HIGH-INTENSITY RESISTANCE EXERCISE BLUNTS CARDIOVASCULAR RESPONSIVENESS
Alderman, B. L., & Arent, S. M. (June 02, 2010). Dose-response effects of resistance exercise on cardiovascular responses to laboratory stressors. Presentation 1815 at the 2010 Annual Meeting of the American College of Sports Medicine, Baltimore, Maryland; June 2-5.
This study assessed the effectiveness of an acute bout of resistance exercise for attenuating cardiovascular responses to a laboratory stressor and examine a potential dose-response relationship of resistance exercise intensity. Male and female Ss (N = 62) were randomly assigned into control, 40%, 70%, and 100% of 10-repetition maximum (10 RM) resistance exercise groups. During the initial session a 10 RM was found for the following exercises: bench press, lat pull down, shoulder press, leg extension, leg press, and leg curl. During the second session, Ss completed 3 x 10 repetitions of each exercise corresponding to their intensity-based group assignment. Thirty minutes following completion of the exercise bout, Ss completed a psychological stress protocol consisting of a 6-minute verbal serial subtraction task and a 6-minute interpersonal speech. Measures of heart rate, heart rate variability, and systolic and diastolic blood pressures were assessed during the baseline, stress, and recovery periods.
There was a significant linear effect of resistance exercise intensity on heart rate and systolic blood pressure reactivity and heart rate recovery to stress. There was a significantly greater parasympathetic dominance following 70% and 100% 10 RM groups that persisted through the laboratory stressor.
Implication. High-intensity resistance-exercise bouts result in blunted cardiovascular reactivity and greater heart rate recovery to mental stressors. Greater parasympathetic cardiac control following resistance exercise of higher intensities (i.e., parasympathetic rebound) may explain the attenuated cardiovascular stress responses.