Going high to keep body mass low: how post-exercise exposure to high altitude influences calories in and calories out

Introduction: Maintaining body mass requires a balance between energy intake and energy expenditure. Examined globally, 2 billion people are overweight or obese, demonstrating a system that is off balance. Weight loss of even modest proportions in overweight/obese individuals improves blood glucose, lowers cholesterol, and reduces blood pressure. However, particularly for those in the weight-reduced state, hunger levels are difficult to suppress, and efforts to increase exercise are met with resistance. One approach to promoting body mass regulation may be to elevate caloric expenditure for a given exercise session. Because high altitude upregulates metabolic rate and lowers appetite, one method of increasing expenditure and lowering intake may be to combine exercise with high altitude exposure. Methods: Fourteen participants will run for 30 minutes at sea level, followed by a 30 min recovery period. Throughout this recovery period participants will breathe a) air equivalent to recovering at sea level, or b) air at a simulated high altitude (~14,000 ft). Caloric expenditure will be calculated via collection of inspired and expired gases, and plasma samples will be used to determine the influence of high altitude recovery on the appetite suppressing hormone, leptin. Results: To date, three people have completed the study. Preliminary data show an increase in caloric expenditure when recovering from exercise in an environment simulating high altitude. Conclusions: Initial results suggest that recovering from exercise at a simulated high altitude delays recovery for a given exercise session, thereby promoting increased caloric expenditure and, subsequently, a healthy body mass regulation