THE ROLE OF PREFRONTAL CORTEX HEMODYNAMICS, INHIBITORY CONTROL AND BODY FAT IN EXERCISE TOLERANCE
Brain, Cognition, Sedentary Lifestyle, Fatigue and Obesity.
Physical inactivity is associated with a myriad of negative physical, psychological, and cognitive effects. For instance, physical inactivity appears to compromise inhibitory control, reduce exercise tolerance, and facilitate weight gain. However, the mechanisms through which physical inactivity may impact the cognitive and physiological functioning of the organism remain unclear. One hypothesis is that long periods of physical inactivity could impair the function of the prefrontal cortex (PFC), impairing one’s ability to inhibit default behaviors and, therefore, reduce exercise tolerance. Two studies were conducted with the objectives of (1) understand the relationship among PFC hemodynamics, inhibitory control, and exercise tolerance in sedentary individuals who are overweight or obese and (2) verified whether the cost-efficiency of PFC function and cognitive inhibitory control can mediate the relationship between body fat and exercise tolerance. In study 1, our results indicate that endurance performance varied with PFC oxygenation. We also found that inhibitory control played a key role in mediating the relationship between PFC oxygenation and exercise performance, suggesting that the ability to inhibit has an impact on exercise behavior. We argue that psychophysiological mechanisms underlying the relationship between cerebral hemodynamics and exercise tolerance in overweight or obese individuals may be driven, in part, by inhibitory control. While in study 2, suggest that better PFC cost-efficiency and inhibitory control may contribute to the regulation of exercise tolerance in sedentary and overweight individuals. Thus, these studies bring an additional understanding between the body-mind-brain interaction during physical exercise, and this fact may be important to understand the contingencies of sedentary behavior and exercise intolerance.