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A Common Sense Approach To Talking with Your Athletes About Supplements Gregory Biren, PhD, CSCS Rowan University Health and Exercise Science Department [email protected] http://users.rowan.edu/~biren/ Supplements 1994 “Dietary Supplement Health & Education Act” (DSHEA) – enabled consumers to gain unobstructed access –established 1st legal definition FDA does regulate supplements, however limited control – Center for Food Safety & Applied Nutrition (CFSAN) oversees FDA’s activities on supplements – Office of Dietary Supplements (NIH) – drugs must undergo clinical testing & report findings to FDA – supplements manufacturers must notify FDA; but NOT required to test DSHEA May NOT be represented as conventional food (must be labeled as supplement) Requires some evidence that product is safe & effective Burden of proof for showing safety falls on FDA NOT manufacturer – FDA must PROVE that supplement taken under recommended doses is unsafe (if someone takes in excess NOT manufacturers problem) Literature to promote product – can’t be misleading?? – “statement has not been approved by FDA” – product is not intended to diagnose, treat, cure or prevent disease Statements of Nutritional Support Supplements are allowed to carry claim statements in 1 of 4 categories 1. Claim of benefit relating to a classical nutrient deficiency disease (folic acid & neural tube defects) 2. Claim describing role of nutrient & effect on structure or function of body a. can’t say “prevents osteoporosis” but can say important in developing bone strength 3. Mechanism by which nutrient acts to maintain structure & function a. vitamin D ↑ absorption of Ca++ at small intestine & ↓ excretion at kidneys 4. Claim describing general well being from consuming nutrient (ie elevates mood states) “Supplement” Defined? Any product (other Vitamins than tobacco) Minerals intended to Herbs/Botanicals supplement the diet that contains one of Amino acid more of the following Enzymes ingredients: Metabolite or combination of these ingredients Ergogenic Aids ??? Ergogenic “ergo”= work, “genic”= produce Ergogenic Aids - enhancing performance 1. Pharmacological – pertaining to drugs 2. Chemical – caffeine, phosphate, growth hormone 3. Nutritional – vitamins, minerals, carbohydrates They can work, but some at a cost!!!! Approach to Supplements 1. NOTHING can take place of a quality nutritional & exercise program 2. Ask why they want to use supplement • What do they know about it? 3. Evaluate their current nutritional program • get them to correct this first •“FOOD FIRST” 4. Educate them on what research says • show them how research can be manipulated • talk about side effects 5. Ask them how long do they plan to take this supplement • What are they going to do when they stop? 6. Be careful about cause and effect 7. Now they can make their own decision Protein Structurally similar to carbs & lipids (carbon, oxygen, & hydrogen), also contain nitrogen – amine group (N), carboxyl group & side chain Amino acids (basic building blocks) – 20 a.a., 8 essential Deamination – removal of nitrogen group in order to use protein for energy, carb or fat formation Transamination allows a.a. to be converted to other a.a. Functions: Enzymes, Antibodies, Transport molecules, Fluid & acid base balance, Hormones, Oxygen carriers, Structural proteins Energy ?? – **we DON’T store protein, use it or convert it ProteinsProteins Complete – contains all essential A.A. – meat, dairy, fish, poultry, eggs Getting all essential A.A. not problem for those regularly eating complete proteins, but.. Incomplete proteins (grains, greens, legumes) Complementary Proteins Quality of Protein RDA = .8 grams/kg: covers 98% of population Includes 25% reserve for differences vegetarian needs higher – must also make sure protein is complete or complementary What about athletes? 1.2-1.8 grams/kg >2 grams/kg waste ProteinProtein SupplementsSupplements WheyWhey CaseinCasein ColostrumColostrum AminoAmino AcidsAcids LeucineLeucine GlutamineGlutamine ArginineArginine AlanineAlanine BranchBranch ChainChain AminoAmino AcidsAcids (BCAA)(BCAA) ArginineArginine Non-essential amino acid – suggested that body synthesis is insufficient for optimal health (semi-essential) – “L” - natural –“D” -synthetic Involved in reactions producing vasodilation & CV function by being converted to nitrous oxide (NO) Associated with ↓ symptoms of CAD, slow atherosclerosis – inhibits adherence of cells to vessel walls Due to conversion to nitrous oxide, exercisers supplement for the “pump” & to drive nutrients into muscle cells L-Carnitine An amino acid made in liver & kidneys from other amino acids – found in meat & dairy products Transfers fatty acids into mitochondria May help inhibit pyruvate conversion to lactic acid Claims – ↑ endurance – ↑ fat metabolism – Lower cholesterol & triglyceride levels Research on L-Carnitine Research - patients with muscle weakness, kidney disease, on restricted diet may show benefit – this is due to loss of carnitine loss in kidneys May help vegetarians/diets low in animal proteins who are deficient in carnitine in diet Healthy populations show NO benefit from supplementation if diet is adequate No research indicates potential side effects Creatine N+ containing organic compound made in body from A.A. metabolism 95% is found in muscle Found in meat, poultry & fish – Body requires ~2g/day, more if active – body synthesizes 1 g/day (liver) – 1 gram/ 8 ounces of meat – vegetarians could be deficient Supplemental form creatine monohydrate Vital role in cellular energy production – Stored as phospho-creatine Claims – ↑ energy, ↑ lean tissue, ↑ muscle strength Creatine Claims backed up by research – >20 studies show improvement in HIGH intensity, short term activities (anaerobic sports) – Probably nothing for low intensity longer duration Benefits: – faster ATP turnover; delay PC depletion – delay dependence on glycolysis – facilitate recovery from repeated bouts of intense exercise Body mass ↑ 1-5 lbs** (regardless of testosterone concentration) Does ↑ weight come from muscle tissue or water retention? –probably combination Creatine Loading “Loading phase” 20-30 grams daily for 5-7 days – PC levels rise, but remain high (↑ 30%) for only a few days, so.. Maintenance phase 2-5 g daily – **in addition to diet w/o maintenance phase creatine levels are normal by 35 days Alternative Loading – 3-5 g/day for 28 days gives same creatine levels Caffeine Most common stimulant in the world Claims – ↑ energy – Improves athletic performance –Promotes weight loss – ↑ metabolic rate ↑ release of epinephrine – glycolysis, lipolysis, CNS stimulant – ↑ release of Ca++ from SR, ↑ contractility Controlled/restricted drug in athletic competition – IOC & NCAA restrict use – 2-3 cups OK Caffeine Cycling 80% max power to exhaustion Beyond 5 mg/kg no > effect – 5 mg/kg won’t reach IOC doping limits Proposed Mechanisms for Ergogenic Action Acts directly on adipose tissue – acts indirectly on adipose tissue by stimulating epinephrine release – ↑ plasma fatty acids, ↑ fat oxidation Spares liver & muscle glycogen Produces analgesic effect on CNS ↑ motor-neuronal excitability (↑ motor unit recruitment – ↑ release of Ca++ & ↑ sensitivity of actin & myosin to Ca++ –May ↑ submax muscle contractions, does NOT ↑ max muscle contractions More on Caffeine People develop tolerance to caffeine – more needed for same effect Caffeine in coffee has < effect than caffeine pills If using as ergogenic aid for event, need to abstain 4-6 days prior Can produce restlessness, headaches, insomnia, nervous irritability, ↑ H.R. & BP Acts as a diuretic (dehydration) Chromium Trace mineral found in broccoli, wheat germ, nuts, egg yolks, apples (food processing removes chromium) Cofactor to ↑ insulin function Deficiencies: – ↓ insulin sensitivity (type 2 diabetes) Estimated 90% of adults consume < RDA, urinary chromium excretion ↑ with exercise Claims: – lower blood sugar & ↑ insulin sensitivity – reduces body fat & ↑ lean mass – suppresses appetite – ↓ cholesterol & triglyceride levels Chromium Supplementation & Resistance Training B-Hydroxy B-Methylbutyrate (HMB) Metabolite from breakdown of leucine (amino acid) – Small amount found in protein rich foods milk & fish Claims – ↓ protein loss by inhibiting protein catabolism –muscle building –fat reducing Target resistance training athletes B-Hydroxy B-Methylbutyrate (HMB) Research – HMB group showed blunted rise in proteolysis – Results seen within several wks. – By last week of study fat free mass changes were NOT sig. Used by NASA to prevent muscle wasting in astronauts No side affects have been seen at this time Dehydroepiandrosterone (DHEA) Steroid hormone synthesized in adrenal cortex – precursor to testosterone, estrogen & cortisol –Levels ↓ with aging Claims – ↑ muscle mass, ↓ fat mass –Anti-aging – Stimulates sex drive Dehydroepiandrosterone (DHEA) Little is know about long term effects & dosages Has been shown to ↑ testosterone level, muscle mass, promote feelings of well-being, & immune function, in 40-70 yr. – Results NOT substantiated in younger healthy populations Concerns (no research) about altered hormone profiles, liver abnormalities, ↑ risk of prostate & breast cancer, ↑ testosterone levels in females, gynecomastia in men (↑ estrogen) – side effects may not be noticeable for years Recent study showed dramatic differences in amount stated on label & actual (150%-0%) only 50% had proper amounts Androstenedione Precursor (pre-hormone) of testosterone & estrogen b/c found naturally in meat can be called a “nutritional