Creatine

According to the International Society of Sports Nutrition (ISSN), creatine monohydrate is the most effective ergogenic nutritional supplement currently available to athletes interms of increasing high-intensity exercise capacity and lean body mass during training (1).

The European Food Safety Authority (EFSA) concluded that a cause an effect relationship has been established between the consumption of creatine, in combination with resistance training, and improvement in muscle strength. In order to obtain the claimed effect, 3 g of creatine should be consumed daily in conjunction with resistance training which allows an increase in the workload overtime. Resistance training should be performed at least three times per week for several weeks, at an intensity of at least 65-75% of one repetition maximum (2).

In its Natural Health Product Monograph, Health Canada has determined that consumption of creatine monohydrate increases lean muscle mass/size when used in conjunction with a resistance training program (3).

Several investigations show the benefit of creatine in muscle development. In a study of 19 healthy female volunteers, researchers found that supplementation with creatine (2.5 g twice/day for 10 weeks) in combination with resistance training significantly increased fat-free mass compared with resistance training only. Additionally, the amount of 1 repetition maximum increments for various exercises was increased by approximately 25% in volunteers given creatine compared to placebo over a 10-week training period (4).

EFSA concluded that a cause and effect relationship has been established between the consumption of creatine and an increase in physical performance during short-term, high intensity, repeated exercise bouts. EFSA concluded that in order to obtain the claimed effect, 3 g of creatine should be consumed daily by adults performinghigh-intensity exercise (1).

Health Canada has permitted the following claim regarding creatine supplementation and fitness performance:

•Improves strength/power/performance in repetitive bouts of brief, highly-intense physical activity (e.g. sprints, jumping, resistance training) (by increasing [muscle/intramuscular] [creatine/phosphocreatine/energy] levels).

Researchers investigating creatine’sathletic benefitsfound that supplementation of 25 g/d for 1 week followed by a maintenancedose 5 g/day increasedbench press and squatperformanceover 12 weeks by 24% and 32%, respectively. Additionally,during weeks 5-8,the average volumelifted in the bench press was expressivelygreater in subjects given creatine than placebo(2).

Animal products such as beef, fish and poultry are rich sources of protein but are absent in vegan diets and may be limited in vegetarian diets (some vegetarians may eat fish). This results in reduced muscle creatine storesin vegan and vegetarian diets. Blancquaert et al. found that the body creatine pool declined over the course of a 3-month vegetarian diet in omnivorous women. When supplementation with creatine was administered, the change was ameliorated. Research has shown that creatine supplementation might be of highest benefit for athletes with low pre-existing muscle creatine stores (1,2).