Scenarios that Illustrate Potential Usefulness of Food Components to Enhance Performance
On the following pages are seven scenarios, based on Army research experience, which illustrate possible applications of food components to enhance performance. These scenarios were developed at the request of the Committee on Military Nutrition Research (CMNR) during planning for the workshop, An Evaluation of Potential Performance Enhancing Food Components for Operational Rations, in order to provide a framework for the understanding of the committee members and speakers. These scenarios are presented to enable the reader to better understand the context within which this report was developed.
How might nutrients be employed to enhance the mental performance of military forces? On occasion drugs have been effectively employed to enhance the mental performance of soldiers and other professionals performing similar duties. Therefore, in some instances, the effective use of drugs as performance enhancing agents may provide a model for the use of nutrients.
Scenario: Operations by all types of units during moderate and intensive combat or other continuous operations. Not only do combat soldiers engaged in combat operations need to continuously perform for many days with minimal rest, but critical support units (medical, supply, etc.) also need to work continuously. Severe sleep loss in inevitable. Virtually every form of cognitive and psychomotor performance deteriorates under such conditions. While impaired performance of combat troops would have severe consequences, the failure of support units to accomplish their duties could also be catastrophic.
Amphetamine, and related compounds, are classic examples of performance-enhancing agents. Sleep deprivation studies lasting 60 hours have demonstrated that stimulant drugs, and caffeine to a lesser extent, clearly ameliorate the deficits in performance associated with significant sleep deprivation. This is an issue of great practical importance. For example, soldiers on long range patrols may require stimulants when they need to hastily return to base after completing a mission. Pilots may need stimulants when they are required to fly long missions. It is anticipated that continuous operations will be more likely in the future because technologic advances have made it easier to conduct nighttime operations.
Scenario: Sentry duty, watching a radar screen, listening to sonar and other military tasks that require sustained vigilance. It has been suggested that many critical mistakes occur as a result of boredom rather than excess operator workload. Routine day-to-day operations often require sustained vigilance and, even during wartime, crews can become bored and lose concentration. It was reported in the press that the crews of Patriot missile batteries in Saudi Arabia consumed large quantities of caffeine-containing beverages to maintain alertness when on duty. Simulator studies and laboratory research with caffeine support its utility in situations where vigilance must be maintained. Nutritional stimulants might be helpful when crew members must maintain vigilance for long periods of time.
Scenario: Intense and moderate combat where psychological stress leads to extreme fear and anxiety. Of special interest to the military would be agents that prevent acute combat stress syndrome, previously known as battle fatigue. In intense combat even highly motivated, well trained troops may suffer
significant attrition from this syndrome. Treatments that could prevent it would be invaluable.
Scenario: Impaired performance due to exposure to extreme environmental conditions. Treatments that reduce the adverse effects of environmental extremes on mental performance would be useful. Hypobaric hypoxia readily impairs performance. Soldiers may be rapidly deployed to high altitudes without time for acclimatization. Acetazolamide appears to enhance cognitive performance impaired by acute hypoxia. Temperature extremes can also affect brain function. Tyrosine, because it seems to reduce some of the adverse effects of acute stress, is a nutrient of interest for this application.
Scenario: Cognitive function, memory and judgement are clouded by information overload and stress. Virtually any task that is carried out by a soldier has a memory and cognitive component. They are especially critical at the command level. Although there are no compounds that reliably enhance memory or other higher level cognitive functions, a food constituent that sustains memory when soldiers are exposed to stress would be of great use to the military.
Scenario: In general, the unpredictability of combat means that soldiers may have to sleep whenever they have the opportunity, not necessarily when they are tired or relaxed. In addition, abrupt changes in duty hours are not uncommon. Conventional hypnotics, and also the nutrient tryptophan, have been tested as agents to speed reentrainment to new duty cycles. There are reports that British aircrews used benzodiazepines during the Falklands conflict, so that they could sleep during off-duty hours. Similar agents might be used to prevent jet lag and to speed entrainment to new work schedules. Agents that will assist soldiers to sleep are of great interest, however they must not impair performance, either after the designated sleep period, or if soldiers must be suddenly awakened. The hormone melatonin may be beneficial in such circumstances.
Scenario: Impaired fine motor performance due to acute stress. Snipers, tank gunners, and bombardiers are all required to maintain fine motor control under severely stressful conditions. Beta-adrenergic blockers have reportedly been used to enhance the performance of individuals engaged in a variety of situations including pistol marksmanship competitions, public speaking and concert performances, Presumably, such drugs reduce the peripheral consequences of acute stress, such as tremor, and therefore enhance performance and possibly reduce subjective perception of stress. They also may have direct central effects on higher level functions as well. Specialized units might employ nutrients with such effects; e.g. tank gunners, snipers.