Effects of Oral Creatine Supplementation on Power Output during Repeated Treadmill Sprinting

Abstract

The aim of the present study was to examine the effects of creatine (Cr) supplementation on power output during repeated sprints on a non-motorized treadmill. Sixteen recreationally active males volunteered for this study (age 25.5 ± 4.8 y, height 179 ± 5 cm, body mass 74.8 ± 6.8 kg). All participants received placebo supplementation (75 mg of glucose·kg−1·day−1) for 5 days and then performed a baseline repeated sprints test (6 × 10 s sprints on a non-motorised treadmill). Thereafter, they were randomly assigned into a Cr (75 mg of Cr monohydrate·kg−1·day−1) or placebo supplementation, as above, and the repeated sprints test was repeated. After Cr supplementation, body mass was increased by 0.99 ± 0.83 kg (p = 0.007), peak power output and peak running speed remained unchanged throughout the test in both groups, while the mean power output and mean running speed during the last 5 s of the sprints increased by 4.5% (p = 0.005) and 4.2% to 7.0%, respectively, during the last three sprints (p = 0.005 to 0.001). The reduction in speed within each sprint was also blunted by 16.2% (p = 0.003) following Cr supplementation. Plasma ammonia decreased by 20.1% (p = 0.037) after Cr supplementation, despite the increase in performance. VO2 and blood lactate during the repeated sprints test remained unchanged after supplementation, suggesting no alteration of aerobic or glycolytic contribution to adenosine triphosphate production. In conclusion, Cr supplementation improved the mean power and speed in the second half of a repeated sprint running protocol, despite the increased body mass. This improvement was due to the higher power output and running speed in the last 5 s of each 10 s sprint.

Effects of Creatine Supplementation after 20 Minutes of Recovery in a Bench Press Exercise Protocol in Moderately Physically Trained Men

“…Furthermore, although in Set 3 there was no statistical significance, the CR group performed 12.7% more repetitions. These results are in line with those of previous studies, which consistently report that CR supplementation increases the capacity to recover between peaks of intermittent activity during different types of exercise, such as repeated Wingate efforts [ 26 , 47 ], rowing sprints [ 48 ], cycling sprints [ 14 , 24 , 25 , 49 ], running sprints [ 28 , 29 , 30 , 31 ], swimming sprints [ 32 ], resistance exercise [ 33 , 34 , 47 ], and maximal voluntary isokinetic contractions [ 15 ]. This could be due to the increase in the content of intramuscular PCr produced by the CR supplementation, since increases of 10–40% in the content of PCr have been previously reported [ 6 ], as well as increases in the amount of PCr re-synthesis during the different recovery periods [ 50 ].…”

“…This could indicate that subjects who were supplemented with CR, despite them having performed more mechanical work, obtained a similar value of metabolic stress. Previous studies report similar results, with constant blood lactate and pH values, suggesting that anaerobic glycolysis is not altered by CR supplementation [ 31 ]. On the same vein, other studies have shown that CR supplementation did not alter the blood lactate concentrations after 3.5 min of recovery following intermittent sprints in soccer players [ 29 ], nor immediately or one hour after performing 6 35 m sprints at a maximum speed with 10 s of recovery between the sprints [ 30 ].…”

“…In addition to the improvements in performance in a single session using a maximum amount of effort, creatine appears to maintain a top performance in multiple exercise sets, thus improving recovery [ 20 ]. Sprint improvements have been reported in cycling [ 14 , 24 , 25 , 26 , 27 ], running [ 28 , 29 , 30 , 31 ], and swimming [ 32 ]. Regarding the strength protocols in which multiple sets are performed until muscle failure occurs with submaximal loads, improvements have also been reported in muscular performance after short-term creatine supplementation [ 33 , 34 ].…”

Sporcular Tarafindan Kullanilan Doğal Kaynakli Ergojeni̇k Destekler

“…İskelet kaslarındaki kreatin miktarının optimal düzeyde olması yüksek miktarda fosfokreatin depolarına katkı sağlamaktadır. Bu durum yapılan egzersizin şiddeti ile birlikte ATP (Adenozin trifosfat) hidrolizi hızının belirlenmesine katkı sağladığından önem arz etmektedir [1,3,5,20,[29][30][31][32][33].…”

“…Kreatin takviyesi, kısa süreli, yüksek yoğunluklu egzersizlerde, güç ve etkinliğin yanı sıra yağsız vücut kütlesini de artırmaktadır. Bu özelliği nedeniyle en yüksek kullanımın güreşçiler tarafından olduğu bilinmektedir [1,20,[29][30][31][32][33].…”