Creatine is a natural occurring substance that helps supply energy to muscles. Half of stored creatine comes from food, mainly fresh meat, so as a vegetarian I am likely to have lower levels of muscle creatine.  The enzyme creatine kinase (CK) is responsible for the reversible reaction whereby creatine is converted along with ATP to create phosphocreatine and ADP to generate energy.

Whilst creatine has been shown to be beneficial for short high intensity exercises such as weight lifting, it has not shown to have any benefit to endurance activity performance. In fact as creatine is also responsible for weight gain of around 1kg when taking the ‘loading dose’ of 20g a day it may even slow an endurance athlete down without providing any benefit to performance. A study has however, looked at the benefits of creatine on muscle recovery following endurance running

In the study published in Life Sciences journal, subjects were given 4 doses a day of 5g of creatine and 15g of maltodextrine, while the control group received just maltodextrine for 5 days, before a 30km race. The runners were experienced marathon runners with personal best (PB) times of 2.5 -3 hours.

Blood CK levels can be raised from damage of the muscle tissue as a result of intense training and it is often used as a marker of muscle injury. In this study by the University of São Paulo, it was found that athletes from the control group had increased CK levels suggesting a high level of cell injury and inflammation while Creatine supplementation reduced these increases.

In short term studies of less than two weeks there have not been reported side effects of taking creatine supplements. Dr Santos, the papers author reported that ‘the runners finished in times equivalent to their PB, without any side effects such as cramping, dehydration or diarrhoea whilst taking the supplements or during the race.’ However athletes who have taken it long term have reported muscle cramping and kidney damage.

In 2007 International Society of Sports Nutrition published its position on the use of creatine supplementation and exercise. Amongst some of their statements they concluded that ‘there is no scientific evidence that the short- or long-term use of creatine monohydrate has any detrimental effects on otherwise healthy individuals. Creatine monohydrate supplementation is not only safe, but possibly beneficial in regard to preventing injury and/or management of select medical conditions when taken within recommended guidelines.’

Recovering from endurance exercise is important for the long distance runner, but is it worth taking creatine supplements in the days leading up to a marathon to prevent damage and aid recovery. Is it worth possible muscle cramps and other side effects during the race after all you don’t know how your individual body will react?

What’s your view? Are you an endurance athlete who has tried creatine supplements, or do you think we shouldn’t use any type of ergogenic aids? Let us know you experiences or opinions.

Also read related post Can creatine supplements enhance muscle recovery?