Armstrong, D. W., Herzig, T. C., Keyser, D. O., Pruschki, D., & Deuswter, P. A. (2003). Correlates of peak body temperature during warm water (37oC) swimming. Medicine and Science in Sports and Exercise, 35(5), Supplement abstract 154.

"During exercise in warm water dissipation of excess metabolic heat is reduced which may limit exercise performance due to an uncompensable heat load" (p. S30). Subjects (M = 6; F = 3) performed a maximal incremental treadmill test. On another day, Ss performed a weighted-tether swim in 37oC water for two 50-min bouts with a 10-min rest between each bout. The tether resistance approximated 50% of treadmill VO2max.

Performance was compromised by the hot water. VO2max was related to core temperature suggesting that there may be workload threshold above which core temperature increases and limits performance.

Implication. Swimming performance is reduced in hot water. Individuals with better aerobic capacities are likely to take longer before performance starts to deteriorate than individuals with lesser capacities.

Return to Table of Contents for Physiology of Swimming.