how does exercise reduce stress?

Exercise helps to reduce stress through multiple physiological mechanisms. According to Andrew Huberman, one significant way it does this involves the post-exercise stress response. Essentially, physical activity leads to an increase in certain substances like cortisol and various immune cells, which are part of the body's natural response to stress.

Post-exercise, the body can experience heightened levels of inflammation. However, consuming carbohydrates after exercising can help mitigate this inflammation by approximately 30% to 40% compared to just drinking water. This reduction in inflammation not only helps in managing and reducing the body's stress response but also aids in improving the function of the immune system, which can otherwise be compromised by chronic stress 1.

Exercise reduces stress through several additional mechanisms beyond the initial release and regulation of stress markers post-exercise.

1. Physiological Sigh: Andrew Huberman describes a specific breathing technique known as the physiological sigh, which is used to rapidly reduce stress. This pattern of breathing involves a double inhale followed by an extended exhale, efficiently offloading carbon dioxide. This process helps to reduce stress very quickly and can be used in real-time during stressful situations. It is particularly effective because it reinstates the normal function of air sacs in the lungs, which can deflate under stress, impeding optimal gas exchange 1.

2. Emphasis on Exhales: Stress reduction is also facilitated by breathing techniques that emphasize exhales. During exhales, the heart rate slows down due to the decrease in thoracic cavity space, which affects blood flow and heart size. This physiological response is a direct and quick way to calm the nervous system and reduce stress 1.

3. Cyclic Sighing: Cyclic sighing, involving a repeated pattern of a double inhale through the nose and a long exhale, has been found to reduce stress not just during the activity but throughout the day. This practice has been shown to improve mood and sleep quality, making it a robust method for ongoing stress management 2.

These mechanisms highlight how both physical activity and associated breathing practices can be powerful tools in managing and reducing stress, with immediate and lasting effects.