Intense exercise may unexpectedly contribute to weight gain by reducing physical activity and lowering body temperature due to disruptions in the circadian rhythm of the stress hormone corticosterone. Regular physical activity is crucial for maintaining overall health and is often recommended for weight loss. Engaging in daily exercise, whether intense or light, offers numerous benefits for the body and mind. However, a recent mouse study suggests that intense exercise sessions may lead to decreased subsequent physical activity and lower body temperature, which can impact weight loss efforts. This research highlights the importance of considering not only the calories burned during exercise but also the subsequent activity levels and circadian rhythm when designing effective weight loss programs.
Lead researcher Takashi Matsui, PhD, explained that while exercise is a powerful weight loss strategy, a single session of high-intensity exercise can reduce subsequent physical activity and core body temperature, leading to weight gain despite no changes in food intake. This weight gain may be attributed to disruptions in the circadian rhythm of corticosterone and disturbances in the synchronization between physical activity and body temperature. It is essential to consider both exercise intensity and the body’s natural rhythms when designing effective weight loss regimens.
Health experts not involved in the research, such as senior brain health coach Ryan Glatt and medical director Mark A. Anton, noted the complex effects of high-intensity exercise on metabolism and weight loss. Glatt suggested rethinking the focus on intense exercise and considering the benefits of moderate and consistent activity for weight loss. Anton emphasized the importance of balancing exercise intensity with rest and recovery, along with incorporating a mix of aerobic exercises and resistance training for optimal results.
The study adds new evidence to the theory that animals tend to compensate for energy expenditure from exercise by reducing energy use in other activities, potentially impacting weight management efforts. To fully benefit from exercise, Matsui recommended engaging in moderate exercise regularly without hindering daily activities. This balanced approach helps ensure sustained benefits from exercise without inadvertently leading to weight gain. While the study was conducted on mice, the findings can serve as a reminder to individuals to consider the overall impact of exercise intensity and frequency on weight loss and overall health.
