Low Energy Availability Prevalence, Dietary Habits, and Sleep in Female Army ROTC Cadets

Low energy availability (LEA) results in numerous health and performance decrements. While a high prevalence of LEA and sleep disturbance has been observed in male Army Reserve Officers' Training Corps (ROTC) cadets, no data exists in females. This study aimed to determine LEA prevalence, dietary habits, and sleep quantity and quality in female U.S. ROTC cadets. Following an overnight fast, ten cadets (22±4 yrs, 166.0±6.1 cm, 67.1±9.1 kg, 26.1±6.2% body fat, 49.2±4.8 kg fat-free mass (FFM)) had their body composition and resting metabolic rate measured. Validated questionnaires assessed LEA symptoms and sleep. Under free-living conditions, exercise energy expenditure (EEE) and sleep were quantified via accelerometers for 7-days. Concurrently, energy intake (EI) was assessed via digital food records and evaluated relative to the Military Dietary Reference Intakes (MDRIs). Cadets consumed 1983±706 kcal·d^-1 with a mean EEE of 482±110 kcal·d^-1. EA was 30.6±13.2 kcals·kg^-1 FFM with 40% presenting with LEA (≤ 30 kcals·kg^-1 FFM) and another 50% in a suboptimal EA state (30-45 kcals·kg^-1 FFM). Dietary analysis indicated 30%, 40%, 80%, and 10% of cadets met MDRIs for calories, carbohydrate, protein, and fat, respectively. Cadets slept 373±100 min·d^-1, with 20% of cadets meeting the Army recommendation for sleep. Sleep questionnaires indicated that 60% of cadets experienced poor sleep quality and 30% had poor sleep behavior. In the present study, all but one cadet was in a low or suboptimal EA state, a high prevalence of sleep disturbance was observed, and most cadets did not meet MDRIs for energy and macronutrient intakes.