Creatine monohydrate remains one of the few nutritional supplements where research has consistently shown ergogenic benefits. Given all the known benefits and favorable safety profile of creatine supplementation reported in the scientific and medical literature, it is widely viewed that it is more a case of why wouldn’t it be taken as a supplement than the contrary.
Creatine is a substance that is found naturally in human muscle cells. Creatine helps one’s muscles to produce energy both pre-workout and during high-intensity exercise. Studies consistently show that creatine supplementation increases intramuscular creatine concentrations which may help explain the improvements in high-intensity exercise performance that leads to greater training adaptations. In addition to athletic and exercise improvement, research shows that creatine supplementation may enhance post-exercise recovery, injury prevention, thermoregulation, rehabilitation, and concussion. These studies provide a large body of evidence that creatine can not only improve exercise performance, but can play a role in preventing and/or reducing the severity of the injury, enhancing rehabilitation from injuries, and helping athletes tolerate heavy training loads.
The Role of Creatine:
Creatine is a naturally occurring non-protein amino acid compound usually found in red meat and seafood. The majority of creatine is found in skeletal muscle and small amounts are also found in the brain and testes. About two-thirds of intramuscular creatine is phosphocreatine (PCr) with the remaining being free creatine. The total creatine pool (PCr + Cr) in the muscle averages about 120 mmol/kg of dry muscle mass for a human weighing 70kg. However, the upper limit of creatine storage appears to be about 160 mmol/kg of dry muscle mass in most humans. About 1–2% of intramuscular creatine is broken down into creatinine ( its metabolic byproduct) and excreted in the urine. Therefore, the body needs to replenish about 1–3 g of creatine per day to maintain normal creatine stores depending on the muscle mass of the human. About half of the daily need for creatine is obtained from the diet. Eg, a pound of uncooked beef and salmon provides about 1–2 g of creatine. The remaining amount of creatine is synthesised primarily in the liver and kidneys from arginine and glycine by the enzyme arginine.
The most commonly studied form of creatine is creatine monohydrate. The intake of creatine involves the absorption of creatine into the blood and then uptake by the target tissue. The best levels of creatine absorption, typically peak at about 60 min after oral ingestion of creatine monohydrate. An initial rise in plasma creatine levels, followed by a reduction in plasma levels can be used to indirectly suggest increased uptake into the target tissue. However, the gold standards for measuring the effects of creatine supplementation on target tissues are through magnetic resonance spectroscopy (MRS), muscle biopsy, stable isotope tracer studies, and/or whole-body creatine retention assessed by measuring the difference between creatine intake and urinary excretion of creatine.
Benefits of Creatine:
A large body of evidence now indicates that creatine supplementation increases muscle availability of creatine and PCR and can therefore enhance acute exercise capacity and training adaptations in adolescents, younger adults, and older individuals. These adaptations would allow an athlete to do more work over a series of sets or reps leading to greater gains in strength, muscle mass, and/or performance due to an improvement in the quality of training. Creatine supplementation has primarily been recommended as an ergogenic aid for power/strength athletes to help them optimise training adaptations.
Creatine is found in high amounts in and therefore its use is not banned by any sports organisation although some organisations prohibit the provision of some types of dietary supplements to athletes by their teams. In these instances, athletes can purchase and use creatine on their own without penalty or violation of their banned substance restrictions.
Is Creatine Safe?
Since creatine monohydrate became a popular dietary supplement in the early 1990s, over 1,000 studies have been conducted and billions of servings of creatine have been consumed. The only consistently reported side effect from creatine supplementation has been weight gain.
The following are just some of the views of the International Society of Sports Nutrition in terms of creatine supplementation as the official position of the Society:
- Creatine monohydrate is the most effective ergogenic nutritional supplement currently available to athletes with the intent of increasing high-intensity exercise capacity and lean body mass during training.
- Creatine monohydrate supplementation is not only safe but has been reported to have a number of therapeutic benefits in healthy and diseased populations ranging from infants to the elderly. There is no compelling scientific evidence that the short- or long-term use of creatine monohydrate (up to 30 g/day for 5 years) has any detrimental effects on otherwise healthy individuals.
- Label advisories on creatine products that caution against usage by those under 18 years old, while perhaps intended to insulate their manufacturers from legal liability, are likely unnecessary given the science supporting creatine’s safety, including in children and adolescents.
- At present, creatine monohydrate is the most extensively studied and clinically effective form of creatine for use in nutritional supplements in terms of muscle uptake and ability to increase high-intensity exercise capacity.
- The addition of carbohydrate or carbohydrate and protein to a creatine supplement appears to increase muscular uptake of creatine, although the effect on performance measures may not be greater than using creatine monohydrate alone.