Introduction: Age-related sarcopenia and dynapenia have negative effects on strength and the ability to perform activities of daily living. Resistance training (RT) increases muscle mass and strength in older adults and is an established countermeasure for sarcopenia and dynapenia, and creatine may enhance this effect. We aimed to determine whether the addition of Cr to RT increased gains in muscle mass, strength, and function in older adults over RT alone by conducting a systematic review and meta-analysis.
Methods: PubMed and Healthstar databases were searched. Randomized, placebo-controlled trials that involved older adults supplemented with Cr and included RT regimens (>6 wk) were included. Data were analyzed using fixed or random (if data were heterogeneous) effects meta-analysis using RevMan 5.
Results: The meta-analysis comprised 357 older adults (average ± SD Cr: 63.6 ± 5.9 yr, Pl: 64.2 ± 5.4 yr) with 12.6 ± 4.9 wk of RT. Cr + RT increased total body mass (P = 0.004) and fat-free mass (P < 0.0001) with no effect on fat mass as compared with RT alone. Cr + RT increased chest press (P = 0.004) and leg press (P = 0.02) one-repetition maximum to a greater extent than RT alone, with no difference in the effect on knee extension or biceps curl one-repetition maximum, isokinetic or isometric knee extension peak torque. Cr + RT had a greater effect than RT alone on the 30-s chair stand test (P = 0.03).
Conclusion: Retention of muscle mass and strength is integral to healthy aging. The results from this meta-analysis are encouraging in supporting a role for Cr supplementation during RT in healthful aging by enhancing muscle mass gain, strength, and functional performance over RT alone; however, the limited number of studies indicates further work is needed.
Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, CANADA
Address for correspondence: Stuart Phillips, Ph.D., Ivor Wynne Centre, E210, McMaster University, 1200 Main St. W, Hamilton, Ontario L8S 4K1, Canada; E-mail: firstname.lastname@example.org.
Submitted for publication September 2013.
Accepted for publication November 2013.