Effects of run-training and swim-training at similar absolute intensities on treadmill VO2max.

Thirty-seven sedentary males, aged 28-35 yr, were either run-trained, swim-trained, or served as controls in an 11 1/2-wk training study. Runners and swimmers exercised once a d, 3 d.wk, at a heart rate (HR) intensity equivalent to 75% of their treadmill VO2max. Treadmill maximal oxygen consumption (VO2max), submaximal cardiorespiratory response, and body composition parameters were measured before and following the training period. Runners, swimmers, and controls experienced a significant increase in treadmill VO2max over the 11 1/2-wk study period. The 28 and 25% increases observed for the runners and swimmers, respectively, were significantly greater than the 5% increase observed for the controls (P less than 0.0001). Runners and swimmers did not differ significantly from each other with respect to this increase in VO2max; nor did they demonstrate significant changes in respiratory exchange ratio (RER) at VO2max between tests. The run-trained and swim-trained groups both experienced a decrease in HR at a standard submaximal walking workload but did not differ significantly from each other. Controls showed no significant change in submaximal exercise response. A significant difference was observed among groups (P less than 0.01) for change in percent body fat. Changes in lean and fat weight over the training period were significant for both the runners (P less than 0.002) and swimmers (P less than 0.03) but not for the controls.(ABSTRACT TRUNCATED AT 250 WORDS)