ABSTRACT The Effects of a Novel Exercise Training Suit on Cardiorespiratory Fitness, Body Composition and Leg Strength Trevor Michael Curry The physiological responses to physical activity or exercise using external load carriage systems (LCS) in the form of weighted personal protective equipment, backpacks, or vests have biomechanical and human performance implications. It remains unclear whether a new unique LCS in the form of a weighted (5.45 kg) full-bodied exercise suit can induce greater improvements in performance and body composition. Twenty-one healthy males (20±3 years; 24.9±3.6 body mass index (BMI); 25.1±6.4% total percentage body fat ( % fat); 120.1±17.3 kg lean mass; 146.2±35.4 kg leg press 1-repetition max; 1.25±0.14 g·cm-2 bone mineral density; 49.5±8.53 mLO2·kg-1·min-1 maximal oxygen consumption (VO2max)) were matched for VO2max and physical characteristics before being randomly allocated into an aerobic exercise intervention with or without the exercise suit using a treadmill at the Cal Poly Recreation Center. Participants jogged at 60%-70% of their maximum heart rate for 30 min three times a week on nonconsecutive days for six weeks. Weight was recorded before and after each session while heart rates, blood pressures, and tympanic membrane temperatures were recorded incrementally during each session. Thereafter, VO2max and the same physical characteristics were measured and used to analyze the changes before and after the 6-week program. The results indicate that there was no difference for the change in any of the variables measured during and between the exercise intervention. Future studies examining the effect of the exercise suit on these variables should strongly consider larger sample sizes and other subpopulations to gain the statistical power to measure the effects of the exercise suit.