Creatine supplementation enhances intermittent work performance.
To determine the impact of creatine supplementation on high-intensity, intermittent work, 18 participants each performed 2 sets of 4 different work bouts to exhaustion. For 5 days prior to the first set of work bouts, all participants received a placebo (5 g of calcium chloride daily). For the second set of work bouts, 9 participants again received the placebo, while the other 9 received creatine supplementation (18.75 g creatine monohydrate daily for 5 days prior to and 2.25 g creatine daily during testing). The four work bouts in each set consisted of cycling to exhaustion at 150% peak oxygen uptake (VO2peak) either nonstop (A), intermittently for either 60-s work/120-s rest periods (B), 20-s work/40-s rest (C), or 10-s work/20-s rest (D). Creatine supplementation significantly increased (p < .01) the total work time of all bouts. Protocol D showed the greatest increase (> 100%); C increased 61.9%; B increased 61.0%; and A increased 23.5%. These results demonstrate that creatine supplementation significantly extends one's capacity to maintain a specific level of high-intensity, intermittent exercise.
Prevost
M C
MC
Marine Corps Air Station, EI Toro, USA.
Nelson
A G
AG
Morris
G S
GS
D000328:Adult; D015308:Anaerobic Threshold / Q000187:drug effects; D000704:Analysis of Variance; D001642:Bicycling; D003401:Creatine / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D016014:Linear Models; D008297:Male; D018763:Muscle Fatigue / Q000187:drug effects; D010101:Oxygen Consumption; D010807:Physical Endurance / Q000187:drug effects; D005082:Physical Exertion / Q000187:drug effects*; D013997:Time Factors
D019344:Lactic Acid; D003401:Creatine