Med Sci Sports Exer 1999,31(3):464–471.CrossRef 19. Borg G: Borg’s Perceived Exertion and Pain Scales. Champaign: Human Kinetics; 1998. 20. Faul F, Erdfelder E, Lang AG, Buchner A: G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav

Res Methods 2007, 39:175–191.PubMedCrossRef 21. Pfeiffer B, Stellingwerff T, Zaltas E, Hodgson AB, Jeukendrup AEL: Carbohydrate oxidation from a drink during compared with cycling exercise. Med Sci Sports Exer 2011,43(2):327–334.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions AC conceived the study. AC and HR developed the design of the study. AC recruited participants, screened participants, this website collected all data, developed all sport drinks tested, performed statistical analyses, and wrote the manuscript. HR helped to draft the manuscript. DL contributed to the study design and helped draft the manuscript. All authors

read and approved the final manuscript.”
“Background Competitive sports performance is strongly dependent on optimal muscle function. During cycling exercise across the heavy and severe intensity domains [1], energy is provided more and more by anaerobic glycolysis. This leads to an increased rate of accumulation of metabolites, which have been linked with learn more muscle fatigue (e.g. Pi, ADP, H+, and extracellular K+). Cycling exercise at the threshold between the heavy and severe domain, i.e. at ‘Critical Power’ (CP), can, in contrast to the theoretical concept

[2], only be sustained for as long as 20 to 40 min [3] before task failure. Furthermore, it was shown that CP overestimates the highest possible metabolic www.selleck.co.jp/products/MDV3100.html steady state [4, 5] and, consequently, that exercise at or above CP is associated with a decline in muscle and blood pH [6, 7]. An selleck kinase inhibitor activity-induced decrease in intracellular pH has been suggested to limit exercise because it inhibits glycogenolysis and glycolysis [8], increases muscular K+-release [9] and inhibits sarcoplasmatic Ca2+-release [10, 11]. Furthermore, it induces a metabolic acidosis that might impair muscle function [12] and compromise performance. To blunt the fall in intracellular pH and prolong time-to-exhaustion (T lim), nutritional modulation might be a promising avenue. With respect to endurance exercise, to date especially sodium bicarbonate (NaHCO3) has gained much attention. However, the mechanisms by which NaHCO3 ingestion may enhance performance are not fully understood. It is believed that NaHCO3 ingestion leads to an increase in blood bicarbonate concentration ([HCO3 -]), which in turn increases extracellular buffer capacity. More precisely, it is proposed that the higher [HCO3 -] gradient between blood and the intramyocellular compartment enhances H+-efflux out of the muscle cell, thereby delaying the fall in intracellular pH [13], which in turn may delay an impairment in optimal muscle function and performance [14, 15].