Aquatic exercise is used not only in rehabilitation, but in training of high-performance athletes as well. There are no clear methods or means for operating with such exercise, because their mechanisms cannot be unambiguously explained. The practical values of this kind of exercise are, nevertheless, great – with balance-based workouts we influence the adjustments of motion control on a sensory and motor level. The purpose of the paper was to discover the effects of a balance-based exercise in two different environments – in water and on land. The main goal was to test the effects of a sensorimotor exercise in both environments. Static balance, dynamic balance and jumping power were all taken into consideration during the research.
The research included 31 subjects, who were randomly divided into three groups. The first group performed an exercise programme on land (KOP), the second did the aquatic exercise (VOD), and the third group was used as the control one (KON). The tests were executed before and after a seven-week balance board exercise protocol. Static balance was assessed by measuring the pressure centre with a tensiometric board, dynamic balance was measured by the Y-test of dynamic balance, and jumping power was tested with squat jump (SJ) and counter-movement jump (CMJ).
Normality and homogeneity of variances were calculated for the establishment of the parameters. To assess the effects of the factor of exercise within the groups, a T-test for dependent samples was used; also, a covariance analysis (ANCOVA) was used to assess the factor of the exercise together with the factor of the group, because the median results of the tests were statistically significantly different between the groups. In case of a statistical significance, an LSD post-hoc test was used.
Statistically significant changes within the group were discovered when measuring open-eyed static balance of the aquatic exercise group. An improvement after the dynamic balance exercise was discovered in the KOP group. Jumping power, however, was improved both in the KOP and VOD group. Nevertheless, the covariance analysis did not present statistically significant changes of static and dynamic balance when considering the factor of exercise intervention and the group factor. Statistically significant changes were detected in jumping power, namely in CMJ between the KOP and KON groups, and SJ between the VOD and KON groups. Some differences in CMJ were also shown between the VOD and KON groups.
In the research, it was found that the exercise intervention influences only the explosive power, regardless of it being performed on land or as an aquatic exercise. It is possible that the exercise helped improve intramuscular and intermuscular coordination in the knee and ankle. The improvement in jumping power could also be credited to the improvement of the reflex excitation. When considering the factors of the exercise and the group, no effects on the static and dynamic balance were found. Therefore, it can be deduced that the exercise intervention had no effect on balance. Because there were no significant differences between the KOP and VOD groups in any of the tests, it can be assumed that the effects of the aquatic exercise are similar to effects of exercises performed on land. It can be concluded that aquatic sensorimotor
exercise is reasonable to use in early stages of rehabilitation and also as a means of condition training of high-performance athletes, namely for the development of jumping power. The results of our study indicate that this kind of exercise does not influence static and dynamic balance in trained, adult individuals. However, the study opens up possibilities of further exploration of the effects of exercise in the elderly as well as the injured population, because of their disrupted balance.
It also must be taken into account that the study has its limitations. The exercise programme lasted for only seven weeks. Likewise, a specific test was not used at the beginning and the end of the testing, thus we can not present the actual results of the exercise in specific task. Other disruptive factors were also the small number of participants and the selection of tests, which seemed not to have been sensitive enough.