Since we were interested to know if ankle flexibility is influencing the movements at the ankle during
the dolphin kick, the relationship between the plantar flexion and internal rotation flexibility and
the ankle angles were measured. In the current study, it was demonstrated that both active and passive
plantar flexion ROM were associated with the plantar flexion angles during the downsweep as
there was a significant positive relationship at the maximal plantar flexion time point and the maximal
supination time point. When comparing the amount of ROM with the angles at these time points,
it was apparent that the maximal plantar flexion mobility of the ankle was fully utilized. The measured
angles at these time points were even larger than the measured passive ROM. Possibly, the resistance
of the water was even greater than the manual pressure applied during the passive goniometric
measurement. However, no correlation was present between the internal rotation ROM and the used
flexibility during the dolphin kick. Though, we need to take into account that we cannot fully compare
both measurements since a different assessment technique was utilized.