Effekten av högt respektive lågt kolhydratintag på prestation vid uthållighetsträning
Sahlgrenska Academy at University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: The effect of a high versus low carbohydrate intake on endurance performanceAuthor: Emma Andersson and Josefine DahlqvistSupervisor: Fredrik BertzExaminer: Frode SlindeProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 22, 2013BackgroundCarbohydrates play a significant role in the human metabolism, especially during training. Manystudies have investigated the effects on different carbohydrate intakes on training performance. Thescientific researchers have met a consensus in the fact that a higher intake of carbohydratescompared to a lower carbohydrate intake improves athletic performance. Lately, the increasedinterest in low carbohydrate diets has despite these recommendations gained followers globally.ObjectiveTo determine if a higher carbohydrate intake results in a better endurance performance, comparedto a lower carbohydrate intake, for adult males and females, measured as time to exhaustion, totaldistance covered and power output/cadence. To be able to give nutrition recommendations toendurance athletes based on the current scientific evidence and identify if there is need for furtherresearch in this area.Search strategyThe databases used for the literature search were PubMed and Scopus. The search words that wereused were carbohydrates, performance and endurance, among others.Selection criteriaInclusion criteria: studies on adults over 18 years, randomized controlled trials, human studies, andnutrition interventions lasting at least one day. Exclusion criteria: studies written in other languagesthan English or Swedish, other current nutrition intervention, studies made solely on intake of aglucose solution ingested before or during exercise, diets with carbohydrate contents between30 E% and 60 E%, and diets with carbohydrate contents between 3 g/kg bodyweight and 6 g/kgbodyweight.Data collection and analysisThere were four studies included in this review article. A template from Swedish SBU was used toexamine the articles design, population and results. Another grading template was used to determinethe scientific evidence of each relevant outcome measure.Main resultsThere was a significant difference in improved endurance performance after intake of a highcarbohydrate diet compared to a diet low in carbohydrates in three of the studies. One of the studiesshowed no significant difference between the two diets. All four studies where given the evidencegrading ?moderate? and the scientific evidence for the selected measure outcomes were each given alow evidence (++).ConclusionsIt seems that a diet high in carbohydrates compared to a diet low in carbohydrates improvesendurance performance. The evidence is however low and more research is needed to furtherconfirm these results.