Dr. Earnest Study
Dr. Earnest conducted a study investigating the influence of creatine monohydrate supplementation on muscular power and strength in 10 experienced weight trained male subjects.
Three series of high intensity, anaerobic type muscular workouts were used.
The first series consisted of three consecutive 30 second Wingate bike tests, followed by five minuets of rest. Peak anaerobic power was defined as the greatest power achieved in a given five second work interval.
Anaerobic work was defined as the total amount of work performed in a 30 second period. The second series used a one repetition maximum (lRM) free weight bench press as a test of muscular strength.
The third series utilized complete lifting repetitions at 70% of the bench press IRM until fatigue. Fatigue was defined as the inability to complete one lifting repetition or the inability to maintain a lifting cadence of one second eccentric and one second concentric (lifting and lowering the weight).
Total lifting volume was calculated as 70% of pre-test IRM multiplied by the number of complete lifting repetitions. Subjects received either a glucose placebo or creatine monohydrate supplement in a double blind fashion. (After 14 days of supplementation, each subject was re-tested on the Wingate bike tests.
Re-testing for the weight lifting trials was done after 28 days of supplementation.
Within the creatine group, total anaerobic work from the Wingate tests was significantly higher during all post-test trials.
The increases were (13%) for series one, 18% for series two and 18% for series three. No changes were noted in the placebo group. Greater total anaerobic work resulted from the creatine subject's ability to achieve and maintain higher levels of anaerobic power consistently over- each five second time interval.
Bench press IRM increased (6% )in the creatine group. Total lifting volume was significantly higher within the creatine group, whether expressed in absolute terms (26%) or relative terms (29%).
Increases in the total lifting volume were associated with the ability of the creatine group to perform (26%) more lifting repetitions.
The authors conclude that the ability of the creatine group to perform a greater total lifting volume demonstrates the effectiveness of creatine as an ergogenic aid.