Creatine promotes intracellular water retention, but that’s considered beneficial, since one potent signal of anabolism is cellular swelling due to hydration. Some scientists even suggest that it may be the mechanism through which creatine exerts its anabolic effects. Another theory suggests that merely by providing energy, creatine fosters an anabolic effect when combined with exercise. The protein synthesis process is energy intensive, but that energy is mainly supplied by fat.
A recent study takes a different approach to the question of how creatine may promote muscle gains.1 The premise was that creatine may promote an anabolic response in muscle by upgrading certain anabolic hormones—specifically, the activity of insulinlike growth factor 1 in muscle. When produced locally in muscle under the impetus of intense exercise, IGF-1 promotes the activity of a number of substances actively involved in the muscle growth process. In addition, IGF-1 promotes satellite cell activity, which is required for muscle growth and repair after hard training.
Six healthy young men were divided into two groups. One group got 21 grams a day of oral creatine monohydrate for five days, while the other group got a placebo (maltodextrin, a carbohydrate). The maltodextrin placebo was mixed with protein and given three hours after exercise.
In the subjects who got creatine, IGF mRNA, a marker of increased IGF-1, increased by 30 to 40 percent under resting conditions. IGF-2 also increased in the creatine group. Exercise alone increased those hormones, and the effect with creatine wasn’t cumulative, but the creatine group experienced elevated resting IGF-1 levels, an effect not seen in the placebo group.
The researchers who conducted the study think that the elevation of IGF-1 is responsible for the creatine-related anabolic effects in muscle.
©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.
