Extreme Exercise and Energy Expenditure (4E) Study

Detailed Summary

The goal of this clinical trial is to provide evidence, through an extreme exercise prescription (1,144 km of road cycling on seven consecutive days), that weight loss is not the appropriate outcome to evaluate the effects of exercise on abdominal adiposity and ectopic fat depots (e.g. liver fat and epi/pericardial fat) in eleven recreational middle-aged male cyclists (aged 50 to 66 years) without symptoms of cardiovascular disease. The main questions it aims to answer are: * If energy intake is substantially increased to compensate energy expenditure and prevent weight loss following an extreme exercise prescription, will significant changes in body composition and body fat distribution be observed? * Will these changes translate into improvements in the cardiometabolic health profile even in the absence of weight loss? Participants will be asked to partake in several evaluations: fasting plasma lipoprotein-lipid profile and inflammation markers, glycated hemoglobin, cardiorespiratory fitness, submaximal exercise test including measurement of energy expenditure, resting and exercise blood pressure and heart rate, evaluation of regional adiposity, liver fat content, epi/pericardial fat, nutritional quality, and level of physical activity. After baseline evaluations, participants will be asked to alternately bike 208 km and 104 km per day on a pre-specified course for seven consecutive days. They will be accompanied during each of the seven bike rides by research professionals in a recreational vehicle. Participants' weight, body composition and waist circumference will be measured under standardized conditions in the morning after an overnight fast and after the exercise. Their heart rate will be continuously monitored, and participants will wear accelerometers to estimate their daily exercise-related energy expenditure. Foods and fluids will be provided to participants and recorded. At the end of the 1,144 km/ 7-days bike ride, baseline evaluations will be repeated with the exception of the maximal exercise treadmill test, nutritional quality, and level of physical activity. To facilitate the conduct of the protocol, the eleven participants will be evaluated and followed in two distinct groups.

Study Details

Timeline

Interventions