The Effects of Creatine Supplementation on Short-Term Exercise Performance of U.S. Navy Seals
Abstract
Dietary creatine (Cr) supplementation is currently a common practice among athletes and U.S. Naval Special Warfare personnel. The ergogenic effect of supplemental Or has been demonstrated under certain well-controlled laboratory conditions, but the evidence supporting Cr use to augment performance under operational or field conditions is equivocal. This investigation was designed to evaluate the effects of dietary Cr supplementation on the performance of military tasks by U.S. Navy Sea Air and Land (SEAL) personnel. SEAL volunteers, ages 23 to 42 years, performed two familiarization time trials and a baseline (control) obstacle course (OC) time trial lasting -2 min. Using a randomized, double-blind protocol, each subject consumed 20 g/d of artificially sweetened Or (n = 12) or polycose placebo (n = 12) for 5 days. Within 24-hr after consuming the final dose, a post-treatment OC time trial was performed. Body composition and total body water was measured before the control and post-treatment OC time trials. Blood lactate levels were measured at 5 and 10 min after completion of the control and post-treatment OC time trials. Treatment effects were assessed by repeated measures ANOVA. Group differences for percent body fat, hydration status, and age were noted after group assignment but were unrelated to Cr supplementation. Five days of Cr supplementation at 20 g/d had no significant effect (p > 0.1) on body composition, total body water, blood lactate, or OC performance time. The small effects on performance seen in some laboratory studies with Cr supplementation do not appear to carry over to field-related tasks conducted in an operational setting.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1999
- Accession Number
- ADA387182
Entities
People
- H. W. Goforth Jr.
- I. Jacobs
- P. G. Law
- W. .k. Prusaczyk
- W. Y. Ensign Jr.
Organizations
- Naval Health Research Center