The Best Legal Muscle Building Supplements

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The most effective "supplements" used to build muscle by bodybuilders and athletes are synthetic hormones, also known as anabolic steroids. However, there are also legal supplements that can be effective in building muscle when used correctly. If you're looking to supplement your muscle growth legally, familiarize yourself with the following options.


Protein is perhaps the most common and widely accepted legal muscle building supplement. Supplemental protein is often delivered in the form of powder, and generally falls into one of three categories: whey protein, casein protein or soy protein. Whey protein boasts the most comprehensive amino acid content, and is thus the most popular variety. These amino acids form the building blocks for new muscle tissue. As such, protein supplements are often used in lieu of or in addition to protein rich diet programs. A 2007 study published in the journal of "Medicine & Science in Sports & Exercise" found that whey protein supplementation resulted in significant gains in both muscular strength and hypertrophy over time.


Creatine is another popular supplement for bodybuilding and athletic performance, and is cited by Arnold Schwarzenegger in The New Encyclopedia of Modern Bodybuilding as the most cost effective muscle building supplement. It is generally sold as a monohydrate powder, and is often consumed in combination with simple carbohydrates. Creatine is a naturally occurring body acid, also found in red meats, and is primarily used to facilitate the supply of energy to muscle cells. It plays crucial role in bursts of anaerobic energy, such as those involved in weight lifting. It functions by drawing water into individual muscle cells, increasing their size and potential strength. A 1999 study published in the journal "Medicine & Science" in Sports & Supplementation found that creatine supplementation had a significant positive impact on muscular strength and body composition.

Nitric Oxide

Nitric oxide supplements are popular as a pre-workout means of increasing of increasing the efficacy of your training. Nitric oxide is generally consumed in combination with simple carbohydrates and other ingredients. Biologically speaking, it is an important regulator of various processes in the immune, nervous and cardiovascular systems. In its muscle building application, it functions as a vasodilator, expanding your blood vessels to allow more oxygenated blood to reach your muscles. This allows your muscles to perform at a higher level of strength and endurance over the course of your workout, creating greater stimulation for the development of new muscle fibers.