Effects of exercise training on blood pressure: An overview of reviews

The increasing number of systematic reviews (reviews) on exercise training's effects on high blood pressure (HBP) in adults presents methodological limitations and heterogeneous effect estimates. This overview of reviews aims (PROSPERO CRD42021247062) to synthesize findings from high-quality reviews on the benefits and harms of different exercise training modalities on blood pressure and adverse events in adults. This overview was reported according to the PRIOR Statement. We searched MEDLINE, EMBASE, Epistemonikos, and PROSPERO to identify reviews of randomized controlled trials (RCTs) comparing exercise training with active interventions or no exercise in adults. Our outcomes were blood pressure and adverse events. We assessed the certainty of the evidence using the GRADE approach. We included eighteen reviews (15 comparisons; 352 RCTs; 20.518 adults). Any aerobic training, combined training, or isometric resistance training probably resulted in a clinical reduction in blood pressure in adults who either have HBP, cardiovascular disease, or metabolic disease (moderate-certainty evidence). Nine reviews provided very low certainty evidence on safety data. The evidence base underpinning the effects of exercise training on blood pressure outcomes in adults is mostly of very low certainty. This review describes the major limitations of this body of research. Scarce safety data were identified. Further RCTs are needed to strengthen the evidence base supporting this research question.