Bodybuilding supplements

What are bodybuilding supplements ?

Bodybuilding supplements are dietary supplements often used for the purpose of increasing lean body mass. Besides looking to  increase muscle, these supplements are consumed to increase body weight, improve athletic performance, and in some cases decrease the percentage of body fat.

Among the most widely used are:

  • Protein 
  • Creatine
  • Branched-chain amino acids (BCAA)
  • Glutamine
  • Arginine
  • Essential fatty acids
  • HMB
  • ZMA[1] 
  • Weight loss products 

These supplements can be found  either as single ingredient preparations or in the form  of proprietary blends. Proprietary blends aim to offer synergistic advantages.


Bodybuilders often supplement their diets with protein because of convenience, ease of preparation, and to avoid overconsumption of carbohydrates and fats. 

Bodybuilders might require higher-than-average quantities of protein to support the muscle growth goals unique training requirements. [1]

One study concluded that athletes consuming a  total protein intake of up to 1.6 g/kg of body weight per day for a period of 13 weeks, experienced an increase in strength and fat-free mass. Higher intakes would not further contribute.[2 ]

Protein supplements are sold in ready-to-drink shakes, bars, bites, oats and powders. Protein powders are the most popular and may have added flavors.

The two main types of protein powder are whey protein and casein protein.

Whey protein

Whey protein contains high levels of all the essential amino acids and branched-chain amino acids, it also has the highest content of cysteine. Whey protein provides amino acids used to aid in muscle recovery.[3 ] [4 ]

Whey protein is derived from the process of making cheese from milk. 

There are three types of whey protein: 

  • Whey concentrate–  contains  29–89% protein by weight
  • Whey isolate– contains 90%+ protein by weight
  • Whey hydrolysate– It is enzymatically predigested and has the highest rate of digestion of all protein types

Casein protein 

Casein protein or  milk protein has glutamine, and casomorphin.

The casein molecule has the  ability to form a gel or clot in the stomach. This clot is able to provide a sustained slow release of amino acids into the bloodstream, it can  sometimes last for several hours.[5

BCAAs – Branched-chain amino acids

BCAAs can be ingested before exercising and used as energy during the training

BCAA supplements can help to decrease levels of lactic acid and reduce the temporary sensation of pain in the muscles.[6]

Recent studies have also shown that BCAAs reduce the levels of circulating free fatty-acids (FFA) in the blood. This reduction can help to reduce the sensation of fatigue as a result of exertion.[7]

BCAA supplementation can also help to decrease the levels of creatine kinase in muscle cells post exercise. Creatine kinase is an indicator of muscle damage.[8


Creatine is  a naturally occurring organic acid in our bodies, it supplies energy to muscle cells for short bursts of energy. Creatine can be found naturally in many common foods such as herring, tuna, salmon, and beef.

Several scientific studies have shown that creatine can improve strength,[9] muscle mass,recovery times and energy,[10] . 

Recent studies have also shown that creatine improves brain function.[11] and reduces mental fatigue.[12

Creatine can be purchased in different forms,  creatine monohydrate and creatine ethyl ester are the most popular.

In The New Encyclopedia of Modern Bodybuilding, Creatine monohydrate is mentioned as the most cost-effective dietary supplement in terms of muscle size and strength gains.[13]

Consuming creatine  with protein and carbohydrates can have a greater effect than either  creatine, protein or carbohydrates alone.[14]

β-Hydroxy β-methylbutyrate – HMB

HMB has been shown to augment gains in muscle size [15], muscle strength,[17] and lean body mass[18]. It can also reduce exercise-induced skeletal muscle damage,[19]and aid in recovery from high-intensity exercise.

HMB produces these effects by increasing muscle protein synthesis and decreasing muscle protein breakdown[20]

The greatest reduction in muscle damage from exercise happens when calcium HMB is ingested 1–2 hours prior to exercise.[21]


Prohormones are precursors to hormones , they are often  sold as a precursor to the natural hormone testosterone. They were initially available over the counter; they were made illegal without a prescription in the US in 2004. Their use is prohibited by most sporting bodies.

MRPs- Meal replacement products 

Meal replacement products (MRPs) are pre-packaged powdered drink mixes or edible bars designed to replace prepared meals. MRPs are often high in protein, low in fat, and  have a low to moderate amount of carbohydrates. They also contain different vitamins and minerals.

Most MRPs use whey protein, casein, soy protein and egg albumin as protein sources. The Carbohydrates are often obtained from maltodextrin, oat fiber, brown rice, and wheat flour. Some MRPs also contain flax oil powder as a source of essential fatty acids.

MRPs can also contain other ingredients, such as creatine monohydrate, glutamine peptides, L-glutamine, calcium alpha-ketoglutarate, additional amino acids, lactoferrin, conjugated linoleic acid, and medium-chain triglycerides.

There are also MRPs known as “weight gainers”, which are products with a higher carbohydrate to protein ratio. 

Thermogenic products

A thermogenic is a supplement that claims to cause thermogenesis. Thermogenisis will result in  an increased body temperature, increased metabolic rate, and an increased rate in the burning of body fat and weight loss. Until 2004 almost every product in this category contained ephedrine. On February 6, 2004 the Food and Drug Administration (FDA) banned the sale of ephedra and ephedrine for use in weight loss formulas. Several manufacturers replaced the ephedra with bitter orange or citrus aurantium (containing synephrine) instead of the ephedrine.

Possible side effects and precautions 

Many of the benefits claimed by these supplements are  based on scientifically proven studies. However, because of marketing purposes, the terms used to describe the benefits may change considerably from the scientific studies.

Sometimes ingredients listed have been found to be different from the contents. In 2015, Consumer Reports reported unsafe levels of arsenic, cadmium, lead and mercury in several of the protein powders that were tested.[22 ]

In the United States, the manufacturers of dietary supplements don’t need to provide evidence of product safety prior to marketing to the Food and Drug Administration (FDA)[23].  

In 2013, one-third of the supplements tested were adulterated with unlisted steroids.[24

Health problems

The US FDA reports 50,000 health problems a year due to dietary supplements  and these often involve bodybuilding supplements.[25

Liver damage

Catechins from green tea, anabolic steroids, and the herbal extract aegeline are ingredients attributed to liver injuries .[26 ]

Lack of effectiveness

Besides being potentially harmful, some studies have argued that there is little evidence to indicate any benefit in some bodybuilding supplements.[27]