Ingestion of creatine monohydrate immediately prior to exercise does not increase performance in creatine loaded individuals Academic Article uri icon

abstract

  • Twenty-four participants (15 men; 9 women) performed baseline testing (day 1) after following a standard unsupplemented diet. This was followed by the daily ingestion of a creatine formulation dietary loading sequence for 5 days (days 2-6, Phosphagen HP(TM) ; 5.25 g creatine mono-hydrate (CR) + 33 g dextrose). Loading consisted of 4 servings of Phosphagen HP(TM) per day. On day 7, participants were randomly assigned to one of three double-blind treatments administered 1 h before testing. During treatment, subjects were randomly fed: (a) 10 g of CR, (b) 80 g of dextrose, or (c) 10 g of CR + 80 g of dextrose. Variables evaluating the effectiveness of the different regimens included body mass, two 30-s Wingate anaerobic performance power tests and measurement of serum creatine concentration 65 and 5 min before each trial. Plasma ammonia concentration was also measured 65 min before and 5 min after each trial. The results of this trial show a significant non-placebo controlled effect for the pooled, group and gender data (P 0.05). Following 5 days of Phosphagen HP(TM) loading, significant pooled group mean changes were: (1) Body mass (+1.08 kg), (2) anaerobic power (1st Wingate = +1.28 kJ; 2nd Wingate 2 = (+1.92 kJ), (3) serum creatine concentration 65 min prior to testing trials (+624.06 molL-1) and (4) post-test plasma ammonia concentration (-83.63 molL-1). However, on day 7, in placebo group condition, no between group performance effects were noted following an acute 10 g oral bolus of CR 1 h prior to the exercise test. It is concluded that no performance benefit is due to acute ingestion of CR 1 h before exercise in CR loaded individuals.

published proceedings

  • Research in Sports Medicine

author list (cited authors)

  • Earnest, C. P., Whyte, B. O., BenEzra, V., Almada, A. L., & Beckham, S.

citation count

  • 1

complete list of authors

  • Earnest, Conrad P||Whyte, Bradley O||Benā€Ezra, Vic||Almada, Anthony L||Beckham, Susang

publication date

  • January 2000