Performance Enhancement in Freestyle Swimming through Plank Exercise and Fins Utilization: Case Study of a Swimming Club in Medan

Swimming is a sport that requires the integration of technical skill, muscular strength, core stability, and cardiovascular endurance to achieve optimal performance. This study aimed to examine the impact of integrating plank exercises with the utilization of swim fins on the 50-meter freestyle swimming speed of adolescent swimmers in a swimming club in Medan, Indonesia. A quasi-experimental design with a pre-test and post-test control group was established. Thirty-six swimmers were randomly assigned to either the experimental group (n = 18), which received plank training and used fins during practice, or the control group (n = 18), which continued conventional training. The intervention lasted for 16 sessions. Data was analyzed using Shapiro-Wilk normality tests, Levene's homogeneity test, paired-sample t-tests, and independent-sample t-tests. The results showed that the experimental group observed a statistically significant increase in swimming speed (mean difference: 0.6575 seconds, p < 0.05), greater than that of the control group (mean difference: 0.18875 seconds, p < 0.05). The results suggest that plank exercises and fins utilization contribute to enhanced core stability, improved body alignment, and increased propulsion efficiency during freestyle swimming. This study highlights the potential of integrating dry-land core training and in-water assistive devices to optimize swimming performance. Future research should involve larger sample sizes, longer interventions, and additional biomechanical or physiological assessments to further validate these findings and explore underlying mechanisms.