Abstract
This study aimed to compare the oxygen uptake (VO2), the muscle activity of lower limbs, and the vertical ground reaction force (V-GRF)
of women performing water aerobic exercises at different intensities. 12 young women
performed the experimental protocol, which consisted of 3 water exercises (stationary
running [SR], frontal kick [FK] and cross country skiing [CCS]) at 3 intensities (first
and second ventilatory thresholds and maximum effort). A two-way repeated measures
ANOVA was used. Regarding VO2, different responses between intensities (p<0.001) were found, and values between
exercises were similar. For electromyographic activity (EMG), differences between
intensities for all muscles (p<0.001) were found. Greater EMG signals were observed
in the FK compared to SR for rectus femoris, semitendinosus, vastus lateralis and biceps femoris muscles (p<0.05). Regarding V-GRF, there was an increase in the V-GRF at greater
intensities compared to the first ventilatory threshold (p=0.001). In addition, lower
values were found during CCS compared to the SR and FK exercises (p<0.001). Thus,
greater cardiorespiratory and neuromuscular responses were observed with increasing
intensity. Exercises such as CCS could be used to attenuate the V-GRF; if the purpose
is to reduce the muscular activity of lower limbs at a specific intensity, SR could
be recommended.
Key words
aquatic exercise - underwater EMG - impact forces