title: The effects of creatine monohydrate loading on anaerobic performance and one-repetition maximum strength.
abstract: The purpose of this study was to examine the effects of 7 days of supplementation with 20 g·d⁻¹ of creatine monohydrate (CM) on mean power (MP) and peak power (PP) from the Wingate anaerobic test (WAnT), body weight (BW), 1-repetition maximum (1RM) bilateral leg extension (LE) strength, and 1RM bench press (BP) strength. This study used a randomized, double-blind, placebo-controlled design. Twenty-two men (mean ± SD: age = 22.1 ± 2.0 years; height = 178.0 ± 5.8 cm; body weight [BW] = 77.6 ± 7.6 kg) were randomly assigned to either a supplement (SUPP; n = 10) or placebo (PLAC; n = 12) group. The SUPP group ingested 20 g·d⁻¹ of CM powder for 7 days, whereas the PLAC ingested 20 g·d⁻¹ of maltodextrin powder. Measurements for the PLAC and SUPP groups included BW, PP, and MP from two 30-second WAnTs (separated by 7 minutes), and 1RM strength for LE and BP. Testing was conducted before (PRE) and after (POST) 7 days of ingesting either the supplement or placebo. The results of this study indicated that there was a significant (p ≤ 0.05) increase from PRE to POST testing in MP for the SUPP group (5.4%) but not for the PLAC group (-0.3%). There were no between-group differences, however, for 1RM LE and 1RM BP strength. Furthermore, there were no changes in PP or BW for either group. The findings of this study indicated that loading with 20 g·d⁻¹ of CM for 7 days increased MP (5.4% increase) from the WAnT, but it had no effect on strength (1RM LE and 1RM BP), PP, or BW.
authors.affiliation: Department of Kinesiology, School of Allied Health, Western New Mexico University, Silver City, New Mexico, USA. zunigaj@wnmu.edu
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Zuniga
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Housh
authors.forename: Clayton L
authors.initials: CL
authors.lastname: Camic
authors.forename: C Russell
authors.initials: CR
authors.lastname: Hendrix
authors.forename: Michelle
authors.initials: M
authors.lastname: Mielke
authors.forename: Glen O
authors.initials: GO
authors.lastname: Johnson
authors.forename: Dona J
authors.initials: DJ
authors.lastname: Housh
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Schmidt
mesh_terms: D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D003401:Creatine / Q000494:pharmacology*; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology; D005080:Exercise Test; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000187:drug effects*; D010807:Physical Endurance / Q000187:drug effects*; D055815:Young Adult
chemical_list: D003401:Creatine