Isometric handgrip training does not reduce BP in hypertensive patients
Isometric handgrip exercise, performed according to a typical protocol, is not effective in lowering blood pressure (BP) in patients with hypertension, a recent study has found. On the other hand, aerobic exercise, even when uncontrolled and unsupervised, has been found to significantly reduce ambulatory and office BP.
For the first time, researchers compared the effects of isometric handgrip training and aerobic exercise by randomly assigning a total of 75 hypertensive patients to one of the following 12-week programmes: Isometric handgrip training five times weekly (two contractions of 2 min at 30 percent of maximal power with each arm); sham-handgrip training five times weekly (two contractions of 2 min at 5 percent of maximal power with each arm); and aerobic exercise training of 30 min three to five times per week.
All participants had office BP measurement, 24-hour ambulatory BP measurement and noninvasive assessment of arterial compliance and systemic vascular resistance at baseline and after 12 weeks. There were no between-group differences in baseline epidemiological and haemodynamic characteristics.
Aerobic exercise resulted in a significant reduction of systolic 24-hour (S)BP (p=0.025), office SBP (p=0.03), systemic vascular resistance (p=0.001) and small artery elasticity index (p=0.005). However, no statistically significant changes in these parameters were seen in the isometric exercise and the sham exercise groups (p>0.05 for each).
These results support that of the study by Ash and colleagues, who found that isometric handgrip resistance exercise was not an effective antihypertensive therapy. They also stated that aerobic exercise should continue to be recommended as the primary exercise modality for its immediate and sustained BP benefits. [J Hypertens 2017;35:291-299]