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Vertical ground reaction force during water exercises performed at different intensities
C L Alberton1, M P Tartaruga, S S Pinto
1School of Physical Education, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
International Journal of Sports Medicine
|April 4, 2013
Summary
Water aerobics significantly reduce peak vertical ground reaction force (V-GRF(peak)) and impulse compared to land exercises. This makes water exercises a safe option for individuals needing to minimize impact forces during training.
Area of Science:
- Biomechanics
- Exercise Physiology
- Sports Science
Background:
- Vertical ground reaction force (V-GRF) and impulse are critical biomechanical parameters in exercise.
- Understanding the impact of exercise environment on these forces is essential for injury prevention and performance optimization.
- Water-based exercises offer a low-impact alternative, but direct comparisons of V-GRF and impulse with land-based equivalents are needed.
Purpose of the Study:
- To compare peak vertical ground reaction force (V-GRF(peak)) and impulse between aquatic and dry land environments.
- To investigate the effects of different exercise intensities (cadences) on these forces in both environments.
- To evaluate biomechanical differences across various water aerobic exercises.
Main Methods:
- 15 young women participated in a randomized crossover study.
- Three water aerobic exercises (stationary running, frontal kick, cross country skiing) were performed at three cadences (VT1, VT2, max effort) in both aquatic and dry land settings.
- Two-way and three-way repeated measures ANOVA were used to analyze impulse and V-GRF(peak) data.
Main Results:
- Significantly lower V-GRF(peak) and impulse were observed in the aquatic environment (p<0.001).
- All cadences showed significant differences in V-GRF(peak) and impulse in both environments, with minor exceptions in aquatic settings.
- Cross country skiing in water yielded lower V-GRF(peak) compared to other aquatic exercises (p<0.001).
Conclusions:
- Water aerobic exercises are safe for individuals aiming to minimize vertical ground reaction forces.
- The exercise type and intensity prescribed in water aerobics training significantly influence V-GRF(peak) and impulse.
- Aquatic environments substantially reduce impact forces, highlighting their therapeutic and rehabilitative potential.
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