Creatine is a compound that is made naturally in the body to supply energy. It is produced in the liver from the amino acids - glycine, arginine and methionine. From the liver, it is transported in the blood to the muscle cells. The muscle cells turn over about 2-3g of creatine per day. Creatine can be obtained in the diet from fish, beef, and pork, therefore vegans and vegetarians struggle to obtain creatine from the diet. The average sized person stores about 120g of creatine. This is mainly stored in the skeletal muscles.
What does it do?
Creatine combines with phosphorus to form phosphocreatine (PCr) in your muscle cells. This energy rich compound fuels your muscles during high intensity activities such as weight lifting and sprinting. Taking creatine supplements can increase PCr levels by up to 2%. Creatine helps to reduce muscle protein breakdown following an intense exercise which can result in greater strength and recover faster between sets and therefore improved ability to continue doing repeated sets. There are many studies that show creatine is an effective aid for increasing strength and muscles mass and enhancing performance in high intensity activities.
The International Society of Sports Nutrition (ISSN) describes creatine as ‘the most effective ergogenic nutritional supplements currently available to athletes in terms of increasing high density exercise capacity and lean body mass during training’.
Do I need it?
If you lift weights or do a high intensity sport like sprinting, rugby or football, creatine supplements may help increase your performance, strength and muscle mass. For some people, their muscle creatine concentration increases only very slightly. This is due to the difference in muscle fibre types. Fast twitch (FT) fibres tend to build higher concentrations of creatine than slow twitch (ST) fibres. Athletes with naturally low FT fibres may experience less gains from creatine supplements, however, taking creatine with a carbohydrate source, raises insulin and therefore helps creatine uptake by muscle cells.
How much creatine should I take?
The most common creatine loading protocol is 4 x 5-7g doses per day over 5 days. This
protocol can work but it definitely doesn't mean it is the best way to load up because
you are more likely to have some side effects of water retention. The key to using
creatine supplementation effectively is to take it in small quantities at a time. That way
the creatine consumed goes into the muscle cells and not in your urine. Scientists
recommend taking creatine with or shortly after a meal. This means the post meal will
increase insulin to get more creatine into the muscle cells. Adding creatine to the post
exercise meal will help to boost muscle creatine levels. Check back next week for more information on how to supplement with creatine.
What is the best form of creatine?
Creatine monohydrate is the most common and widely available form of creatine. It is a
white powder that is dissolvable in water and has no taste. It is the most concentrated
form and the least expensive. It is made up of a molecule of creatine with a molecule of
water attached to it. There are other forms of creatine (creatine citrate, creatine serum),
but there is very little evidence to suggest they are better absorbed or can increase
performance or muscle mass.
Are there any side effects to taking creatine?
Creatine seems to be safe both short term and long term, there are side effects of
weight gain mainly due to the extra water in the muscle cells.
References
Gualano B, Roschel H, Lancha AH Jr, Brightbill CE, Rawson ES. In sickness and in
health: the widespread application of creatine supplementation. Amino Acids. 2012
Aug;43(2):519-29.
Bean, A,. 2017, Complete Guide to Sports Nutrition. [S.I]: Bloomsbury Sport
Jäger R, Purpura M, Shao A, Inoue T, Kreider RB. Analysis of the efficacy, safety, and
regulatory status of novel forms of creatine. Amino Acids. 2011 May;40(5):1369-83.
Kreider, R.B., Kalman, D.S., Antonio, J. et al. International Society of Sports Nutrition
position stand: safety and efficacy of creatine supplementation in exercise, sport, and
medicine. J Int Soc Sports Nutr 14, 18 (2017).
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