status, health, and performance. The committee was then asked to recommend, within specific design constraints, the nutritional composition of a new ration designed for short-term use by soldiers during high-performance, stressful combat missions. The nutritional composition of this new ration would be optimized to best sustain physical and cognitive performance and to prevent possible adverse health consequences. This was to be done recognizing that the ration would likely have a hypocaloric energy content relative to daily expenditure in short-term assault situations—a limitation imposed by ration design and mission constraints. The committee was asked to focus on health issues of highest concern: dehydration, the gastrointestinal gut processes, and the function of the immune system. The committee was also directed to keep in mind the potential health and performance effects on the soldiers subsisting on this ration during its intended use in combat operations.
To address this task, the committee convened a workshop hosted by the USARIEM and the Natick Soldier Center (NSC) in Natick, Massachusetts, August 11–13, 2004, in which speakers addressed the issues brought to the committee by the USARIEM. The agenda is included in Appendix A. These presentations were the basis for the committee’s deliberations and recommendations and are included in this report as individually authored papers in Appendix B.
Among the chief design constraints of this daily ration as required by USARIEM are that it must fit within 0.12 cubic feet and weigh 3 lb (1.36 kg) or less. The ration is targeted for use by male soldiers who have an average body weight of 80 kg, approximately 16 percent body fat, are relatively fit, are within an age range of 18–45 years (average < 25 years), and who have no chronic metabolic disease but may be vulnerable to some common food allergies. During combat operations, the expected daily energy expenditure is 4,000–4,500 kcal/day, achieved through intermittent periods of high-energy expenditure (> 50 percent VO2max) mixed with longer periods of low-intensity movement and sustained for 20 hours per day. The soldier will rely on this ration during missions that last for three to seven days, followed by one to three days of recovery when they will have access to more nutritionally complete meals (i.e., ad libitum food availability served in a field-kitchen setting). The committee has designed this ration with the assumption that soldiers might be deployed to such missions repetitively for a maximum period of one month.
The committee task addressed the following four questions:
Should the energy content of the ration (energy density) be maximized so