PURPOSE: One limitation shared by all published carbohydrate-loading regimens is that 2-6 d are required for the attainment of supranormal muscle glycogen levels. Because high rates of glycogen resynthesis are reported during recovery from exercise of near-maximal intensity and that these rates could in theory allow muscle to attain supranormal glycogen levels in less than 24 h, the purpose of this study was to examine whether a combination of a short bout of high-intensity exercise with 1 d of a high-carbohydrate intake offers the basis for an improved carbohydrate-loading regimen. METHODS: Seven endurance-trained athletes cycled for 150 s at 130% VO2peak followed by 30 s of all-out cycling. During the following 24 h, each subject was asked to ingest 12 g.kg-1 of lean body mass (the equivalent of 10.3 g.kg-1 body mass) of high-carbohydrate foods with a high glycemic index. RESULTS: Muscle glycogen increased from preloading levels (+/- SE) of 109.1 +/- 8.2 to 198.2 +/- 13.1 mmol.kg-1 wet weight within only 24 h, these levels being comparable to or higher than those reported by others over a 2- to 6-d regimen. Densitometric analysis of muscle sections stained with periodic acid-Schiff not only corroborated these findings but also indicated that after 24 h of high-carbohydrate intake, glycogen stores reached similar levels in Type I, IIa, and IIb muscle fibers. CONCLUSION: This study shows that a combination of a short-term bout of high-intensity exercise followed by a high-carbohydrate intake enables athletes to attain supranormal muscle glycogen levels within only 24 h.
PURPOSE: One limitation shared by all published carbohydrate-loading regimens is that 2-6 d are required for the attainment of supranormal muscle glycogen levels. Because high rates of glycogen resynthesis are reported during recovery from exercise of near-maximal intensity and that these rates could in theory allow muscle to attain supranormal glycogen levels in less than 24 h, the purpose of this study was to examine whether a combination of a short bout of high-intensity exercise with 1 d of a high-carbohydrate intake offers the basis for an improved carbohydrate-loading regimen. METHODS: Seven endurance-trained athletes cycled for 150 s at 130% VO2peak followed by 30 s of all-out cycling. During the following 24 h, each subject was asked to ingest 12 g.kg-1 of lean body mass (the equivalent of 10.3 g.kg-1 body mass) of high-carbohydrate foods with a high glycemic index. RESULTS: Muscle glycogen increased from preloading levels (+/- SE) of 109.1 +/- 8.2 to 198.2 +/- 13.1 mmol.kg-1 wet weight within only 24 h, these levels being comparable to or higher than those reported by others over a 2- to 6-d regimen. Densitometric analysis of muscle sections stained with periodic acid-Schiff not only corroborated these findings but also indicated that after 24 h of high-carbohydrate intake, glycogen stores reached similar levels in Type I, IIa, and IIb muscle fibers. CONCLUSION: This study shows that a combination of a short-term bout of high-intensity exercise followed by a high-carbohydrate intake enables athletes to attain supranormal muscle glycogen levels within only 24 h.
Authors: D P M Maclaren; H Mohebbi; M Nirmalan; M A Keegan; C T Best; D Perera; M N Harvie; I T Campbell Journal: Eur J Appl Physiol Date: 2011-02-01 Impact factor: 3.078
Authors: V A F Tarini; L C Carnevali; R M Arida; C A Cunha; E S Alves; M C L Seeleander; B Schmidt; F Faloppa Journal: J Physiol Biochem Date: 2012-11-27 Impact factor: 4.158
Authors: Chad M Kerksick; Shawn Arent; Brad J Schoenfeld; Jeffrey R Stout; Bill Campbell; Colin D Wilborn; Lem Taylor; Doug Kalman; Abbie E Smith-Ryan; Richard B Kreider; Darryn Willoughby; Paul J Arciero; Trisha A VanDusseldorp; Michael J Ormsbee; Robert Wildman; Mike Greenwood; Tim N Ziegenfuss; Alan A Aragon; Jose Antonio Journal: J Int Soc Sports Nutr Date: 2017-08-29 Impact factor: 5.150