Fluid Loss and Body Rehydration Effects on Marksmanship Performance
Abstract
Effects of body weight loss (BWL) and a rehydration (REHYD) on marksmanship after exercising in the heat (91 F, 20.4% humidity) in MOPP IV were assessed. Sixteen male soldiers walked (2.5 MPH) for six 50/10 minute work/rest cycles. Water intake was ad lib. Subjects were tested on the Weaponeer M16A1 rifle simulator in NO MOPP and MOPP IV pre and post exercise. Subjects fired two 9-round shot groups at a simulated 25-meter zeroing target in each condition. Shot groups were digitized to obtain 4 marksmanship measures: average distance from center of mass (DCM), tightness of shot group (TSG), horizontal TSG and vertical TSG. Two post hoc groups were formed for %BWL/hr and % REHYD using the median as the cutoff point. Post exercise, DCM was significantly greater in the low %REHYD group compared to the high %REHYD group (p<.03). Similarly, post exercise the high %BWL/hr group DCM was significantly greater than the low group (p<.04). A significant (p<.01) clothing (MOPP IV vs. NO MOPP) by administration (pre vs. post exercise) interaction for DCM was found. The results demonstrate that exercising in the heat of MOPP IV significantly impairs marksmanship. Individuals with a high 5BWL/hr as well as those who do not rehydrate adequately are significantly degraded in marksmanship.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1989
- Accession Number
- ADA212154
Entities
People
- Patricia C. Szlyk
- Terry M. Rauch
- William J. Tharion
Organizations
- United States Army Research Institute of Environmental Medicine