Background and Objectives: The effect of creatine monohydrate loading on exercise-induced apoptosis is unclear. The purpose of this study was to examine the effect of creatine supplementation on apoptosis at acute resistance exercise in men.

Materials and Methods: In a randomized, placebo controlled, clinical trial study, twenty 42-49 middle-aged year men were randomly assigned to supplement with 20 g per day of creatine monohydrate or placebo (maltodextrin) similarly for one week. On the 8^th day, the subjects performed an acute resistance exercise with 80% of one repetition maximum. Blood samples were collected a day before supplementation loading (Pre) and immediately post-acute exercise (Post) for the measurement of serum p53, caspase 8 and Insulin-like growth factor 1 (IGF-1) concentrations. Data were analyzed by Student’s paired and unpaired t tests at the significant level of P<0.05.

Results: P53 serum [Pre: 486.41±40.98, Post: 842.20±170.86 ng/L (p=.000)] and caspase 8 [Pre=8.36±1.26, Post: 11.66±4.15 ng/ml (p=.031)] levels were significantly increased in the placebo group immediately post-acute exercise. Also IGF-1 was significantly increased in both groups. The p53 level was significantly higher in the placebo group as compared to the creatine group immediately post-acute exercise (P<0.05).

Conclusion: The results indicated that creatine monohydrate loading can inhibit acute resistance-induced apoptosis in middle-aged. Thus, one week creatine supplementation may be a useful strategy for preventing apoptosis by extensive acute exercise.

Keywords: Apoptosis, Creatine monohydrate, Caspase 8, p53, Resistance exercise