Legal steroids refer to workout supplements that may increase muscle mass and athletic performance. However, they are not the same as anabolic steroids. Anabolic steroids are illegal without a prescription.

Anabolic steroids are prescription-only medications for treating certain health conditions. However, people sometimes misuse anabolic steroids to increase muscle mass and athletic performance.

This article discusses what legal steroids are and whether they work. We also outline alternative options for people wishing to improve their fitness.

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Legal steroids are workout supplements that may help increase muscle mass and enhance athletic performance.

Workout supplements typically contain a range of active ingredients, such as:

  • Protein: Molecules containing amino acids, which support muscle growth.
  • Branched-chain amino acids: Amino acids can boost the body’s production of protein.
  • Beta-alanine: A precursor to carnosine, which supports the muscles during intense exercise.
  • Creatine: A substance that exists naturally in muscle cells, which can increase muscle mass and improve physical performance.
  • Caffeine: A stimulant that can increase athletic performance.

Different supplement brands contain a varied combination of the above ingredients. However, the exact amounts of each ingredient are not always clear as companies are not open about their formulas.

Legal steroids are not the same as anabolic steroids. The latter is a synthetic form of testosterone that doctors may prescribe to treat certain hormonal or muscle-wasting conditions. People sometimes misuse anabolic steroids to increase muscle mass and boost athletic performance. However, these drugs may have harmful side effects and are illegal without a prescription.

Below we explore the effectiveness of workout supplement ingredients and supplement blends.

Effectiveness of individual ingredients

Some evidence suggests certain individual ingredients in workout supplements can improve muscle-building and physical performance.

A 2018 meta-analysis in the British Journal of Sports Medicine found that using protein supplements alongside resistance exercise training could increase muscle size and strength.

Creatine is another common ingredient in workout supplements. The International Society of Sports Nutrition suggest it is one of the most effective ergogenic supplements for muscle growth and performance. Ergogenic supplements are substances that enhance the body’s ability to produce energy.

Another ergogenic workout ingredient is caffeine. According to an older review from 2008, even a modest amount of this stimulant equating to around 3 milligrams per kilogram of body weight appears to provide performance-enhancing benefits.

Effectiveness of supplement blends

A 2012 study investigated the effects of a particular workout supplement blend containing the following ingredients:

Over 3 weeks, one group of participants took the supplement before exercise, while the other group took a placebo. Those taking the supplement showed a significant improvement in their lower body muscular endurance. They also reported increased energy levels and reduced fatigue.

A 2018 review in the Journal of the International Society of Sports Nutrition suggests that some multi-ingredient supplements can improve muscle performance.

However, the reviewers note that these products are difficult to study and compare as companies are protective of their individual ingredient blends.

Most multi-ingredient workout supplements are generally safe and have a low risk of major side effects.

However, few studies examine the long-term effects of these products. As such, it is not clear whether using them for extended periods increases the risk of adverse effects or disease.

Some possible risks and side effects of workout supplements are below.

Unsafe ingredients

Some workout supplement ingredients are known to be unsafe. For example, certain products contain a type of amphetamine called 1,3-dimethylamylamine (DMAA). The Food and Drug Administration (FDA) warn that DMAA can increase blood pressure and is unsafe for consumption.

Supplement manufacturers also often do not disclose comprehensive information regarding their products’ ingredients. Therefore, people should use them with caution.


There is a risk that people will become reliant on workout supplements. They may overlook the importance of their exercise habits and nutrition, expecting supplements to make up the difference. This could lead to adverse outcomes.

Workout supplements are not the only option for improving muscle and fitness. Alternatives include:

  • following a consistent exercise routine
  • including compound movement exercises, such as squats and bench presses
  • resting sufficiently between workouts
  • training with enough intensity and gradually increasing resistance over time
  • setting achievable goals with realistic timelines
  • eating a healthful and balanced diet with sufficient protein
  • getting enough sleep

Building muscle and fitness takes time, patience, and motivation. People may benefit from working out with a friend or hiring a personal trainer to help them reach their goals. A variety of fitness apps can also provide guidance and support for healthful exercise habits.

Anabolic steroids can enhance muscle mass and athletic performance. However, they are illegal without a prescription. They can also have harmful side effects, including:

Some people may become addicted to anabolic steroids. They may rely on them for enhanced performance and experience withdrawal symptoms when they stop taking them.

Possible withdrawal symptoms include:

Legal steroids typically refer to multi-ingredient supplements to enhance muscle strength and fitness. Research suggests they may be effective when combined with an appropriate fitness routine.

Generally, blended supplements appear safe, with a low risk of major side effects. However, there are limited studies investigating the long-term effects.

People who take workout supplements should not ignore the importance of a balanced diet and a consistent exercise routine. A personal trainer or fitness app could provide them with the support and motivation they need to reach their fitness goals.