A positive correlation between ankle muscle strength and dolphin kick performance was
demonstrated. A flexibility restriction in plantar flexion and internal rotation in the ankles showed
a significant decrease in dolphin kick performance in competitive swimmers. This restriction evoked
a changed movement pattern in the knee towards more flexion. Next to this, while dolphin kicking,
swimmers use the mobility available in the ankle joint. These findings may be of great importance
in future research where swimmers could be imposed to a flexibility or strength program.