Topic
Every study covered on this subject, newest first.
Nine well trained female cyclists were emptied of glycogen and then fed either a great deal of carbohydrate or almost none for the next day. Power at the first ventilatory threshold fell by nineteen watts, and gross cycling efficiency fell with it. The all out sprint at the end was unaffected.
European Journal of Applied · Main et al. · the Auckland University of Technology · 2 June 2026 · PMID 42228164
The only quantitative meta analysis of carbohydrate loading protocols pooled 30 studies and then tested which parts of the protocol predicted the size of the glycogen overshoot. Two variables mattered and four did not, and one of the four was maximal oxygen uptake.
Frontiers in Physiology 16:1620943 · Solem et al. · the Norwegian School of Sport Sciences · 18 August 2025 · PMID 40901614
Seven cyclists ate the same food in two different orders around an evening interval session. Going to bed with the carbohydrate already spent raised the fat side of the programme by morning, including a shift in DNA methylation. It did not raise the markers of mitochondrial building the practice is usually sold on.
Journal of Applied Physiology · Lane et al. · RMIT University · 25 June 2015 · PMID 26112242
Seven cyclists trained for five days on either a high fat or a high carbohydrate diet, then ate a full carbohydrate day. Muscle glycogen ended up identical. Pyruvate dehydrogenase activity did not. After the fat week it was lower at rest and throughout exercise, and glycogen was broken down more slowly.
American Journal of Physiology, · Stellingwerff et al. · the University of Guelph · 27 September 2005 · PMID 16188909
Seven men emptied their muscle glycogen with exhausting exercise, then ate either almost no carbohydrate or a great deal of it for two days. The high carbohydrate arm raised the glucose transporter message and lowered the message for the brake on burning carbohydrate. The low carbohydrate arm did the reverse on the fat side.
American Journal of Physiology, · Arkinstall et al. · RMIT University · 3 February 2004 · PMID 14761878
Twenty five men were put through either a depletion protocol or a taper only protocol and then fed identically for six days, with muscle glycogen measured every day by magnetic resonance. On day five the two protocols were level. On day seven the depletion group pulled ahead.
American Journal of Physiology, · Goforth et al. · the Naval Health Research Center · 5 August 2003 · PMID 12902321
Eight endurance trained men ate 10 grams of high glycaemic index carbohydrate per kilogram a day and did no training. Muscle glycogen roughly doubled within 24 hours and then stopped moving, and every fibre type had already reached its ceiling.
European Journal of Applied · Bussau et al. · the University of Western Australia · 28 May 2002 · PMID 12111292
An earlier trial had reported that women could not supercompensate muscle glycogen at all. When carbohydrate was prescribed per kilogram of lean body mass instead of as a share of habitual energy intake, women loaded as well as men.
European Journal of Applied · James et al. · the University of Western Australia · 1 October 2001 · PMID 11718281
Seven well trained cyclists rode a 100 kilometre time trial twice, once after carbohydrate loading and once after a placebo controlled moderate carbohydrate diet, eating carbohydrate during both rides. Loading raised muscle glycogen significantly and did not change the time.
Journal of Applied Physiology · Burke et al. · the Australian Institute of Sport · 1 April 2000 · PMID 10749820
Five well trained cyclists ate four weeks of a ketogenic diet with calories held constant. Glucose oxidation fell threefold, muscle glycogen use fell fourfold, and endurance time at a moderate pace was unchanged. This is the study the whole low carbohydrate argument in endurance sport is built on.
Metabolism 32(8):769 to 776 · Phinney et al. · 1 August 1983 · PMID 6865776
Trained runners went through three exercise and diet regimens before a 20.9 kilometre run. The classical severe depletion arm and a moderate carbohydrate arm reached the same muscle glycogen, and no arm produced a faster run.
International Journal of Sports · Sherman et al. · 1 May 1981 · PMID 7333741
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