In research terms, creatine remains the supplement of the moment. Scarcely a week goes by without one or more learned journals reporting on its actual or potential benefits, particularly for sports using explosive power. Much of the research has been carried out on physically active subjects, but there has been relatively little information about the effects of supplementation on highly trained athletes.

Now a group of Norwegian researchers have moved to correct the balance with a study of 18 well-trained male sprinters at local competition level, whose performances were observed to improve significantly after five days of supplementation with high dose creatine.
During the previous two years a substantial part of these athletes' training had consisted of a series of maximal sprints with short rest periods to improve their fatigue resistance. For the study they were split into two groups of nine, one group taking 20g of creatine daily and the other a placebo preparation for a period of five days. Before and after supplementation they completed one 100m sprint and a series of six intermittent 60m sprints starting every 50secs.

Key results were as follows:

1. Only one of the sprinters was able to identify correctly whether he had received creatine or placebo;
2. Although no significant body weight changes were seen in the placebo group, a significant increase of 0.6kg was seen in the creatine group;
3. Blood creatine levels were unchanged in the placebo group but increased significantly in the creatine group;
4. The 100m sprint times and 60m split times were not statistically different after supplementation with placebo. But creatine supplementation resulted in significant improvements, reducing the 100m sprint time from 11.68 to 11.59secs and reducing the total time of the six intermittent 60m sprints from 45.63 to 45.12secs.
'An increased performance could be a result of the increased amount of PCr [creatine phosphate] available in skeletal muscle, since the amount of PCr is one of the most likely limitations to muscle performance during brief, high power exercise,' suggest the researchers.'Increased PCr in skeletal muscle may delay the depletion of PCr stores and maintain ATP turnover rate, suggesting increased energy availability during heavy exercise.'
The benefit of an improvement in 100m sprint time is self-evident, as the researchers point out, but the value of improved intermittent 6x60m sprint times is less obvious.'It may suggest that each training component can be performed at a higher quality level and thus Cr supplementation may improve the quality of training, leading to greater gains in sprint performance.'
From the sprinter's perspective, the news about creatine looks good. However, the researchers take a cautious view that, although there have been no reports of serious side effects with creatine supplementation, further investigation of the effects of long-term use should now be carried out.

Scand J Med Sci Sports 2001 Apr 11(2), pp96-102



Isabel Walker