Effects of Single vs. Multiple Bout Moderate Exercise Training on Heart Rate during Submaximal Exercise in Women

Abstract

Previous research has shown exercise training beneficially improves heart rate (HR) at rest and during submaximal levels of exercise. However, it is unclear if HR responds similarly to multiple bout training compared to single bout training. PURPOSE: This study investigated the effects of single bout (1x30 minutes) vs. multiple bout (3x10 minutes) moderate exercise training on resting HR and during 20 minutes of submaximal exercise HR. METHODS: Thirty-nine women participated in a 16-week aerobic training program, either one 30-minute (n=20, 50.5 ± 1yr.) or three 10-minute bouts (n=19, 46.9 ± 1.3 yr.) at 65% of VO2peak. Prior to and post training, the subjects completed a 20-minute submaximal exercise (65% VO2peak) session where HR was measured at 3 time points (minute 9, 15 and 20). Resting HR was also measured in the supine position after 25 minutes of rest. RESULTS: Resting and submaximal HR, at all 3 timepoints, decreased significantly (p<0.01) with training. Both single and multiple bouts of exercise groups decreased resting HR and exercise HR at 9 minutes (p<0.01), with no training group differences. However at minutes 15 and 20 of submaximal exercise, there was a significant (p<0.02) training effect. The submaximal HR for the single bout exercise group decreased moreso than the multiple bout training group.TableCONCLUSION: Both single and multiple bouts of exercise training decrease resting HR; however, the reduction in submaximal exercise HR is training duration dependent. Once again this reiterates the importance of specificity of training.