Effect of Swimming Training on Cardiorespiratory Endurance Among Junior Athletes at the Warri Aquatics Club, Delta State

Swimming is recognised as one of the most comprehensive aerobic exercises, engaging multiple muscle groups and placing considerable demands on the cardiorespiratory system. This study assessed the effect of structured swimming training on cardiorespiratory endurance among junior athletes at the Warri Aquatics Club, Delta State, South South Nigeria. Forty junior swimmers aged 12 to 17 years were enrolled in a pre-test, post-test quasi-experimental design. Cardiorespiratory endurance was assessed before and after a twelve-week structured swimming training programme using the modified Harvard Step Test and resting heart rate measurements. Lung function was also measured at both time points using a portable spirometer. Paired t-tests were applied for within-group comparisons. Results demonstrated significant improvement in physical fitness index scores, reduction in resting heart rate, and increased forced vital capacity following the twelve-week programme. Improvements were comparable between male and female athletes. Older athletes showed greater absolute gains, though younger participants showed better relative improvement. The study concludes that twelve weeks of structured swimming training significantly enhances cardiorespiratory endurance and lung function in junior athletes in Warri. These findings support investment in school-based and club swimming programmes as a public health and athletic development strategy. Keywords: swimming, cardiorespiratory endurance, lung function, junior athletes, Warri.