Effects of isometric resistance training on resting blood pressure: Individual participant data meta-Analysis

Abstract

Background:Previous meta-Analyses based on aggregate group-level data report antihypertensive effects of isometric resistance training (IRT). However, individual participant data meta-Analyses provide more robust effect size estimates and permit examination of demographic and clinical variables on IRT effectiveness.Methods:We conducted a systematic search and individual participant data (IPD) analysis, using both a one-step and two-step approach, of controlled trials investigating at least 3 weeks of IRT on resting systolic, diastolic and mean arterial blood pressure.Results:Anonymized individual participant data were provided from 12 studies (14 intervention group comparisons) involving 326 participants (52.7% medicated for hypertension); 191 assigned to IRT and 135 controls, 25.2% of participants had diagnosed coronary artery disease. IRT intensity varied (8-30% MVC) and training duration ranged from 3 to 12 weeks. The IPD (one-step) meta-Analysis showed a significant treatment effect for the exercise group participants experiencing a reduction in resting SBP of-6.22mmHg (95% CI-7.75 to-4.68; P<0.00001); DBP of-2.78mmHg (95% CI-3.92 to-1.65; P=0.002); and mean arterial blood pressure (MAP) of-4.12mmHg (95% CI-5.39 to-2.85; P<0.00001). The two-step approach yielded similar results for change in SBP-7.35mmHg (-8.95 to-5.75; P<0.00001), DBP MD-3.29mmHg (95% CI-5.12 to-1.46; P=0.0004) and MAP MD-4.63mmHg (95% CI-6.18 to-3.09: P<0.00001). Sub-Analysis revealed that neither clinical, medication, nor demographic participant characteristics, or exercise program features, modified the IRT treatment effect.Conclusion:This individual patient analysis confirms a clinically meaningful and statistically significant effect of IRT on resting SBP, DBP and mean arterial blood pressure.