(Part - 2)
1. Jetconcept bodysuit by adidas Adidas was the first company to introduce a full bodysuit in competitive swimming in 1998. But the adidas innovation team wasn't satisfied, and began working on a new concept after the Sydney Olympics in 2000. Adidas, the leading sports brand, introduced a new swim suit called the adidas Jetconcept (Fig 1) on July 19, 2003 in Barcelona by adapting ad apting a technology already used by commercial aircraft. The idea the adidas innovation team came up with was unique: Instead of focusing on friction drag (caused by the surface of a swimmer) that only accounts for 8 per cent of the drag a swimmer faces in the water they looked into the effects of form drag (caused by the shape of a swimmer) that account for 56 per cent. Adapting a technology already used by commercial aircrafts they created the adidas Jetconcept. This full bodysuit shows a revolutionary approach by not only reducing the drag that the swimmer faces in the water but also influencing the way the water flows over the swimmer's body. Small "riblets" (Fig 3), integrated in the new suit, channel the water and thereby shift the turbulence that occurs on the swimmer's body and reduce the amount of water a swimmer carries on his back. Using specially developed riblets, adidas has created a bodysuit that behaves much like a commercial aircraft in flight. Ribbed panels, modelled after the grooves found on an airplane's fuselage and wings, extend from the underarm to the lower back and cover the gluteus maximum, helping channel water fluidly over back - reducing active drag and turbulences. The result is upto 3 per cent increase in swimming performance. 42
APPAREL VIEWS / NOVEMBER 2010
The adidas Jetconcept bodysuit transforms the hydrodynamic characteristics characteristics of the human anatomy from the moment of dive in, during the swim stroke, at the turn and during the underwater gliding phase.
1.1 How does the suit work? The inspiration for the Jetconcept bodysuit came from the V-shaped grooves currently used on the wings and fuselage of civil aircraft. The strong performance improvement in these aircrafts has been transferred to the idea of form drag and friction drag reduction during a swimmer's gliding phase. 1.1.1 The science behind man in water The Jetconcept suit is one that adidas has studied, researched, tested and devised over several years together with Ian Thorpe and other top class swimmers. Overall, tested swimmers believe that the new suit raises legs higher and changes the body position for better horizontal and flat propulsion. This "feeling" is scientifically documented and based on the speed of water moving under the body, and less water on the swimmer's back. This phenomenon is best explained through the science of hydrodynamics. 1.1.2 Hydro science and technology For swimmers, the challenge for increasing performance is based on the flow of the water over the body; adding riblets changes this water flow. To reduce an average of 70 kg of "dead water" that sit upon the swimmers back, riblets are placed in scientifically proven positions. With adidas Jetconcept riblets technology, drag is minimised, thereby increasing speed in the water. The adidas Jetconcept bodysuit provides athletes with the most beneficial tools to perform.
Fig 1. adidas Jetconcept
1.2 The Jetconcept bodysuit: Riblets Ribbed panels extending from the underarm to the lower back and covering the gluteus maxims help channel water over the swimmers back to reduce active drag, streamline movement and cut turbulence. The amount of water carried on the swimmer's back is reduced.
Fig 2. Ian Thorpe testing in the wind tunnel
Fig 4. Riblets advantage
2.1 A7 Technology The A7 is a hybrid design blending dual fabrics with one common purpose – speed and is most advanced Neoprene suit. The most advanced neoprene on the market combined with woven micro fibre control panels produce optimal results for dropping time. The suit teams both functionality and precision and never compromises movement.
Fig 3. Riblets on adidas Jetconcept
Lycra® power Lycra® power materials increase speed and endurance by using compression. This compression holds the body better in the water, stimulates skin receptors for a more accurate, efficient swim stroke and allows for faster recovery times due to increased blood circulation. Second skin fit The "Second skin fit" provides maximum flexibility and freedom of movement by preventing water from penetrating at the neck, wrists and ankles - reducing water retention. Flatlock seams Strategically placed flatlock seams reduce water drag and add comfort.
2 Tracer A7-TYR sport TYR Sport Inc. is Co-founded by an Olympic medallist and USA Swimming Co-Captain. TYR has been involved in full body technical suit research and development for the past three Olympiads. Beginning at the US Olympic Training Centre in 1999, full bodysuit tests concluded drag reduction was achieved by 6 per cent at the International Centre for Aquatic Research.
TYR has continued to improve upon its proprietary “zoned compression” model of performance suits. The A7 securely locks muscles in, providing precise compression where muscle fatigue can form during exertion, while also allowing range of movement throughout the torso, hips and knees with the BioMark III neoprene. The suit caters to a swimmer’s range of movement while addressing muscle oxygenation, and energy return.
2.2 Dual fabric 2.2.1 Outer surface Limestone based Micro-Honey Micro-Honeycomb comb structure creates hydrogen bonding on the surface forming a ball-bearing effect of water molecules. The slick hydrogen bonded surface allows for water molecules to roll over the suit at a drag co-efficient of only 0.021, a decrease of over 34 per cent from the existing Yamamoto SCS fabric used by others. 2.2.2 Middle layer The flexible Titanium alloy layer provides optimal thermoregulation which aids in the reduction of lactic acid in the blood, optimising muscle performance. Titanium is recognised for its high strength-to-weight ratio which allows the material to contour to the natural shape of each athlete, significantly reducing stress and fatigue on the muscles. 2.2.3 Base layer The single knit stretch polyester layer has a water absorption ratio of 0.5 per cent allowing the material to stay as light as possible.
TYR was the first company to de-compose the components of overall total drag in racing suits in 2004. Significant improvements in research technique with the University at Buffalo, State Universit y of New York, found an 18 per cent reduction in pressure drag, 53 per cent in wave drag and a 10 per cent overall reduction in drag.
Fig 7. 3 layer fabric structure – 3mm thickness
2.2.4 Woven blend At 60 per cent the weight of neoprene, but with 50 per cent greater memory return, the fabric provides all the control muscles need but reduces the weight of the suit by 25 per cent. This hydrophobic woven fabric is featured along the suit’s torso, legs, and back to allow necessary compression along the major muscle groups throughout the evolution of a swimmer’s stroke. Super-lightweight, quick drying, and chlorine-resistant, it is intricately stitched for maximised muscle oxygenation return through vibration control.
3. Speedo
Zoned compression, improved durability and uncompromised flexibility results in • 34 per cent drag reduction • +50 per cent memory return • 5 per cent water absorption
Fig 5. Tracer A7-TYR sport
Fig 6. Tracer A7-TYR sport
Speedo is a leading manufacturer of swimwear and accessories. The Speedo® LZR Racer™ is the world’s fastest swimsuit is made from a unique lightweight, water repellent and fast-drying fabric that has been developed after three years of research APPAREL VIEWS / NOVEMBER 2010
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Fig 8. Speedo® LZR Racer™
Fig 9. LZR Racer
Fig 11. LZR Racer: Fitting guide
with NASA to reduce drag and help hold the swimmer’s body in a more streamlined shape. Speedo says the suit has been independently tested as the "world's fastest,” a claim that translates to up to 5 per cent more efficiency for swimmers. The new suit has 10 per cent less passive drag (meaning the drag present when the swimmer is gliding through the water after a dive or turn) than Speedo’s 2004 Fastskin FSII and 5 per cent less passive drag than the Fastskin FS-Pro®. The specially engineered, highly flexible fabric called LZR Pulse™ is ultrasonically welded so as to appear seamless. It incorporates low drag "LZR" panels designed to create a corset-like effect that supports the swimmer in the optimum body position in the water and helps them hold it for longer. The LZR Racer’s unique design also provides swimmers with up to 5 per cent more efficiency in terms of their oxygen intake, enabling them to swim stronger for longer. Features of Speedo LZR Racer • It has panelled compression compression,, makes the body streamlined • Made up of only three panels! panels! Less panels>> Less seams>>Less drag • Fabric has sharkskin like like texture, hence excellent ent water repellency and very less drag • It got 10 per cent less drag than Fastskin Fastskin FSII and 5 per cent less drag than FS-Pro • 4 per cent faster faster in starts and turns • 5 per cent better oxygen oxygen efficiency efficiency
3.1 LZR Racer: An inside view 3.1.1 Fabric • The fabric used in LZR Racer is LZR Pulse, Pulse, which is basically made of Bond last yarns • Very light, 104 GSM only only • Constitutes 70 per cent Polyamide Polyamide micro fibres, 30 per cent Elastane • “Shark skin” like texture makes it water repellent, repellent, quick drying, and low drag • The fabric reduces muscle muscle oscillation oscillation and skin vibration through powerful compression 3.1.2 Knitting and other technology • Warp knitting of bond last yarn • Made of three panels panels only welded together together by ultrasonic welders • A panelled structure enables enables localised compression compression at specific muscles • The shark-skin appearance appearance is enabled by the knitting action 44
APPAREL VIEWS / NOVEMBER 2010
Fig 10. Built for speed
• Lappi Lapping ng movement movement Front guide bars 1 and 1 lap Back guide bar 3(4) and 1 lap in opposite direction 3.1.3 Threading • Front and back guide bars are fully threaded • Each of the three panels which make make up the suit is made-to-measure • The swimmers body is 3D-scanned and is analyzed by special software developed by Ansys Corp. • Finally the panels are made which which fit the swimmer swimmer precisely 3.1.4 Aerodynam Aerodynamics ics • Panels are laminated in in PU layers to create a Hydro Hydro Form Compression System to compress the body in a streamlined shape • Speedo tested the surface surface drag of more than 60 types of fabric to see which offered the ultra fast speed through lower skin friction drag • The wind tunnels of NASA gave the accurate fluid dynamic study of the swimmer enabling precise reduction in drag possible • Low profiles zips were used, used, which have been bonded with fabric, further reducing drag • Drag has been reduced by using using special water water repellent fabric
Fig 12. LZR Racer: Unique combination of fabric, design and construction
3.1.5 Seams • Seams are generally flat to reduce scraping • Ultrasonically welded, bonded seams create a perfectly smooth yet flexible streamlined surface • Seams direction direction matter in aerodynamics aerodynamics and hence they run lengthwise to reduce drag
(By Vasant R. Kothari, Assistant Professor, Department of Fashion Technology, NIFT, Bangalore, Neha Goyal & Megha Sheoran, MFTech, NIFT, Bangalore)
