One single bout of low-intensity isometric handgrip exercise reduces blood pressure in healthy pre- and hypertensive individuals

BACKGROUND: The aim of this study was to investigate the acute effect of one single session of isometric handgrip exercise (IHG) on blood pressure (BP) during daily life activities in healthy adults. METHODS: Fifteen healthy adults with pre- or stage 1 hypertension (10 men; mean age 48 +/- 7.1 years) completed two experimental sessions in random order: one control (rest for 15 minutes) and one low intensity IHG session (4x2 minutes sustained contractions at 30% of maximal volutional contraction interspersed with 1-minute rest intervals). Blood pressure was recorded before each intervention and following the intervention BP was recorded for one hour in the office and thereafter for 6 hours during their daily activities by means of an ambulatory BP device. Physical activity (number of steps and total energy expenditure) was assessed by means of a SenseWear mini device. RESULTS: Systolic BP was higher the first minute after the isometric handgrip exercise but quickly returned to baseline levels after 15 minutes in the office. Over the 7-hour period, systolic blood pressure was significantly lower (-5.4 +/- 7.3 vs. +0.23 +/- 6.9; P<0.05) after IHG compared to the control session. Although not significant, a tendency was observed towards a lower diastolic blood pressure after IHG compared to control (P=0.09). Physical activity behavior was similar on both days (P>0.05). CONCLUSIONS: This study demonstrates that one single bout of IHG can result in an overall reduction in BP during daily activities. More research is needed to confirm these findings and to explain possible mechanisms responsible for these observed changes.