Nighttime eating is often associated with metabolic syndrome and poor body composition and these conditions may be influenced by the natural decline in metabolism that occurs during sleep. However, previous research indicates that protein consumption increases metabolic rate more than carbohydrates or fat, and therefore may attenuate this decline when consumed at night before bed. In addition, digestion and absorption kinetics of whey protein (WP) and casein protein (CP) may independently influence appetite and body composition. Therefore, altering the type of protein or macronutrient consumed late at night when starting an exercise training program may influence changes in resting metabolic rate (RMR), appetite (hunger, desire to eat, and satiety), and body composition. The purpose of this study was to compare the effects of isocaloric maltodextrin (PLA), WP and CP supplements when consumed immediately prior to nocturnal sleep when combined with four weeks of exercise training on RMR, appetite, and body composition.