Vo2 max, respiratory exchange rate, heart rate, total ventilation and gross atmosphere are monitored during a citrulline malate supplement study conducted by the Air Force Research Laboratory at Brooks City-Base, Texas. Citrulline malate has shown to increase lactate threshold and VO2 max in healthy humans and is being investigated, along with other nutritional supplements and training aids, by AFRL to improve cognitive and physical performance of battlefield Airmen. (Air Force photo by Steve Thurow)