3/2/2015. Categories of dietary supplements. Athletes use supplements because

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1 SPORTS NUTRITION: CONVENTIONAL FOOD VS SUPPLEMENTS VS SPORT FOODS GIVE YOURSELF THE OPPORTUNITY TO REACH YOUR HIGHEST POTENTIAL UMBC DIETITIAN : SARENA C GLENN RD, LDN, MS Categories of dietary supplements Promote tissue growth, repair, adaptation to training Promote fat loss Enhance energy supply Promote immune function and resistance to illness/infection Promote joint health Promote general health Sports drinks, energy bars etc Central nervous system stimulant effects Maughan et al. (2013) Dietary Supplements for athletes: Emerging trends and recurring themes. Journal of Sports Sciences. Vol 29 Issue 8 Athletes use supplements because Aids in recovery from training 71% Health 52% Improve performance 46% Prevent or treat illness 40% Compensate for poor diet 29% Maughan et al. (2013) Dietary Supplements for athletes: Emerging trends and recurring themes. Journal of Sports Sciences. Vol 29 Issue 8 1

2 MAIN BELIEF BY MANY.. If a little is good, then more must be better McArdle et al. (2013). Sports and Exercise Nutrition p. 237 Vitamin : FACTS Vitamins are metabolic catalysts that regulate biochemical reactions in the body. Clark, N Nancy Clark s Sports Nutrition Guidebook Fifth Edition. P. 215 & Exercise & Sports Nutrition The Ultimate Training and Nutrition Guide to Optimal Health, Fitness and Performance. Kreider, R.B. et al Vitamin Supplement Truth : Fat Soluble RDA = Recommend Daily Amount Vitamin Body Function Female RDA A Vision 700 µg 900 µg D E Bone Growth, Enhance 5 µg (< Ca+ absorption 50yrs) During exercise improving or maintaining oxygen delivery Male RDA 5 µg (< 50yrs) K Blood Clotting 90 µg 120 µg Studies of HIGH dosages No studies reveal enhancement in athletic performance. Does not enhance performance More studies are needed Female improve bone formation and resorption, not athletic performance 2

3 Vitamin Supplement Truth : Water Soluble RDA = Recommend Daily Amount Vitamin Body Function Female RDA Male RDA Studies of HIGH dosages Thiamine (B1) Improve anaerobic threshold 1.1 mg 1.2 mg No effect on athletes exercise capacity with normal intakes Energy metabolism. Theory : enhance energy availability No effect on athletes exercise capacity with Riboflavin (B2) during exercise 1.1 mg 1.3normal intakes Niacin (B3) Energy metabolism. Theory : increase fatty acids during exercise, improve energy availability during exercise 14 mg 16 mg Supplementation decreases exercise capacity by discouraging fatty acids Kreider et al. Exercise & Sports Nutrition 2009 AND McArdle et al. Sports and Exercise Nutrition Fourth Edition 2013 Vitamin Supplement Truth : Water Soluble Vitamin Body Function Female RDA Male RDA Marketed as supplement to improve muscle mass, strength and aerobic power. Calm effect linked to improved mental Pyridoxine (B6) strength 1.3 mg 1.3 mg Cyanobalamin (B12) Protein synthesis. Theory: increase muscle mass, decrease anxiety, increase oxygen carrying capacity of blood 2.4 µg 2.4 µg Studies of HIGH dosages Failed to improve aerobic capacity and lactic acid accumulation No effect has been reported athletes except for pistol shooters. Folic Acid (Folate) Improve oxygen delivery to muscles during exercise 400 µg 400 µg Does not improve athletic performance Vitamin Supplement Truth : Water Soluble Vitamin Body Function Female RDA Male RDA Studies of HIGH dosages May benefit aerobic and No improvements in athletic performance. Decrease in lactic acid without improving Pantothenic Acid oxygen energy systems 5 mg 5 mg performance Beta carotene Vitamin C Minimize exercise induced cell and muscle damage 3-20 mg 3-20 mg Iron absorption. Theory: Improve metabolism during exercise. May enhance immunity 75 mg 90 mg Improve athletes tolerance of training over time, unclear if it will improve performance Does not improve performance. Some evidence: may decrease risk of getting a cold after intense exercise 3

4 Minerals Provide structure to forming bones and teeth. Maintain normal heart function, muscle integrity, and acid base balance Regulate metabolism which controls cellular activity Fink et al Practical Applications in Sports Nutrition. Ch 7 Minerals AND McArdle et al Sports and Exercise Nutrition. Ch 2 The Micronutrients and Water Nature of Minerals Minerals eg. Chromium Minerals eg. Magnesium Selenium compliments Vitamin E function Mineral Supplement Truth RDA = Recommend Daily Amount Mineral Marketing to Athletes Female RDA Male RDA Studies of HIGH dosages Boron Chromium Iron May benefit aerobic and oxygen energy systems none none Increase lean body mass and decrease body fat levels 25 µg 35 µg Increase aerobic performance; mg 8 mg No evidence that during resistance training muscle growth is promoted Recent well controlled studies indicate no improvement in lean body mass or decrease of body fat Athletes who are iron depleted (Anemia) show increase in aerobic performance 4

5 RDA = Recommend Daily Amount Mineral Supplement Truth Mineral Marketing to Athletes Female RDA Male RDA Studies of HIGH dosages Sodium Helps regulate fluid balance, nerve transmission, acid base balance. Excessive decrease can cause cramping & hyponatremia 1.5 grams 1.5 grams Intense training induces greater losses of sodium thru sweat. Increasing salt availability maintains fluid balance. Potassium Magnesium Regulate fluid balance, nerve transmission, acid base balance. Excessive increase or decrease cause cramping. 25 µg 35 µg Improve energy metabolism; enzyme involved in protein synthesis and ATP mg mg Unclear if supplementation would decrease incidence of cramping. Does not affect exercise performance in athletes unless there is a deficiency. Calcium Bottom Line: If you are taking a supplement, you should still try to include the food sources of the vitamin you are supplementing. Common Sources of Vitamins & Minerals Reminder that all vitamins and minerals needed can be found in whole food. 5

6 Vitamins and Mineral Supplements Body can not make on it s own No significant amount of scientific evidenced shows that excessive amounts of vitamins or minerals will improve your performance. Training does not increase your vitamin and mineral needs Maximize your performance by eating quality foods. The more you exercise, the more you eat, thus you are already eating more vitamins and minerals Biologic functions of vitamins in the body (McArdle, 2013) Clark, N Nancy Clark s Sports Nutrition Guidebook Fifth Edition AND McArdle et al Sports and Exercise Nutrition. Know the Facts Valid proof of effectiveness of supplements is often lacking Review research : 3 out of 74 sports performance studies were in good quality with low bias (Heneghan et al as cited by Clark, 2014) Supplements are not closely regulated Natural does not mean safe Know which substances are banned Only recommended supplements : Multivitamins Whole foods provide the majority of vitamin and mineral needs to optimize performance. Maughan et al. (2013) Dietary Supplements for athletes: Emerging trends and recurring themes. Journal of Sports Sciences. Vol 29 Issue 8 Heneghan et al. (2012) The evidence underpinning sports performance products: A systematic assessment. BMJ Open 2012 Muth. N.D Sports Nutrition for Health Professionals. Chapter 2. Clark, N Nancy Clark s Sports Nutrition Guidebook. P 213 When a multivitamin may be warranted Lactose Intolerant Vegan Indoor Athlete Allergic to Certain Foods MULTIVITAMIN Clark, N Nancy Clark s Sports Nutrition Guide. Supplements, Performance Enhancers and Engineered Sports Foods 6

7 Other supplementations Performance Enhancing Supplements False Claims Contaminated Muscle Builders Best muscle exercise is resistance exercise that fatigues your muscles Endurance Enhancers Must OPTIMIZE diet with FOOD All nutrients food are linked to immunity. Carbohydrates: immunity is enhanced when consumed BEFORE, DURING and AFTER training which reduces stress response Commercial Sports Foods Created more for convenience than necessity Daily bottle of sports beverage at $2.00 per day = $50-60/month vs homemade sports drink (See Hydration Lecture) Commercial sports drinks only offer carbohydrates from one source Offer carbohydrate and protein with no fat. Bottom Line: Top performance comes from a foundation diet consisting of whole foods. Clark, N Nancy Clark s Sports Nutrition Guide. Supplements, Performance Enhancers and Engineered Sports Foods NCAA Nutritional/Dietary Warning Before consuming any nutritional/dietary supplement product, review the product with the appropriate or designated athletics department staff! Dietary supplements are not well regulated and may cause a positive drug test result. Student-athletes have tested positive and lost their eligibility using dietary supplements. Many dietary supplements are contaminated with banned drugs not listed on the label. Any product containing a dietary supplement ingredient is taken at your own risk. Note to Student-Athletes: There is no complete list of banned substances. Do not rely on this list to rule out any supplement ingredient. Check with your athletics department staff prior to using a supplement. Website NCAA Banned Drugs For more info go to or 7

8 More than 50 sources of sports nutrition and media..check out What do I buy at the grocery store to improve my performance? When should I drink a protein supplement vs. eating a sandwich? How should I eat to heal my injury? Log into MyUMBC Go to UMBC Dining Services page Click on Retrievers: Sports Nutrition folder Does caffeine improve my performance? THANK YOU! Questions Umbcrd@umbc.edu 8