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Bicycle shorts are form-fitting shorts designed specifically for the cyclist. A close inspection reveals that they differ significantly from typical jogging or beach shorts. Bicycle short material is usually a lightweight micro denier or close-knit woven fabric that protects against excessive moisture build-up during cycling. Upon removing a pair from its package and shaking it, you’ll notice that it retains its contoured form, the legs slightly bent to accommodate the cyclist’s position on a bicycle. Each leg extends to just above the knee and ends in an elasticized band that prevents the shorts from crawling up as the cyclist peddles. To better accommodate the contours of the lower body, the shorts are usually constructed of four, six, or eight separate panels that have been seamed together, and their streamlined design produces a slimming effect on waist, hips, and legs. The shorts also feature a padded lining stitched inside the crotch area to protect against saddle abrasion and other forms of irritating friction and to cushion against road bumps.
Photos of cyclists at the turn of the century show them wearing shorts, knickers, or simply pants with the legs rolled up (although women sometimes rode bicycles, only men rode competitively at that time). Early bicycle shorts were generally made of cotton or wool fabric. As the sport became more popular and more competitive, cyclists continually sought ways to improve their speed. All aspects of cycling were examined and improved, including not only the bicycle, protective headgear, and footwear, but the clothing as well. Cyclists discovered that hunching forward over the handlebars reduced wind resistance to their upper bodies and helped to
shave seconds off their time. However, baggy trousers that caught the wind negated the benefits of this streamlined position. Another problem related to loose-fitting shorts was that they formed irritating folds that chafed, causing saddle sores that could easily become infected from bacteria accumulating between sweat and clothing. Cyclists responded to these problems by utilizing new fabrics and designs. Wind tunnel tests have shown that smooth, shiny, satiny material affords the least resistance, while stretchy, tight-fitting fabric offers an additional advantage: it won’t bunch up in the groin area. Today, cyclists use synthetic fabrics designed with these characteristics, some of the most popular being Dupont’s Lycra, Coolmax, and Supplex. To reduce the problem of moisture buildup, cyclists today favor black bicycle shorts. Whereas sweat between the legs caused discoloration in early bicycle shorts, today even multicolored shorts typically feature black inner panels to combat discoloration.
To lessen chafing, cyclists experimented with a number of liner fabrics before settling on chamois. This soft cloth not only protected best against abrasion, it also provided wicking, meaning that it absorbed moisture from the skin, carrying it to the surface where air currents could dry it. Today’s liners are contoured to fit the groin area, and they extend from front to back, cut in a Y- or an hourglass shape. The chamois, usually synthetic, will have several layers: the layer that comes in direct contact with the skin will be a soft “ultrasuede” fabric; the next layer, a cotton terry cloth with wicking properties; the third layer, a foam or gel cushion, and the outermost layer, a close-knit fabric such as nylon or combination nylon/Lycra for extra protection against outside elements. Current versions of the chamois are also treated with an antibacte¬rial agent to prevent fungal infections (similar to athlete’s foot) in the groin area.
Today, there are two types of shorts: the more common bicycle short with an elastic waistband and a one-piece, bib type short without a waistband that is held up with suspender-type straps attached to a high Y- or U-shaped back panel. This short is mainly used by those who feel that the elastic waist on standard bicycle shorts hampers their breathing. Over the past decade, the tight-fitting or “skin” short has grown in popularity, and it can now be found in most major department and sports apparel specialty stores. Although these shorts are designed for cycling, many people wear them for comfort and exercise other than cycling.
Choosing fabrics for bicycle shorts entails considering several requirements, including the degree of waterproofing or water-resistance for wick-dry capabilities, drying time, breathability, and wind proofing.
Manufacturers tend to use synthetic fabrics such as spandex, a polyurethane fiber that returns to its original shape after stretching, although they are now blending these fabrics with natural fibers like cotton. Spandex is a stable fabric that retains its elasticity through dyeing, finishing, and frequent laundering.
The inner liner is called a chamois because it was originally made from the chamois, a goat like antelope found in Europe and the Caucasus Mountains. Today, the liner is usually made from synthetic chamois mechanically molded to match anatomical contours. The liner also contains a petroleum-based fiber such as polypropylene, which enhances its wicking capabilities. Most manufacturers have their own fabric labels with similar fabric properties and wicking capabilities. One manufacturer, Cannondale, has a patented Biosuede o chamois liner. Other trade names such as Ultrasuede and Supersuede have similar properties.
Cyclists choose their apparel carefully, particularly if they compete: a raised seam can prove very irritating after several hours of strenuous cycling. Designers thus strive to develop the optimal cycle wear. Designs range from the less expensive four-panel cut to the more expensive eight-panel cut. The more panels used, the better the contours of the final product will match the shape of legs, waist, and groin. To accommodate the bent- over rider, the panels are cut higher in back and lower in front. Designers also consider sizing needs, and today this means designing bicycle shorts for both men and women. For example, the female cyclist needs a bicycle short with a small, high waistline that has more fullness in the hips than a male cyclist’s bicycle short. The liner is also different for men and women, offering support and protection for the former, and a cotton/polyester blend for women. Designers first develop prototypes that are subjected to rigorous testing and revising before a bicycle short is approved for mass production.
The Manufacturing Process
Although more clothing manufacturers are making and distributing bicycle shorts for general sport and even nonathletic use, this section will describe how the short designed for the professional cyclist is manufactured.
1 First, the fabric (usually a blend of polyester, cotton, spandex, and nylon) must be manufactured. This involves spinning and combining the various threads into a single fabric, washing and drying the fabric, and then dyeing it. Next, it is saturated or sprayed with a water resistant finish before being cut into panels according to pattern specifications set by the designer. The various panels are then carefully sewn together. To avoid raised “ridges,” seams may be offset for a smoother finish. Finally, elastic is inserted in the waistband of the sewn short. Gripper elastic bands are also sewn into the cuffs at the short’s hem.
2 The chamois liner’s layers are cut out according to pattern specifications before being bonded or laminated together. After assembly, they are stitched along the outer edges to prevent fraying. Sometimes, a special thread similar to a “soft floss” is used to prevent chafing. The finished product will have a molded look. It is usually inserted inside the bicycle short with a strip of tape to hold it in place. Several manufacturers have developed a one-piece chamois that does not require any seams and avoids any overlapping of material.
Inspection and shipping
3 The completed bicycle short is tested for defects. After passing inspection, it is ready to be packaged and shipped to a retailer.
Perhaps the most important quality control steps occur during the fabric manufacture. Chemical make-up, timing and temperature are essential factors that must be monitored and controlled in order to produce the fabric blend with the desired qualities.
The percentages of the various fibers used in a blended fabric must be controlled to stay within in the legal bounds of the Textile Fiber Identification Act. This act legally defines seventeen groups of man-made fibers. Six of these seventeen groups are made from natural material. They include rayon, acetate, glass fiber, metallics, rubber, and azion. The remaining eleven fabrics are synthesized solely from chemical com¬pounds. They are nylon, polyester, acrylic, modacrylic, olefin, spandex, anidex, saran, vinal, vinyon, and nytril.
Apparel companies will continue to improve both the function and the fashion of bicycle shorts. A number of manufacturers have begun to use sponsored athletes to design, test, and market their products. Designers will continue to experiment with various fiber blends.
Where To Learn More
Ballantine, Richard and Richard Grant. Richards’ Ultimate Bicycle Book. Dorling Kindersley, Inc., 1992.
Chauner, David and Michael Halstead. The Tour De France Complete Book of Cycling. Villard Books, Inc., 1990.
Bradford, C. “Action Softwear,” Health. September, 1988, pp. 45-51.
Herman, Hank. “Cool Threads,” Men’s Health. August, 1990, p. 24.
Smutko, Liz. “The Seat of Your Pants: When It Comes to Cycling Comfort, the Butt Stops Here,” Bicycling. February, 1991, pp. 70-73.