Energy requirements of US Army Special Operation Forces during military training

Abstract

Special Operations Forces (SOF) regularly engage in physically demanding combat operations and field training exercises, resulting in high daily energy expenditure, and thus increased energy requirements. However, the majority of studies assessing energy requirements of SOF have been conducted on soldiers going through intense SOF initiation training. The objective of the current investigation was to determine the energy expenditure of SOF conducting military training operations. Thirty-one soldiers taking part in Pre-Mission Training (PMT n = 15) and Combat Diver Qualification Courses (CDQC n = 16) volunteered to participate in this observational study. Energy expenditure was determined using doubly labeled water. Body weight (83 ± 7 kg) remained stable during both training periods. Overall energy expenditure adjusted for body composition was 17,606 ± 2326 kJ·day(-1). Energy expenditure was 19,110 ± 1468 kJ·day(-1) during CDQC and 16,334 ± 2180 kJ·day(-1) during PMT, with physical activity levels of 2.6 ± 0.2 and 2.2 ± 0.3 during CDQC and PMT, respectively. Compared to the Military Dietary Reference Intakes for energy (13,598 kJ·day(-1)), these data are in agreement with previous reports that energy requirement for SOF Soldiers exceed that of the average soldier.

Figure 1

Experimental design. DLW: doubly labeled water.

Figure 2

Total daily energy expenditure. Values are mean ± SD. (□) resting metabolic rate, () diet-induced thermogenesis, (■) activity-induced energy expenditure. ⁺ Total daily energy expenditure different from MDRI, P < 0.05; ^† MDRI; military dietary reference intakes 13,598 kJ·day⁻¹.