The Effects of Polyethylene Glycosylated Creatine Supplementation on Muscular Strength and Power

Another article on PEG-Creatine

Journal of Strength & Conditioning Research:

December 2010 - Volume 24 - Issue 12 - pp 3343-3351

Abstract

Camic, CL, Hendrix, CR, Housh, TJ, Zuniga, JM, Mielke, M, Johnson, GO, Schmidt, RJ, and Housh, DJ. The effects of polyethylene glycosylated creatine supplementation on muscular strength and power. J Strength Cond Res 24(12): 3343-3351, 2010-The purpose of the present investigation was to examine the effects of 28 days of polyethylene glycosylated creatine (PEG-creatine) supplementation on 1-repetition maximum bench press (1RM_BP) and leg extension (1RM_LE), mean power (MP), and peak power (PP) from the Wingate Anaerobic test and body weight (BW). This study used a randomized, double-blind, placebo-controlled, parallel design. Twenty-two untrained men (mean age ± SD = 22.1 ± 2.1 years) were randomly assigned to either a Creatine (n = 10) or Placebo (n = 12) group. The Creatine group ingested PEG-creatine (5 g·d⁻¹), whereas the Placebo group ingested maltodextrin powder (5 g·d⁻¹). All subjects performed bench press and bilateral leg extension exercises to determine their 1RM values, and 2 consecutive Wingate Anaerobic Tests (separated by 7 minutes) on a cycle ergometer to determine MP and PP before supplementation (day 0) and after 7 (day 7) and 28 (day 28) days of supplementation. The results indicated that there was a significant (p <>BPbetween days 0 and 28 for the Creatine group but not for the Placebo group. There were no significant changes, however, in 1RM_LE, MP, PP, or BW for the Creatine or Placebo group. These findings indicated that 28 days of PEG-creatine supplementation without resistance training increased upper body strength but not lower body strength or muscular power. These findings supported the use of the PEG-creatine supplement for increasing 1RM_BP strength in untrained individuals.

* This was an old article about PEG Creatine that GNC had done to validate one of their products as being as effective as Creatine Monohydrate

Effects of Creatine Monohydrate and Polyethylene Glycosylated Creatine Supplementation on Muscular Strength, Endurance, and Power Output.

Original Research

Journal of Strength & Conditioning Research. 23(3):818-826, May 2009.
Herda, Trent J 1; Beck, Travis W 1; Ryan, Eric D 1; Smith, Abbie E 1; Walter, Ashley A 1; Hartman, Michael J 2; Stout, Jeffrey R 1; Cramer, Joel T 1

Abstract:
Herda, TJ, Beck, TW, Ryan, ED, Smith, AE, Walter, AA, Hartman, MJ, Stout, JR, and Cramer, JT. Effects of creatine monohydrate and polyethylene glycosylated creatine supplementation on muscular strength, endurance, and power output. J Strength Cond Res 23(3): 818-826, 2009-The purpose of this study was to examine the effects of a moderate dose of creatine monohydrate (CM) and two smaller doses of polyethylene glycosylated (PEG) creatine on muscular strength, endurance, and power output. Fifty-eight healthy men (mean +/- SD: age, 21 +/- 2 years; height, 176 +/- 6 cm; body mass [BM], 75 +/- 14 kg) volunteered and were randomly assigned to 1 of 4 groups: (a) placebo (PL; 3.6 g of microcrystalline cellulose; n = 15), (b) CM (5 g of creatine; n = 13), (c) small-dose PEG creatine (1.25 g of creatine: PEG1.25; n = 14), or (d) moderate-dose PEG creatine (2.50 g of creatine: PEG2.50; n = 16). Testing was conducted before (pre-) and after (post-) a 30-day supplementation period. Measurements included body mass, countermovement vertical jump (CVJ) height, power output during the Wingate test (peak power [PP] and mean power [MP]), 1 repetition maximum bench press (1RMBP), 1RM leg press (1RMLP) strength, and repetitions to failure at 80% of the 1RM for bench press (REPBP) and leg press (REPLP). BM and MP (W) increased (p <= 0.05) from pre- to postsupplementation for the CM group only, whereas 1RMBP and 1RMLP increased (p <= 0.05) for the CM, PEG1.25, and PEG2.50 groups. CVJ height (cm and cm[middle dot]kg-1), MP (W[middle dot]kg-1), PP (W and W[middle dot]kg-1), REPBP, and REPLP increased (p <= 0.05) for all groups. These findings indicated that the recommended safe dose of 5 g[middle dot]d-1 of CM increased BM and improved muscle strength (1RMBP and 1RMLP). Smaller doses of PEG creatine (1.25 and 2.50 g[middle dot]d-1) improved muscle strength (1RMBP and 1RMLP) to the same extent as 5 g[middle dot]d-1 of CM, but did not alter BM, power output, or endurance. When compared to the PL group, neither CM nor PEG creatine supplementation improved peak power output (CVJ or PP), MP, or muscle endurance (REPBP or REPLP). Thus, PEG creatine may have ergogenic effects that are comparable to those of CM, but with a smaller dose of creatine.