Impact of set configurations on hemodynamics, cardiac autonomic, and metabolic responses

Abstract

[Abstract]: Introduction: Isometric exercise (IE) can be used as a non-pharmacologic treatment for blood pressure (BP) reduction. However, the effect of IE set configuration with impulse-to-rest ratio equated on hemodynamic, autonomic, and metabolic responses need to be clarified.Objective: This study compared cardiovascular, autonomic, and metabolic responses in two set configurations of IE with an equalized impulse-to-rest ratio.Methodology: Eleven women (25 ± 3 years old) with normal BP values (systolic BP: 112 ± 10 mmHg; diastolic BP: 71 ± 5 mmHg) performed two equalized protocols in the leg press machine on different days in randomized sequence: Long set configuration (LSC: 4 sets x 2 min of iso-metric contraction x 2 min of rest with 30% 1-RM), and short set configuration (SSC: 16 sets x 30 sec of isometric contraction x 24 sec of rest with 30% 1-RM).Results: During SSC, DBP presented significantly higher values in the first set than LSC (p=0.002). Heart rate, rate pressure product, and cardiac output significantly increased during sets for both protocols. Twenty minutes after protocol, lower values were observed in the mean root square of the successive differences between NN intervals (RMSSD) and mean of the stand-ard deviations for all NN intervals (SDNN) in the LSC configuration in comparison with SSC (p<0.05). In addition, LSC induced significantly higher blood lactate and RPE values during and post-session (p<0.05).Conclusion: The SSC protocol can be better tolerated and targeted for exercise prescription in trained women due to lower hemodynamic, autonomic, and metabolic stress