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Exertional heat illness among overweight U.S. Army recruits in basic training
Sheryl A Bedno1, Yuanzhang Li, Weiwei Han
1Department of Epidemiology, Walter Reed Army Institute of Research, Silver Spring, MD, USA. sheryl.bedno@usuhs.mil
Aviation, Space, and Environmental Medicine
|February 6, 2010
Summary
Military recruits with excess body fat face a significantly higher risk of heat illness. This finding highlights the need to address body composition standards to improve soldier safety during training.
Area of Science:
- Military medicine
- Environmental physiology
- Occupational health
Background:
- Heat illness incidence remains high in the U.S. military despite existing preventive measures.
- Increasing prevalence of overweight recruits may exacerbate heat-related events.
- This study investigates the link between exceeding body fat standards and heat illness risk.
Purpose of the Study:
- To compare the risk of heat illness in U.S. Army recruits who exceeded body fat standards versus those who met them.
- To analyze incidence and outpatient utilization for heat illness among male recruits.
- To assess the impact of excess body fat on heat illness risk during basic training.
Main Methods:
- A cohort of 9,667 male U.S. Army recruits (826 with excess body fat, 8,841 qualified) was studied from February 2005 to September 2006.
- Recruits underwent a preaccession fitness test (step test, push-up challenge).
- Incidence and outpatient usage for heat illness were compared between groups at 90 days of service.
Main Results:
- Male recruits with excess body fat had a 3.63 times higher odds of heat illness compared to qualified recruits.
- The rate ratio for heat illness incidence in men with excess body fat was 7.25.
- A significant increase in heat illness and outpatient utilization was observed in male recruits exceeding body fat standards.
Conclusions:
- Excess body fat is a significant risk factor for heat illness and outpatient visits among male military recruits.
- Approximately 70% of the relative risk for heat illness in these recruits was linked to exceeding body fat standards.
- Findings suggest potential implications for military accession policies and training protocols regarding body composition.
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