Inclusion Criteria:  Healthy active duty Soldiers 18-40 years old Available for study duration  Exclusion Criteria:  Failure of an Army Physical Fitness/Combat Test (APFT/ACFT) test On a physical profile that prevents them from 1) engaging in intense aerobic exercise, 2) running on a treadmill, 3) riding the stationary bike, and 4) performing a cognitive task on a computer screen. Medically non-deployable Impaired cognitive function due to medication, injury or illness, Have been advised by a medical professional not to engage in aerobic exercise Are a pregnant female