Isometric handgrip (IHG) training‐induced reductions in resting blood pressure: reactivity to a 2‐minute handgrip task identifies responders and non‐responders in young normotensive individuals (LB661)

Abstract

In people with hypertension, systolic blood pressure (SBP) reactivity to an isometric handgrip task (IHGT), but not a cold pressure task (CPT), is predictive of IHG training‐induced reductions in resting SBP. To investigate whether these findings could be extended to include young normotensives, resting BP and BP reactivity to an IHGT (2‐minute sustained contraction at 30% maximal voluntary contraction, MVC) and a CPT (2‐minute hand immersion in a cold water bath) were measured prior to and following 10 weeks of IHG training (4, 2‐minute IHG contractions at 30% MVC, using alternating hands, interspersed with 1‐minute rest periods, 3X/week) in 7 normotensive individuals (3 females, 4 males; age=25 ± 5.7 years). BP reactivity was derived by calculating the difference between peak stress BP and mean baseline resting BP. Significant training‐induced reductions in resting SBP (p<0.001) were strongly correlated with pre‐training SBP reactivity to the IHGT (r=‐0.8, p=0.03), but not the CPT (r= 0.2, p=0.6). These preliminary findings suggest that SBP reactivity to a short and simple handgrip task can be used as a predictive tool to identify who will respond best to IHG training. It might be possible to further explore how the IHG training stimulus could be optimized in non‐responders, to ensure that they too, experience reductions in resting BP.Grant Funding Source: Supported by University of Windsor Kinesiology seed grant