Does creatine work?

A 60 year old gym acquaintance who is a physician recommended taking creatine, so I decided to do a little Web research. Most of what I found indicated that creatine helps build strength and muscle.

For example, the article The Effects of Creatine Supplementation on Body Composition, Muscular Strength and Power presents an experiment with 36 female college volleyball players. Sixteen were given creatine and 16 a placebo during a ten week strength training program. The placebo group improved their single rep maximum bench press from 47.4 to 50.3 kilograms while the creatine group improved from 47.6 to 55.2. Another article, Creatine supplementation combined with resistance training in older men, concludes that creatine supplementation, when combined with resistance training, increases lean tissue mass and improves leg strength, endurance, and average power in men of mean age 70 yr.

Creatine supplementation and exercise performance: recent findings is a survey article covering studies between 1999 and 2005. Some of the conclusions are:

• [Creatine] appears to be most effective for activities that involve repeated short bouts of high-intensity physical activity.
  
• When maximal force or strength (dynamic or isotonic contractions) is the outcome measure following Cr ingestion, it generally appears that Cr does significantly impact force production regardless of sport, sex or age.
  
• The evidence is much more equivocal when investigating isokinetic force production and little evidence exists to support the use of Cr for isometric muscular performance.
  
• There is little benefit from Cr ingestion for the prevention or suppression of muscle damage or soreness following muscular activity.
  
• When performance is assessed based on intensity and duration of the exercises, there is contradictory evidence relative to both continuous and intermittent endurance activities.
  
• Activities that involve jumping, sprinting or cycling generally show improved sport performance following Cr ingestion.
  
• There appears to be no strong scientific evidence to support any adverse effects but it should be noted that there have been no studies to date that address the issue of long-term Cr usage.

Another survey, Dietary Supplements and Sports Performance: Metabolites, Constituents, and Extracts (one article in a six-article series on supplements), reaches similar conclusions. There are also Wikipedia articles on Creatine and Creatine supplements.

Since I am into weight lifting and bike riding, I think I'll give it a try.

The survey I summarized above notes that the most common program involves an initial loading phase of 20 g/day for 5-7 days, followed by a maintenance phase of 3-5 g/day for differing periods of time (1 week to 6 months). A dose calculator advised that I take 3.5 mg per day and skip the initial loading phase since I am over 65. They also recommend combining it with vitamins b6, b12 and folic acid which you can get in one pill at Trader Joe's.

Have you used creatine? Did it work for you?