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Ground Reaction Forces During Reduced Gravity Running in Parabolic Flight
Aerospace Medicine and Human Performance
|July 20, 2017
Summary
Treadmill running in simulated lunar and Martian gravity may not protect bones. Reduced gravity decreased ground reaction forces, suggesting it is not osteo-protective exercise for space missions.
Area of Science:
- Space exploration
- Human physiology
- Biomechanics
Background:
- Treadmills are used in spaceflight to prevent musculoskeletal changes.
- Future lunar and Martian missions may include treadmills in habitats.
Purpose of the Study:
- To assess osteogenic effects of treadmill exercise in reduced gravity.
- To measure ground reaction forces (GRFs) during running in simulated lunar and Martian gravity.
Main Methods:
- Eight subjects ran at 6 mph on a treadmill during parabolic flights simulating Martian and lunar gravity.
- Ground reaction forces (GRFs) were measured.
Main Results:
- Stride length increased as gravity decreased.
- GRF peaks decreased significantly with reduced gravity (0.156 and 0.196 bodyweights per 1/10 g).
Conclusions:
- Unloaded treadmill running in lunar and Martian gravity is unlikely to be osteo-protective.
- Findings suggest current treadmill protocols may need adaptation for long-duration space missions.
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