Sports Nutrition: Fundamentals


Proper nutrition is the foundation of any good strength and conditioning program. Everyone agrees with the previous statement, however not all experts agree as to what entails "proper nutrition". With all the gurus and gimmicks out there it's extremely difficult to determine what sound nutritional practices are. The guidelines contained on this page are designed to support a program of intense weight training and high intensity exercise based on research, not magazines, blogs, or independent commercial companies. Hyperlinks are provided for all sources and you are encouraged to read the supporting publications and make your own decisions.

The focus of this post is on general dietary practices to support the type of physical training of the Strength Group: high intensity conditioning and weightlifting. Future posts will expand on selected relevant topics in sports nutrition.

The basis of dietary intake should be whole foods which are as minimally processed as possible. This is the concept of food synergy, which is the idea that natural whole foods contain nutrients in combinations that are more beneficial for health than engineered foods or an isolated nutrient supplement (1, 4, 10). If you don't recognize an ingredient, then that food is most likely processed and contains unwanted additives and calories with relatively few nutrients. Desirable whole foods to support training include non-starchy vegetables, fruits, starches and starchy vegetables (such as whole grains, potatoes, rice, and corn), lean meat and seafood, and low/non-fat dairy.

Protein Power

Dietary protein provides amino acids for your body which are used in all bodily structures including muscle, connective tissues, and organs. Amino acids also form many important compounds like enzymes and hormones which are important for your metabolism and performance. Daily dietary protein requirements differ based on many factors including lean body mass and activity levels (1, 2, 9). Consuming a variety of protein sources is important to ensure adequate nutrition (1, 2, 10). Consuming dietary protein above recommended levels has not been shown to offer any benefit in terms of lean mass gain or performance (1, 9). In fact, over consumption of protein may actually impair performance (3, 7, 8). Athletes conducting regular intense training are recommended to consume between 1.6 to 2.0 grams of protein per kilogram of body weight (roughly 0.7 to 0.9 grams of protein per pounds of body weight) (1, 2, 9). Recommended primary sources of protein are animal, seafood, and low/non-fat dairy products, as these are complete protein sources which provide all essential amino acids (2). Include a lean source of protein in each meal or snack to meet your daily total protein requirement.

Carbs Schmarbs

High intensity exercise preferentially burns carbohydrate for fuel, while exercise at a lower intensity preferentially burns fat (1, 5, 6). As the focus of this program is high intensity exercise, carbohydrates provide the primary fuel for exercise, and as such, should form the basis of your diet. There are many different types of carbohydrates, but for our purposes here we're concerned with three major types, all plant life: non-starchy vegetables, grains/starchy vegetables, and fruits. We want to include a variety of these sources of carbs at each meal or snack. Eat an unrestricted amount of non-starchy vegetables at each meal. Consume one or two servings of fruit at each meal. Round out your carbs with a minimally processed significant carb source such as whole wheat pasta, sweet potatoes, potatoes, whole grain rice, corn, etc. Daily guidelines for carbohydrate intake to support an intense exercise regime is between 6 and 10 grams of carbohydrate per kilogram of bodyweight (between 2.7 to 4.5 grams of carbohydrate per pound of bodyweight) (1, 6).

Fats

Fats are essential to your health and well-being. They provide energy while at rest or during low-intensity activities, transport fat soluble vitamins, are involved in hormone production, provide insolation and protection, provide a feeling of satiety, and most importantly give your food flavor. Fats are very energy dense (roughly 9 Calories per gram compared to about 4 Calories per gram for carbohydrate and protein). While certain lifestyles may benefit from the focused consumption of fat sources, a program focusing on high intensity exercise is not one of those lifestyles (1, 5, 6). Increasing the fat content of your diet will result in a reduction in either carbohydrate content, protein content, or both; this will impair your performance and recovery (3, 7, 8). The goal is roughly 20% to 30% of daily Calories from fat sources (1, 10), which can be accomplished by focusing on meeting goals for protein and carbohydrate consumption and using fats primarily to cook or garnish your foods. Examples include roasting your vegetables in olive oil, creating an avocado dressing for your chicken salad, or crushing up some nuts to top your yogurt.

Putting it All Together

Simple meal construction that will support training involves selecting one or more quality lean protein sources, adding copious amounts of non-starchy vegetables, one to two servings of fruits, and an appropriate amount of starches or starchy vegetables to meet your daily carbohydrate goals. Use fats in preparation or as a garnish. Divide your recommended intake up amongst your meals for the day, eating every 4 to 6 hours to prevent hunger and optimize recovery and performance.

Sources

1. Butterfield, G., Manore, M., & Barr, S. (2000). Nutrition and athletic performance: American College of Sports Medicine, American Dietetic Association, and Dietitians of Canada joint position statement. Medicine and Science in Sports and Exercise, 32(12), 2130-2145. Available from: http://journals.lww.com/acsm-msse/Fulltext/2009/03000/Nutrition_and_Athletic_Performance.27.aspx

2. Campbell, B., Kreider, R. B., Ziegenfuss, T., La Bounty, P., Roberts, M., Burke, D., …Antonio, J. (2007). International society of sports nutrition position stand: protein and exercise. Journal of the International Society of Sports Nutrition, 4(8), 1-7. Available from: http://www.biomedcentral.com/content/pdf/1550-2783-4-8.pdf

3. Fleming, J., Sharman, M. J., Avery, N. G., Love, D. M., Gomez, A. L., Sheett, T. P., …Volek, J. S. (2003). Endurance capacity and high-intensity exercise performance responses to a high-fat diet. International Journal of Sports Nutrition and Exercise Metabolism, 13, 466-478. Available from: http://journals.humankinetics.com/AcuCustom/Sitename/Documents/DocumentItem/2621.pdf

4. Jacobs, D., Gross, M., & Tapsell, L. (2009). Food synergy: an operational concept for understanding nutrition. American Journal of Clinical Nutrition, 89(suppl), 1543S-8S. Available from: http://ajcn.nutrition.org/content/89/5/1543S.long


6. Kerksick, C., Harvey, T., Stout, J., Campbell, B., Wilborn, C., Kreider, R., …Antonio, J. (2008). International society of sports nutrition position stand: nutrient timing. Journal of the International Society of Sports Nutrition, 5(17), 1-12. Available from: http://www.biomedcentral.com/content/pdf/1550-2783-5-17.pdfJournal

7. Langfort, J., Zarzeczny, R., Pils, W., Nazar, K., & Kaciuba-Uscitko. (1997). The effect of a low-carbohydrate diet on performance, hormonal and metabolic responses to a 30-s bout of supramaximal exercise. European Journal of Applied Physiology, 76, 128-133. Available from: http://www.researchgate.net/profile/Ryszard_Zarzeczny/publication/13947246_The_effect_of_a_low-carbohydrate_diet_on_performance_hormonal_and_metabolic_responses_to_a_30-s_bout_of_supramaximal_exercise/links/54d389c40cf2501791823f99.pdf

8. Maughan, R. J., Greenhaff, P. L., Leiper, J. B., Ball, D., Lambert, C. P.,& Gleeson, M. (1997). Diet composition and the performance of high-intensity exercise. Journal of Sports Sciences, 15, 265-275. Available from: www.researchgate.net/profile/Derek_Ball2/publication/13986240_Diet_composition_and_the_performance_of_high-intensity_exercise/links/0912f50fff4fa93751000000.pdf

9. Phillips, S. (2004). Protein requirements and supplementation in strength sports. Nutrition, 20, 689-695. Available from: http://www.clalit.co.il/he/lifestyle/sport/fitness/Documents/2004_ProteinRequirementsandSupplementationinStrengthSports.pdf

10. U. S. Department of Agriculture and U. S. Department of Health and Human Services. Dietary Guidelines for Americans 2010. 7th Edition, Washington, D. C.: U. S. Government Printing Office, December 2010. Available from: http://www.health.gov/dietaryguidelines/dga2010/DietaryGuidelines2010.pdf

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