Aquatic Training in Upright Position as an Alternative to Improve Blood Pressure in Adults and Elderly: A Systematic Review and Meta-Analysis

Abstract

Background: Meta-analyses have shown that land training (LT) reduces blood pressure; however, it is not known whether aquatic training (AT) promotes this same effect. Objective: The aim was to conduct a meta-analysis on the effects of AT on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults and elderly and compare them to those of LT and no training [control group (CG)]. Data Sources: Embase, PubMed, Cochrane and Scopus were searched up to May 2017. Study Eligibility Criteria: Studies that evaluated the effect of upright AT (i.e., AT performed in upright position) on the blood pressure of adult individuals and the elderly who did not present with cardiovascular disease (other than hypertension) were included. Data Analysis: Two independent reviewers screened search results, performed data extraction and assessed risk of bias. Random effect was used, and the effect size (ES) was calculated by using the standardized mean difference with a 95% confidence interval. Results: AT promoted a reduction in SBP (ES − 1.47; 95% CI − 2.23 to − 0.70; p < 0.01) compared to CG. This effect is maintained with training progression (ES − 1.52; 95% CI − 2.70 to − 0.33; p = 0.01) and no progression (ES − 1.43; 95% CI − 2.64 to − 0.23; p = 0.02). These effects were significant only in hypertensive (ES − 2.20; 95% CI − 2.72 to − 1.68; p < 0.01), and not in pre-hypertensive individuals. AT promoted a decrease in DBP (− 0.92; 95% CI − 1.27 to − 0.57; p < 0.01) after training with progression (− 0.81; 95% CI − 1.62 to − 0.001; p = 0.04) and no progression (− 1.01; 95% CI − 1.40 to − 0.62; p < 0.01) in pre-hypertensive (− 1.12; 95% CI − 1.53 to − 0.70; p < 0.01) and hypertensive patients (− 0.69; 95% CI − 1.31 to − 0.06; p = 0.03). AT promoted similar reductions in SBP compared to LT; however, reduction of DBP in hypertensive patients was lower (1.82; 95% CI 0.84 to 2.79; p < 0.01). Conclusion: AT promotes blood pressure reduction in adults and elderly. The reduction in SBP in those performing AT is similar to those performing LT, but reduction of DBP is lower in the AT group compared to that in the LT group. Systematic Review Registration Number: CRD42016049716.