Diet-related Behaviors Are Associated with Energy Intake and Body Weight Loss During a Sustained Military Training Exercise (P16-012-19)
OBJECTIVES: Sustained negative energy balance during military operations contributes to degradations in physical and cognitive performance. Characterizing the diet-related behaviors and nutrition knowledge of Soldiers who self-select higher energy intakes during military operations may identify strategies for promoting energy balance. This study aimed to identify diet-related behaviors of Soldiers who self-selected higher energy intakes during a simulated military operation. METHODS: Dietary intake and body weight were measured daily in 54 Soldiers (91% male, BMI 25 ± 4 kg/m(2), 25 ± 4 yr) participating in a 3-d military exercise. During the exercise, Soldiers were provided with military rations (2787–3003 kcal/d), and in some cases consumed items from home or mobile catering. Food frequency and nutrition knowledge questionnaires were completed before the exercise to assess diet quality by HEI-2010 total score and nutrition knowledge, respectively, and questionnaires assessing eating behaviors during the exercise were completed daily and after the exercise. Associations between diet quality, nutrition knowledge, and diet-related behaviors with 1) daily energy intake (EI) and 2) weight loss (∆BW) were determined by backwards elimination multiple linear regression. RESULTS: EI (mean ± SD: 1947 ± 627 kcal/d) and ∆BW (−1.4 ± 1.2%) during the exercise were not correlated. After adjusting for baseline BMI, EI was associated with diet quality (β ± SE: 17 ±9 kcal/d, P = 0.07) and eating frequency (170 ± 86 kcal/d, P = 0.06) and more often intentionally eating foods to improve performance (−389 ± 207 kcal/d, P = 0.07) during the exercise (R(2) = 0.27, P = 0.03). In contrast, greater ∆BW was associated only with more often "not allowing myself to eat" certain foods during the exercise (R(2) = 0.11; −0.8 ± 0.4%, P = 0.04). Nutrition knowledge was not a significant predictor in either model. CONCLUSIONS: Findings suggest that self-selected energy intake and body weight loss during military operations may be associated with ...