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International Society of Sports Nutrition position stand: Nutrient timing

Chad Kerksick12*, Travis Harvey3, Jeff Stout1, Bill Campbell4, Colin Wilborn5, Richard Kreider6, Doug Kalman7, Tim Ziegenfuss8, Hector Lopez9, Jamie Landis10, John L Ivy11 and Jose Antonio12

Author Affiliations

1 Department of Health and Exercise Science, University of Oklahoma, Norman, OK 73019, USA

2 Endocrinology and Diabetes Section, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA

3 Center for Physical Development Excellence, Department of Physical Education, United States Military Academy, 727 Brewerton Road, West Point, NY 10996, USA

4 School of Physical Education & Exercise Science, University of South Florida, Tampa, FL 33620, USA

5 Exercise & Sport Science Department, University of Mary-Hardin Baylor, Belton, TX 76513, USA

6 Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843, USA

7 Nutrition/Endocrinology Division, Miami Research Associates, Miami, FL 33143, USA

8 Division of Sports Nutrition and Exercise Science, The Center for Applied Health Sciences, Fairlawn, OH 44333, USA

9 Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA

10 Department of Biology, Lakeland Community College, Kirtland, OH 44094, USA

11 Department of Kinesiology & Health Education, University of Texas, Austin, TX 78712, USA

12 Farquhar College of Arts and Sciences, Nova Southeastern University, Fort Lauderdale, FL 33314, USA

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Journal of the International Society of Sports Nutrition 2008, 5:17  doi:10.1186/1550-2783-5-17

Published: 3 October 2008

Abstract

Position Statement: The position of the Society regarding nutrient timing and the intake of carbohydrates, proteins, and fats in reference to healthy, exercising individuals is summarized by the following eight points: 1.) Maximal endogenous glycogen stores are best promoted by following a high-glycemic, high-carbohydrate (CHO) diet (600 – 1000 grams CHO or ~8 – 10 g CHO/kg/d), and ingestion of free amino acids and protein (PRO) alone or in combination with CHO before resistance exercise can maximally stimulate protein synthesis. 2.) During exercise, CHO should be consumed at a rate of 30 – 60 grams of CHO/hour in a 6 – 8% CHO solution (8 – 16 fluid ounces) every 10 – 15 minutes. Adding PRO to create a CHO:PRO ratio of 3 – 4:1 may increase endurance performance and maximally promotes glycogen re-synthesis during acute and subsequent bouts of endurance exercise. 3.) Ingesting CHO alone or in combination with PRO during resistance exercise increases muscle glycogen, offsets muscle damage, and facilitates greater training adaptations after either acute or prolonged periods of supplementation with resistance training. 4.) Post-exercise (within 30 minutes) consumption of CHO at high dosages (8 – 10 g CHO/kg/day) have been shown to stimulate muscle glycogen re-synthesis, while adding PRO (0.2 g – 0.5 g PRO/kg/day) to CHO at a ratio of 3 – 4:1 (CHO: PRO) may further enhance glycogen re-synthesis. 5.) Post-exercise ingestion (immediately to 3 h post) of amino acids, primarily essential amino acids, has been shown to stimulate robust increases in muscle protein synthesis, while the addition of CHO may stimulate even greater levels of protein synthesis. Additionally, pre-exercise consumption of a CHO + PRO supplement may result in peak levels of protein synthesis. 6.) During consistent, prolonged resistance training, post-exercise consumption of varying doses of CHO + PRO supplements in varying dosages have been shown to stimulate improvements in strength and body composition when compared to control or placebo conditions. 7.) The addition of creatine (Cr) (0.1 g Cr/kg/day) to a CHO + PRO supplement may facilitate even greater adaptations to resistance training. 8.) Nutrient timing incorporates the use of methodical planning and eating of whole foods, nutrients extracted from food, and other sources. The timing of the energy intake and the ratio of certain ingested macronutrients are likely the attributes which allow for enhanced recovery and tissue repair following high-volume exercise, augmented muscle protein synthesis, and improved mood states when compared with unplanned or traditional strategies of nutrient intake.