The role of variables of aquatic training performed in the upright position in improving the lipid profile of adults: systematic review with meta-analysis and meta regression

This systematic review aimed to evaluate the effects of aquatic training (AT) on total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) in adults, compared with control groups (CG), and to determine the possible moderators of the effect of AT on these outcomes. Embase, Cochrane, PubMed, and Scopus were searched until August 2025. Clinical trials comparing the effect of AT with a CG of adults that assessed blood concentrations of TC, TG, LDL, or HDL were included. A random-effects model was used, and effect sizes (ES) were calculated with 95% confidence intervals. Twenty-two studies (697 participants) were included. AT promoted reductions in TC (ES:-0.89), TG (ES:-0.64), and LDL (ES:-1.11) levels and an increase in HDL (ES: 0.53) compared to the CG. The type of training and the presence of progression in its prescription variables did not appear to influence the effects of AT on lipids and lipoproteins. Women exhibited greater reductions in LDL concentrations than mixed samples as a result of AT. Higher weekly frequencies promoted greater reductions in TC, TG, and LDL levels. AT improves the lipid profile in adults. Middle-aged adults tend to experience greater reductions in LDL levels than older individuals, and a longer weekly training frequency is associated with larger decreases in pro-atherogenic lipids and lipoproteins. The type of training, presence of progression, sex, and clinical status do not appear to limit the beneficial effects of AT, although women may achieve greater reductions in LDL than mixed samples. While TC, TG and LDL are more responsive to strength and combined training, HDL is more responsive to aerobic training. Systematic Review Registration Number CRD420160497.