In this study, we examined the correlations between selected markers of isometric training intensity and subsequent reductions in resting blood pressure. Thirteen participants performed a discontinuous incremental isometric exercise test to volitional exhaustion at which point mean torque for the final 2-min stage (2min-torquepeak) and peak heart rate peak (HRpeak) were identified. Also, during 4 weeks of training (3 sessions per week, comprising 4 2 min bilateral leg isometric exercise at 95% HRpeak), heart rate (HRtrain), torque (Torquetrain), and changes in EMG amplitude (ΔEMGamp) and frequency (ΔEMGfreq) were determined. The markers of training intensity were: Torquetrain relative to the 2min-torquepeak (%2min-torquepeak), EMG relative to EMGpeak (%EMGpeak), HRtrain ΔEMGamp, ΔEMGfreq, and %MVC. Mean systolic (-4.9 mmHg) and arterial blood pressure (-2.7mmHg) reductions correlated with %2min-torquepeak (r = -0.65, P = 0.02 and r = -0.59, P = 0.03), ΔEMGamp (r = 0.66, P = 0.01 and r = 0.59, P = 0.03), ΔEMGfreq (r = -0.67, P = 0.01 and r = -0.64, P = 0.02), and %EMGpeak (systolic blood pressure only; r = -0.63, P = 0.02). These markers best reflect the association between isometric training intensity and reduction in resting blood pressure observed after bilateral leg isometric exercise training.
Devereux, G. R., Wiles, J. D., & Swaine, I. (2011). Markers of isometric training intensity and reductions in resting blood pressure. Journal of Sports Sciences, 29(7), 715-724. https://doi.org/10.1080/02640414.2011.552113