Studies on Creatine, Strength, Adverse Events

NATICK, Mass.--Researchers from the U.S. Army ResearchInstitute of Environmental Medicine reported that creatine may have an effect onstrength and endurance. In a study appearing in November's The Journal ofStrength and Conditioning Research (16, 4:500-8, 2002) (http://nsca.allenpress.com),researchers led by John Warber determined the effects of creatinesupplementation on performance during military training tasks. Two groups of 13male soldiers each performed three consecutive military obstacle coursesseparated by five days; soldiers also completed a rifle marksmanship task onthree occasions and completed a bench press consisting of five sets to failure.Supplementation of either placebo or creatine, delivered via sports bars, wasgiven, with the creatine group given up to 24 g/d of creatine.

Creatine usage resulted in a significant increase (14 percent) in bench pressrepetitions, but no difference was seen between groups in terms of course runtimes. Neither marksmanship nor mood was affected by creatine. Those on creatinehad an average increase of 1.4 kg in body mass and a .5-percent decrease in bodyfat percentage.

It also appears that creatine has no long-term adverse effects on the kidneyor liver. In a study appearing in the December International Journal of SportNutrition and Exercise Metabolism (12, 4:453-60, 2002) (www.humankinetics.com),researchers from Truman State University, Kirksville, Mo., investigated theeffects of 5 g/d to 20 g/d over .25 to 5.6 years in 23 college football players.When noting serum creatinine, researchers reported that levels were notsignificantly different between groups.