Cordain, L., & Kopriva, R. (1991). Wetsuits, body density, and swimming performance. British Journal of Sports Medicine, 25, 31-33.

To determine the influence of body composition upon swimming performance with and without wetsuits, 14 competitive female swimmers (mean (s.d.) age, 19.9 (0.9) years) were measured for body density while wearing both wetsuits and normal swimsuits. Subjects swam 400 and 1500-m trials with and without wetsuits, randomly, over a 12-day period. Six subjects participated in an additional trial while wearing neoprene leg-bands fitted over the wetsuit (to prevent any air escaping).

Mean (s.d.) subject density without and with wetsuits was 1.048 (.009) and 1.021 (.007) g/ml respectively. Wetsuits reduced (p < 0.05) swim times for the 400 (-4.96%) and 1500 m swim (-3.23%) compared with swimsuit trials. The neoprene bands increased (p < 0.05) swim times relative to swimsuit and wetsuit trials. With wetsuits, swim times were inversely (p < 0.05) related to density for the 400 (r = -0.46) and 1500 m swim (r = -0.54) suggesting that wetsuits increase performance by increasing buoyancy and that lean subjects benefit more from wearing wetsuits than do fatter subjects.

Implication. Different swimmers are assisted disproportionately by flotation devices.

Return to Table of Contents for Hydrodynamics of Swimming.