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Updated: Jun 4, 2026
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Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
Joint forces and torques when walking in shallow water.
Maria Isabel Veras Orselli1, Marcos Duarte
1Institute of Physics and School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil.
Journal of Biomechanics
|February 22, 2011
Summary
Walking in chest-high water significantly reduces lower limb joint forces and torques compared to land. This study quantifies these reductions, supporting water walking for low-impact exercise.
Area of Science:
- Biomechanics
- Human Movement Science
- Hydrotherapy
Background:
- Understanding the biomechanical effects of aquatic exercise is crucial for rehabilitation and training.
- Previous research has not fully quantified internal joint forces and torques during water walking, considering drag forces.
Purpose of the Study:
- To estimate and compare internal net joint forces and torques in the lower limbs and pelvis during walking on land versus in shallow water.
- To investigate the influence of water drag forces on lower limb biomechanics during gait.
Main Methods:
- Two-dimensional sagittal plane gait analysis using force plates and video cameras.
- Inverse dynamics calculations to estimate joint forces and torques at the ankle, knee, and hip.
- Comparison of data from 10 healthy adults walking at comfortable speeds on land and in chest-high water.
Main Results:
- Apparent weight in water was 35% of land weight; walking speed was 2.7 times slower.
- Significant reductions in ankle and knee joint torques and powers were observed in water compared to land.
- Compressive and shear joint forces were approximately three times lower during water walking.
Conclusions:
- Water walking leads to substantially lower joint loading compared to land walking.
- The findings support the use of aquatic environments for low-impact physical activity and rehabilitation.
- Depth-dependent reductions in joint torques highlight the benefits of water immersion for joint unloading.
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