Creatine Builds Muscle
September 6, 1999
According to a new study, research gives biological support to athletes' perceptions that they get stronger when they take creatine.
The 12-week study found that muscle fibers change in athletes who use creatine, and these athletes can lift more weight than athletes who don't. The athletes may be getting a training edge from the supplement's ability to let muscles keep drawing energy, the study said.
"You are being able to increase the intensity of the individual training session," researcher Jeff S. Volek of Ball State University, Muncie, Ind., said. "Over 12 weeks, those extra couple of reps every workout add up."
The study, done while Volek was at Penn State, was published in the August issue of the American College of Sports Medicine journal Medicine and Science in Sports and Exercise.
Creatine supplements work by helping the body replenish adenosine triphosphate, known as ATP, which is a key source of energy for muscle. The body makes creatine, although it also can be found in meat. To try to ensure their cells are saturated with creatine, however, many athletes use supplements.
Volek and his colleagues looked at 19 men, all about 25 years of age and similar in weight, lean body mass and capacity to lift weights. Ten were given creatine —— 25 grams a day for the first week, followed by 5 grams a day for the rest of the study. The rest were given a fake preparation. No one was told what they were getting. All the men worked out under the guidance of the same trainer.
At the end of the training, all the men were bigger than they were at the start. But the men on creatine registered an average 6.3 percent gain in fat-free mass, compared with 3.1 percent in those on the placebo.
Cross-sectional samples of muscle fiber showed increases of about 35 percent in fiber size in men on creatine, compared with gains ranging from 6 percent to 15 percent in non-creatine group, depending on the type of muscle sampled. And men on creatine showed a 24 percent increase in their bench press, compared with 16 percent for the men not on creatine.
"We were blasting the placebo group just as hard, and we are still seeing these effects," Volek said.
The findings are in line with some other recent research that extended creatine's apparent benefits. In a study of sedentary young women in Belgium, 10 weeks of resistance training on creatine resulted in greater strength gains than 10 weeks of similar training by women without it. Initial studies on creatine had found only short bursts of performance gains.
In Volek's study, he said, the supplement itself probably did not make the muscles more powerful but did let the athletes who used it keep training while their non-using colleagues flagged.
Based on that, creatine apparently can provide a base on which to build strength, but this is not the same as a chemical margin of victory, Volek said. Too many other factors go into sports for that to be the case, he said.
Also, athletes may expect too much of the supplement —— athletes who don't use it still make gains, and athletes who use illegal steroids make bigger ones, Volek said.
But many athletes do expect their performance to improve because of the supplement. And a researcher unconnected to the study thinks they have a right to. "We have seen 14 to 20 pounds of muscle and huge amounts of strength," said Richard B. Kreider of the University of Memphis.
However, another expert wonders how much of the strength improvement in the new study can be attributed without doubt to the creatine. Athletes know when they are bulking up, and the ones in Volek's study