Weight Loss Before Military Training May Cut Injury Risk

TOPLINE:

Army recruits who lost excess weight to enter military training experienced fewer musculoskeletal injuries (MSKIs), particularly in the lower extremities, during basic combat training than those who did not lose weight to join the service.

METHODOLOGY:

• The nation’s obesity epidemic means that fewer individuals meet the US Army’s weight and body-fat standards for entering basic combat training. Only 29% of 17- to 24-year-olds in the country would have qualified to join the military in 2018, with overweight and obesity among the leading disqualifying factors.
• Researchers analyzed data from 3168 Army trainees (mean age, 20.96 years; 62.34% men; mean maximum-ever BMI, 26.71) to examine the association between weight loss before enlistment and rates of MSKI during basic combat training.
• Trainees completed a baseline questionnaire that asked whether the person lost weight to enter the Army and included follow-up questions about the amount of weight lost, duration of weight loss, methods used, and prior physical activity.
• MSKIs were classified as any injury to the musculoskeletal system and further categorized by body region (lower extremities, upper extremities, spine/back, and other areas, including the torso and head/neck).
• Researchers identified MSKIs from medical records collected throughout basic combat training and for up to 6 weeks afterward to capture injuries that occurred during training but were documented only after its completion.

TAKEAWAY:

• Overall, 829 trainees (26.16%) reported losing weight to enter the Army, and they tended to have higher mean maximum-ever BMI, body-fat percentage, and lean mass compared with those who did not lose weight to join the service. The mean weight loss was 9.06 kg at a rate of 1.27 kg/wk among the 723 trainees with complete data.
• The most commonly reported weight-loss methods were exercising more (83.72%), changing diet (61.04%), skipping meals (39.32%), and sweating using a sauna or rubber suit (25.57%).
• Trainees who lost weight to join the service had a lower risk of any MSKI (hazard ratio [HR], 0.86) and lower extremity MSKIs (HR, 0.84) during training than those who did not lose weight to enter the Army. No difference was found between the two groups in the risk of upper extremity, spine/back, or other MSKIs.
• Among trainees who lost weight to join the Army, the amount of time it took to lose weight was not associated with the risk for any MSKI or region-specific MSKIs.

IN PRACTICE:

“The findings highlight that losing excess weight before entering military training may reduce MSKI risk for incoming recruits, enforcing the benefits of healthy weight loss programs,” the authors wrote.

SOURCE:

The study, led by Vy T. Nguyen, MS, DSc, Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, was published online in Obesity.

LIMITATIONS: 

The study did not assess whether the association between weight loss and the rate of MSKIs persisted over long-term military service. How the two most frequently reported weight loss methods — increased exercise and dietary changes — may have influenced the observed association remains unclear. Medical records may not have captured all MSKIs if trainees did not seek medical care due to concerns about graduating on time or being placed on limited duty.

DISCLOSURES:

The study was supported by the US Army Medical Research and Development Command’s Military Operational Medicine Program. Two authors received support from the funder.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.