Impact of Nonpharmaceutical Interventions During the COVID-19 Pandemic on Medically Attended Acute Respiratory Infection: The U.S. Naval Academy Experience.

INTRODUCTION: Medically attended acute respiratory infections (MAARI) at the U.S. Naval Academy increase during Plebe Summer, a training program for incoming freshmen. Because of COVID-19, extensive nonpharmaceutical interventions (NPI) were implemented during 2020 Plebe Summer. METHODS: We reviewed MAARI counts in weeks 22-45 from 2012 to 2020 and compared counts in pandemic (2020) vs. pre-pandemic (2012-2019) periods. RESULTS: From 2012 to 2019, an average of 1,642 MAARI cases occurred annually. In 2020, 443 MAARI cases occurred. NPI use was associated with a 77% reduction in MAARI. CONCLUSIONS: During a high-risk military training period, routine NPI use was associated with a major reduction in MAARI.

Impact of physical fitness and body composition on injury risk among active young adults: A study of Army trainees.

OBJECTIVES: To determine the combined effects of physical fitness and body composition on risk of training-related musculoskeletal injuries among Army trainees. DESIGN: Retrospective cohort study. METHODS: Rosters of soldiers entering Army basic combat training (BCT) from 2010 to 2012 were linked with data from multiple sources for age, sex, physical fitness (heights, weights (mass), body mass index (BMI), 2 mile run times, push-ups), and medical injury diagnoses. Analyses included descriptive means and standard deviations, comparative t-tests, risks of injury, and relative risks (RR) and 95% confidence intervals (CI). Fitness and BMI were divided into quintiles (groups of 20%) and stratified for chi-square (χ2) comparisons and to determine trends. RESULTS: Data were obtained for 143,398 men and 41,727 women. As run times became slower, injury risks increased steadily (men=9.8-24.3%, women=26.5-56.0%; χ2 trends (p<0.00001)). For both genders, the relationship of BMI to injury risk was bimodal, with the lowest risk in the average BMI group (middle quintile). Injury risks were highest in the slowest groups with lowest BMIs (male trainees=26.5%; female trainees=63.1%). Compared to lowest risk group (average BMI with fastest run-times), RRs were significant (male trainees=8.5%; RR 3.1, CI: 2.8-3.4; female trainees=24.6%; RR 2.6, CI: 2.3-2.8). Trainees with the lowest BMIs exhibited highest injury risks for both genders and across all fitness levels. CONCLUSIONS: While the most aerobically fit Army trainees experience lower risk of training-related injury, at any given aerobic fitness level those with the lowest BMIs are at highest risk. This has implications for recruitment and retention fitness standards.