (7) and the fourth pressure enhancement area (8) are pressure enhancement areas that are symmetrically distributed on the left and right sides and cover the vastus lateralis muscle. Their boundaries reach the first biceps femoris chain support band (1), the second biceps femoris chain support band (2), the first rectus femoris chain support band (3), and the second rectus femoris chain support band (4).

2. The swim trunks according to claim 1, characterized in that, The first biceps femoris chain support band (1) and the second biceps femoris chain support band (2) pass through the following six key points or key areas in sequence: A1-anterior superior iliac spine; B1-tensor fasciae latae; C1-middle and lower segment of iliotibial band; D1-middle segment of biceps femoris belly; E1-junction area of ​​biceps femoris tendon-muscle belly; F1-upper edge of lateral popliteal fossa.

3. The swim trunks according to claim 1, characterized in that, The first rectus femoris chain support band (3) and the second rectus femoris chain support band (4) pass through the following seven key points or key areas in sequence: A2 - the sacrospinalis muscle in the midline region of the lower back; B2 - the middle section of the upper edge of the gluteus maximus; C2 - the upper section of the iliotibial tract; D2 - the anterior edge of the tensor fasciae latae; E2 - the proximal end of the rectus femoris; F2 - the middle section of the abdominal part of the rectus femoris; G2 - the area above the knee, on the inner side of the patella above the trouser leg opening.

4. The swim trunks according to claim 1, characterized in that, The design location of the textured fabric is determined based on the surface shear stress diagram.

5. The swim trunks according to claim 1, characterized in that, The periodic interval of the vertical stripes is 6-10 mm.

6. The swim trunks according to claim 1, characterized in that, The width of the vertical stripes is 1-2.5 mm.

7. The swim trunks according to claim 1, characterized in that, The thickness variation of the vertical stripes shall not exceed 40%-60% of the maximum thickness of the textured fabric.

8. The swim trunks according to claim 1, characterized in that, The maximum thickness of the textured fabric shall not exceed 0.5-1.0 mm.

Images