Robergs, R. A., Costill, D. A., Fink, W. J., Williams, C., Pascoe, D. D., Chwalbinska-Moneta, J., & Davis, J. A. (1990). Effects of warm-up on blood gases, lactate and acid-base status during sprint swimming. International Journal of Sports Medicine, 11, 273-278.


A standardized 200 m crawlstroke sprint swim was used to evaluate the effects of warm-up on pH, blood gases, and concentrations of blood lactate and bicarbonate. Eight trained swimmers performed two 200 m swims at 120% VO2max, one without and one with warm-up (400 m crawl at 82% VO2max, 400 m kicking at 45% VO2max, and 4 x 50 m sprints at 111% VO2max).The criterion swims were performed 10 minutes after the experimental conditions.

Warm-up reduced the disturbance in blood acid-base balance during the swimming exercise. There was a slight increase in distance covered in the first 100 m of the warm-up trial (1.7 m that resulted from longer strokes being taken). Warm-up was found to be beneficial and not a hindrance to performance.

Warm-up swimming can be used for reasons other than performance improvements (e.g., environmental familiarization, injury prevention, psychological focusing, neuromuscular facilitation). If it produces additional physiological benefits then its justification is even further supported.

Implication. This article focuses more on the physiology of the response rather than the nature of warm-ups or performance. However, it does display a physiological benefit as well as performance improvement in swims following a warm-up.

"These results indicate that warm-up exercise can reduce the disturbance in blood acid-base balance during 2 min of intense swimming. It is proposed that the acid-base differences resulted from increased oxidative energy metabolism and a subsequent reduction in lactate and CO2 production."

Return to Table of Contents for Physiology of Swimming.