Effects of Early Aquatic Experience on Motor and Physiological Outcomes in Infants and Children Under 36 Months: A Systematic Review and Meta-analysis

Background and Purpose: Early aquatic experiences may benefit infants and young children with and without developmental delays, but research is limited. Our purpose was to review aquatic experience effects on motor skill, heart rate, and weight gain for participants younger than 3 years of age. Methods: PubMed, Science Direct, and CINAHL were searched from inception through February 2022. Included studies examined infants and children younger than 36 months having aquatic experiences, compared with not having or prior to aquatic experiences, and reported outcomes that included motor skills, heart rate, or infant weight gain. Studies were assessed for quality and potential bias using the PEDro or STROBE checklists. Effect sizes were calculated as the standardized mean difference (Cohen's d ; 95% confidence interval) within and between groups in individual studies and combined across studies using random-effects models. Results: Twelve of 16 articles met the criteria, with 110 participants in studies assessing motor skills, 58 participants in studies assessing heart rate, and 421 newborns in studies assessing infant weight gain. Significant within-group effects were found in motor skills ( d = 1.16; 0.09, 2.23), heart rate ( d = −0.93; −1.54, −0.31), and weight gain ( d = 1.01; 0.09, 1.92). Between-group effects were not significant in motor skills ( d = 0.48; −0.49, 1.44), but were significant in newborn weight gain ( d = 0.63; 0.43, 0.83). No articles reported between-group data for heart rate. Discussion and Conclusions: Moderately strong evidence supports the beneficial effects aquatic experiences have in infants and young children. Limitations include heterogeneity across aquatic experience protocols and measures, retrospective study design for one study, and lack of recommendations for optimal timing and duration for protocols. Additional research is needed to determine effectiveness in subpopulations at developmental risk.