From a change in brain biochemistry to an increase in self-confidence, regular exercise impacts the mind as much as the body. Here are four ways your workouts reduce stress and improve your mood.

Happiness hormones

Serotonin is a neurotransmitter that improves mood, and its function is increased when you exercise. Physical activity also stimulates the release of endorphins, hormones that reduce feelings of pain and increase feelings of pleasure. Due to its power to increase these pleasure hormones, regular exercise is considered an effective treatment for mild to moderate depression.

Improved sleep

According to sleep medicine expert Dr. Virgil Wooten, 20-30 minutes of aerobic exercise will increase your body temperature for 4 to 5 hours, but it will then drop to a lower level than if you hadn’t exercised. This drop in temperature promotes restful sleep, which can improve your mood and reduce stress.

Alone time

With so much emphasis placed on the necessity of a workout partner for motivation, the benefits of exercising alone are often overlooked. Taking a break from conversation allows you to reflect and organize your thoughts. A quiet workout reduces stress and leaves you feeling mentally refreshed.

Sense of accomplishment

Finishing a 10K or completing an exercise class improves your self-esteem and gives you a more positive outlook. Your sense of accomplishment increases self-efficacy, which is the belief in your ability to accomplish a task. As your self-esteem and self-efficacy build, your positive view of exercise, and the motivation to stick with it, will improve.

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.