Anabolic and Catabolic in Weight Training

Man weight lifting

Mel Curtis / Getty Images

Anabolic means "building up" and catabolic means "breaking down." Anabolism and catabolism are the two sides of metabolism—building up and breaking down components to maintain the function of the body and the balance of energy stores.


Weight training seeks to maximize anabolic muscle building and minimize loss of muscle through catabolism. When you hear anabolic used in terms such as anabolic state and anabolic steroids, it is referring to the muscle-building processes and the hormones that promote them. Likewise, when you hear the word catabolic, it will mean processes that lead to losing the muscles you work hard to build.

Anabolic metabolism (anabolism) builds new compounds and tissues, including muscles. The body uses building blocks such as proteins and amino acids in this process and burns energy to do it. In weight training, anabolic metabolism builds and strengthens muscles and bones.

Catabolic metabolism (catabolism) breaks down complex compounds and body tissues. This releases energy. The body uses catabolism when a source of energy is needed. Sustained high-intensity exercise, such as running a marathon, can result in the catabolism of muscle as the body needs to break down protein for an energy source.

Exercising hard for a long period of time without replacing energy with food and drink can lead to the breaking down of muscle for fuel.

Impact of Hormones and Steroids

Hormones are produced naturally in the body to regulate metabolism, including the use and storage of energy and building of muscle and other tissue.

Anabolic hormones include growth hormone, IGF1 (insulin growth factor), insulin, testosterone, and estrogen.

Anabolic steroids are natural or synthetic drugs that mimic the effects of testosterone, the male sex hormone. Anabolic steroids are often banned in sports because they are performance-enhancing drugs.

As they are prescription drugs, they are illegal to obtain and use without a medical need. Anabolic steroids have unpleasant and dangerous side effects, which is why they are only available by prescription and require medical supervision.

They are used to build more muscle in a shorter period of time. Some legal dietary supplements, such as DHEA, are building blocks of steroid hormones and might be taken in an attempt to build muscle artificially. Bodybuilders who engage in "natural bodybuilding" don't use prohibited drugs to promote muscle growth.

Catabolic hormones include cortisol, glucagon, adrenaline, and other catecholamines. These hormones may not affect all tissues the same; they can have catabolic effects in making energy available, but not break down muscle.

Muscle Building

Weight trainers want to exercise while in an anabolic state, with enough nutrients in their system to fuel their workout and provide the building blocks of protein for muscle growth. They follow pre-workout nutrition regimens.

During and after workouts they take in food and drink that will provide enough nutrients to maintain the anabolic state. They design workouts to challenge their muscles, so the body responds by building more muscle.

Sleep is another important component of the anabolic state, allowing the body to build and repair muscle more effectively.

Anabolic Product Labeling

You may see nutritional products and supplements labeled as either anabolic or anti-catabolic.

  • Anabolic products provide carbohydrates, proteins, and amino acids that they claim will be absorbed quickly and available to the muscles to build more muscles.
  • Anti-catabolic labels might be put on food and supplements that take longer to digest, so they provide the needed nutrients over a longer period of time.
Was this page helpful?
Article Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute on Drug Abuse. Anabolic Steroids. Revised August 2018.