How does creatine increase muscle size and strength?
Answer: In a comprehensive review of the scientific literature related to creatine supplementation presented at the National Strength and Conditioning Association’s 21st Annual Meeting, Dr. Kreider notes there are two main theories for increased muscle size and strength from creatine supplementation. A third and more controversial theory related to creatine’s effects on anabolic hormone levels has been proposed, but further research needs to be carried out to confirm these effects.
Theory #1: Enhanced quality of training
Creatine in the muscle is an essential component to the production of ATP, the body’s energy molecule. More available energy may allow for longer, more intense and more frequent bouts of physical activity. Thus, creatine supplementation, studies show, may produce noticeable effects in muscle size and strength by enhancing energy reserves in the muscle cells.
Theory #2: Cell “volumization”
It’s well-documented in the scientific literature that as creatine is taken up into the muscle cells, it also associates with water. “As more creatine is stored, more water may be brought into the muscle,” says biochemist and creatine researcher Dr. Richard A. Passwater. “When muscle cell volume is increased, it is thought that this triggers more protein and glycogen synthesis, reduces protein breakdown (proteolysis) and increases muscle mass.”
Theory #3: Anabolic hormone increase
According to a team of researchers from Chukyo University in Toyota, Japan, creatine may in fact have direct anabolic properties due to its effect on enhancing human growth hormone secretion. Dr. J.M. Schedel and colleagues found that subjects who loaded with 20 grams of creatine showed a “significant stimulation” of growth hormone between two and six hours after ingestion versus those who were given a placebo.
The researchers concluded that, in resting conditions and at loading dosages, creatine supplementation mimics the response of intense exercise, which also stimulates growth hormone secretion. This, they say, could partly explain the dramatic muscle size and strength increases observed after creatine loading and should, along with other factors, be considered when investigating just how creatine works its magic.