D-16 Thematic Poster - Sustaining Warfighter Performance: JUNE 2, 2011 1:00 PM - 3:00 PM: ROOM: 304
Small Unit Tactics (SUT), an intense 64-d phase during the Special Forces Qualification Course, trains Soldiers in performing typical combat missions. This training is designed to realistically simulate combat operations. By assessing energy expenditures of Soldiers in SUT, we can obtain insights into nutritional requirements of Soldiers conducting combat operations. To date no study has systematically examined energy balance during these 9 weeks of rigorous training.
PURPOSE: Measure energy expenditure / intake and changes in body composition of Soldiers participating in the SUT course.
METHODS: Total daily energy expenditure (TDEE) was measured using doubly labeled water (D2 18O). Energy intake (EI) was calculated by subtracting energy in returned foods from known energy in distributed foods. Body composition was assessed before and at completion of SUT, using skinfolds.
RESULTS: TDEE data was collected from 46 Soldiers, while pre/post body composition data was limited to 28 Soldiers due to attrition. Participants were 28 ± 4 years old, 177 ± 6 cm tall and had an initial body weight of 84 ± 7 kg. Mean TDEE was 4,501 ± 993 kcal/d (18.8 ± 4.2 kJ/d), with daily EI being 3803 ± 932 kcal/d (15.9 ± 3.9 kJ/d) (p < 0.01). The ∼15% energy deficit resulted in an average 4.2 kg weight loss (p < 0.01), with fat mass (FM) decreased 2.8 kg (p < 0.01), and a reduction in fat-free mass (FFM) of 1.4 kg (p < 0.02), representing 59 and 41% of total weight loss, respectively.
CONCLUSIONS: The high TDEE associated with SUT training and inadequate EI leads to an energy deficit which promotes reductions in weight, FM and FFM, similar to changes reportedly experienced during combat training. Soldiers may benefit from an altered feeding regimen or utilization of different rations to maintain energy balance during SUT. Interventions that successfully mitigate this energy deficit and prevent weight and fat free loss during SUT may also be effective nutritional countermeasures for use during combat operations.
Supported by U.S. Army Medical Research and Material Command