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Physical fitness and body composition after a 9-month deployment to Afghanistan
Marilyn A Sharp1, Joseph J Knapik, Leila A Walker
1US Army Research Institute of Environmental Medicine, Military Performance Division, Natick, MA 01760-5007, USA. marilyn.sharp@us.army.mil
Purpose:
To examine change in physical fitness and body composition after a military deployment to Afghanistan.
Methods:
One hundred and ten infantry soldiers were measured before and after a 9-month deployment to Afghanistan for Operation Enduring Freedom. Measurements included treadmill peak oxygen uptake (peak VO2), lifting strength, medicine ball put, vertical jump, and body composition estimated via dual-energy x-ray absorptiometry (percent body fat, absolute body fat, fat-free mass, bone mineral content, and bone mineral density).
Results:
There were significant decreases (P < 0.01) in peak VO2 (-4.5%), medicine ball put (-4.9%), body mass (-1.9%), and fat-free mass (-3.5%), whereas percent body fat increased from 17.7% to 19.6%. Lifting strength and vertical jump performance did not change predeployment to postdeployment.
Conclusions:
Nine months deployment to Afghanistan negatively affected aerobic capacity, upper body power, and body composition. The predeployment to postdeployment changes were not large and unlikely to present a major health or fitness concern. If deployments continue to be extended and time between deployments decreased, the effects may be magnified and further study warranted.
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