Creatine Not Solution for Lost Muscle

Data from a recent randomized controlled trial published in the January issue of Sports Medicine suggests that creatine loading has no effect on muscle mass and strength during leg immobilization.

Evelien Backx, Ph.D. student at Wageningen University in The Netherlands and one of the researchers involved in the trial, explained that prior studies have found that creatine supplementation (20 g/d) can increase lean mass over a period of about five days, and that it has become a popular supplement to enhance muscle growth in athletes. Because of this, Backx and colleagues hypothesized that creatine supplementation would be an effective strategy to prevent the loss of muscle mass during leg immobilization.

In this study, 30 healthy young men in their early 20s were randomly assigned to either a creatine or placebo group. The men either received a placebo or creatine supplements (20 g/d) for five days before one leg was immobilized in a full cast for seven days.

Despite an increase in muscle total creatine content in the creatine group, quadriceps muscle cross-sectional area declined in both the creatine (465 mm²) and the placebo group (425 mm²). There were no differences between the groups (p = 0.76). Leg muscle strength also decreased in both groups (p = 0.20). No changes were found in muscle fiber size in either group, however (p > 0.05).

“Short-term muscle inactivity leads to substantial losses in muscle mass and strength. We show that merely seven days of inactivity leads to 5.5±0.5 % loss of muscle mass (-0.8% per day), ” Backx told OTW.

“In contrast to what we expected, creatine supplementation cannot prevent the loss of muscle mass or strength during a period of inactivity. We also show that creatine supplementation does not enhance the recovery from muscle mass loss after a period of muscle inactivity, ” Backx said.

“However, as shown by a previous study (Hespel et al., 2001), creatine supplementation can be effective to enhance muscle mass regain when it is combined with 3-10 weeks of strength training.”

“The loss of muscle mass and strength during disuse is associated with a longer recovery period, a higher risk of injury reoccurrence and a decline in metabolic health. Hence, it is important to find strategies that can limit the loss of muscle mass during inactivity.”

Backx called for the continual search for an effective strategy to prevent the loss of muscle mass.