How High-Intensity Exercise Affects Growth Hormone Levels

One of the benefits of exercise is the effect it has on levels of human growth hormone. Growth hormone is a hormone produced by the pituitary gland in the brain and plays a critical role in growth during childhood, but its importance doesn’t stop there. Growth hormone also has positive health benefits for adults by helping to build lean body mass and stronger bones. It also plays a role in fat-burning. Fat cells have receptors for growth hormone on their surface. When growth hormone binds to these receptors, it stimulates the breakdown of fat and blocks its synthesis. Unfortunately, growth hormone levels begin to decline after the age of 30, a factor that’s partially responsible for the increase in body fat and loss of muscle mass people experience as they age. The good news is exercise boosts growth hormone levels naturally and that has favorable effects on body composition – but you need more than a walk in the park to increase growth hormone levels.

 What Type of Exercise Boosts Growth Hormone Levels?

According to research published in the Journal of Clinical Endocrinology and Metabolism, growth hormone levels rise significantly only with high-intensity exercise that taps into the anaerobic energy system. It also has to be of a certain duration. In this study, a minimum of 10 minutes of high-intensity exercise was needed to increase growth hormone levels. Low-intensity exercise had no effect on growth hormone.

High-intensity interval training works well for boosting growth hormone levels because it allows you to work hard for short periods of time without becoming fatigued to the point you have to stop. High-intensity workouts are the most effective for producing an after-burn, the state where you continue to burn calories even after you stop exercising. Long sessions of moderate-intensity exercise don’t give you the same after-burn.

Exercise isn’t the only factor that affects growth hormone levels. To get the full benefits of the growth hormone your body naturally produces, don’t skimp on sleep. Growth hormone is released in the greatest quantity during deep sleep, and not getting adequate sleep will blunt the amount of growth hormone your body is exposed to. That’s one reason lack of sleep contributes to weight gain.

 The Bottom Line?

When it comes to increasing growth hormone levels and burning fat, high-intensity exercise will give you a greater boost than moderate-intensity cardio sessions. If you haven’t tried high-intensity interval training, you’re missing out on a way to add variety to your workout and get leaner at the same time. It’s also a good way to break out of a weight loss plateau and reduce boredom. Give it a try.

References:

J. Clin. Endocrinol. Metab. 1992 Ju; 75(1): 157-62.

J Clin Endocrinol Metab. 2000 Feb;85(2):799-803.

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