Effectiveness of Aquatic Exercise in Improving Lower Limb Strength in Musculoskeletal Conditions: A Systematic Review and Meta-Analysis.
To investigate the effectiveness of aquatic exercise in improving lower limb strength in people with musculoskeletal conditions.



A systematic search used 5 databases, including MEDLINE, CINAHL, Embase, SPORTDiscus, and The Cochrane Library.



Randomized controlled trials evaluating aquatic exercise with a resistance training component for adults with musculoskeletal conditions compared with no intervention or land-based exercise were identified. Fifteen studies from the initial yield of 1214 met these criteria.



Data related to participant demographics, study design, and methods, interventions, and outcomes, including numerical means and SDs, were extracted independently by 2 reviewers.



Nine of the 15 studies were of high quality, scoring at least 6 on the Physiotherapy Evidence Database Scale. Limited consideration of the prescription of resistance in the aquatic exercise and application of resistance training principles existed. Low- or very low-quality evidence indicates there was no difference in average effect between aquatic exercise and no exercise in improving hip abductor strength (standardized mean difference [SMD], .28; 95% confidence interval [CI], -.04 to .59), knee extensor strength (SMD, .18; 95% CI, -.03 to .40), knee flexor strength (SMD, .13; 95% CI, -.20 to .45), or lower limb endurance (SMD, .35; 95% CI, -.06 to .77). Low-quality evidence indicates no difference in average effect between aquatic and land exercise for knee extensor (SMD, -.24; 95% CI, -.49 to .02) or flexor strength (SMD, -.15; 95% CI, -.53 to .22).



It is likely that the inadequate application of resistance in water is a significant contributor to the limited effectiveness of aquatic exercise interventions in improving hip and knee muscle strength in people with musculoskeletal conditions. Future research is needed to quantify resistance with aquatic exercises and to determine if using opportunities for greater resistance in aquatic rehabilitation and appropriate resistance training principles can be more effective in improving muscle strength.
Faculty of Health Sciences, School of Exercise Science, Australian Catholic University, Melbourne, VIC, Australia; The Melbourne Sports Medicine Centre, Melbourne, VIC, Australia. Electronic address: Sophie.Heywood@acu.edu.au.
Sophie
S
Heywood
Latrobe University, Melbourne, VIC, Australia.
Jodie
J
McClelland
Faculty of Health Sciences, School of Exercise Science, Australian Catholic University, Melbourne, VIC, Australia.
Benjamin
B
Mentiplay
School of Medicine, University of Maryland, Baltimore, MD.
Paula
P
Geigle
School of Physiotherapy, Australian Catholic University, Brisbane, QLD, Australia.
Ann
A
Rahmann
University of the Sunshine Coast, Sippy Downs, QLD, Australia.
Ross
R
Clark
D015444:Exercise / Q000502:physiology*; D000070633:Hamstring Muscles / Q000503:physiopathology*; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology; D053580:Muscle Strength; D009140:Musculoskeletal Diseases / Q000503:physiopathology* / Q000534:rehabilitation*; D052097:Quadriceps Muscle / Q000503:physiopathology*; D016032:Randomized Controlled Trials as Topic; D055070:Resistance Training; D014867:Water
D014867:Water
Hydrotherapy; Muscle strength; Rehabilitation; Resistance training