The effect of ankle muscle strengthening exercises on underwater dolphin kick (UDK) performance in young swimmers

The purpose of this study was to investigate the effects of ankle muscle strengthening exercises with elastic band on Underwater Dolphin Kick (UDK) performance on young swimmers (N=33, 121,88±25,16 months ). All the swimmers were divided into two groups as study group ( N=17, 121,47±27,12 months) and control group ( N=16, 121,93±24,56 months). Ankle muscle strengthening exercises were applied to study group for 8 weeks (3 days/week). All the assessments were applied for both groups before and after 8 weeks of ankle muscle strengthening exercises that was applied to only study group. Isometric muscle strength (J-Tech Commander handheld dynamometer), core stabilization endurance tests (Prone bridge, left and right side bridges, trunk flexors and extensors tests), functional tests (vertical jump test, standing heel rise test), calculating foot sole area ( Samsung Note 10.1 2014 edition, Adobe Photoshop CS6) were performed. Statistical analysis was performed after swimmers were divided two groups as boys and girls According to statistical analysis results in groups; ankle external rotators and total ankle muscle strength were increased after exercises programme for study group in girls (p<0.05). There was no change in isometric muscle strength for study group in boys (p>0.05). According to statistical analysis results in groups; 5 meters, 10 meters and between 5 – 10 meters UDK performances were increased for study group in girls. In boys, there was no difference for UDK performance between before and after exercise training in both groups. According to correlation between 5 meters UDK performance and other variable difference between pre-training and post training findings; there were negative linear correlation between 5 meters UDK performance and plantarflexors, external rotators and total ankle muscle strength. Simple linear regression analysis indicated that total ankle muscle strength identified as independent predictor of 5 meters UDK performance, explaining 39,2% of the variance. xv It may be use as an efficient approach to include "ankle muscle strengthening exercises with elastic band" in training programme in young swimmers for increase UDK performance.