| Autor: |
Buga A; Department of Human Sciences, The Ohio State University, Columbus, OH 43210, USA., Welton GL; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Scott KE; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Atwell AD; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Haley SJ; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Esbenshade NJ; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Abraham J; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Buxton JD; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Ault DL; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA., Raabe AS; Department of Human Ecology, Youngstown State University, Youngstown, OH 44555, USA., Noakes TD; Department of Applied Design, Cape Peninsula University of Technology, Cape Town 8000, South Africa., Hyde PN; Department of Kinesiology, University of Northern Georgia, Dahlonega, GA 30597, USA., Volek JS; Department of Human Sciences, The Ohio State University, Columbus, OH 43210, USA., Prins PJ; Department of Exercise Science, Grove City College, Grove City, PA 16127, USA. |
| Abstrakt: |
A growing number of endurance athletes have considered switching from a traditional high-carbohydrate/low-fat (HCLF) to a low-carbohydrate/high-fat (LCHF) eating pattern for health and performance reasons. However, few studies have examined how LCHF diets affect blood lipid profiles in highly-trained runners. In a randomized and counterbalanced, cross-over design, athletes (n = 7 men; VO2max: 61.9 ± 6.1 mL/kg/min) completed six weeks of two, ad libitum, LCHF (6/69/25% en carbohydrate/fat/protein) and HCLF (57/28/15% en carbohydrate/fat/protein) diets, separated by a two-week washout. Plasma was collected on days 4, 14, 28, and 42 during each condition and analyzed for: triglycerides (TG), LDL-C, HDL-C, total cholesterol (TC), VLDL, fasting glucose, and glycated hemoglobin (HbA1c). Capillary blood beta-hydroxybutyrate (BHB) was monitored during LCHF as a measure of ketosis. LCHF lowered plasma TG, VLDL, and TG/HDL-C (all p < 0.01). LCHF increased plasma TC, LDL-C, HDL-C, and TC/HDL-C (all p < 0.05). Plasma glucose and HbA1c were unaffected. Capillary BHB was modestly elevated throughout the LCHF condition (0.5 ± 0.05 mmol/L). Healthy, well-trained, normocholesterolemic runners consuming a LCHF diet demonstrated elevated circulating LDL-C and HDL-C concentrations, while concomitantly decreasing TG, VLDL, and TG/HDL-C ratio. The underlying mechanisms and implications of these adaptive responses in cholesterol should be explored. |
