Effects of isometric handgrip training on blood pressure among hypertensive patients seen within public primary healthcare: a randomized controlled trial

ABSTRACT

ABSTRACT BACKGROUND: Meta-analyses have demonstrated that isometric handgrip training (IHT) decreases blood pressure in hypertensive individuals. Nonetheless, most studies were conducted in laboratory settings and its effects in real-world settings remain unclear. OBJECTIVE: To analyze the effects of IHT on office and ambulatory blood pressure in hypertensive patients attended within primary healthcare. DESIGN AND SETTING: Randomized controlled trial conducted in primary healthcare units within the Family Health Program, Petrolina, Pernambuco, Brazil. METHODS: 63 hypertensive patients (30-79 years old; 70% female) were randomly allocated into IHT or control groups. IHT was performed three times per week (4 x 2 minutes at 30% of maximal voluntary contraction, one-minute rest between bouts, alternating the hands). Before and after the 12-week training period, office and ambulatory blood pressure and heart rate variability were obtained. The significance level was set at P < 0.05 (two-tailed testing) for all analyses. RESULTS: IHT significantly decreased office systolic blood pressure (IHT 129 ± 4 versus 121 ± 3 mmHg, P < 0.05; control 126 ± 4 versus 126 ± 3 mmHg, P > 0.05), whereas there was no effect on diastolic blood pressure (IHT 83 ± 3 versus 79 ± 2 mmHg, P > 0.05; control 81 ± 3 versus 77 ± 3 mmHg, P > 0.05). Heart rate variability and ambulatory blood pressure were not altered by the interventions (P > 0.05 for all). CONCLUSION: IHT reduced office systolic blood pressure in hypertensive patients attended within primary care. However, there were effects regarding diastolic blood pressure, ambulatory blood pressure or heart rate variability. CLINICALTRIALS.GOV IDENTIFIER NCT03216317.