Formula for Success

Nutrition for Distance Runners Objectives:     Understand how nutrition impacts sport and exercise performance Learn specific carbohydrate, protein, fat, and fluid requirements Be aware of the role of supplements and ergogenic aids Know how to find credible sports nutrition information and resources Formula for Success = Natural Talent + Required Training + Proper Attitude + Foundation (Nutrition and Hydration) Energy Systems: What is Energy? Energy is a measurement of work or heat. One calorie (kcal) is the amount of heat required to raise the temperature of 1 kilogram of water by 1°C at one atmospheric pressure. In terms of nutrition, one kcal is the common unit used to express the energy-producing potential of food as it is metabolized by the body. Characteristics of the 3 Major Energy Systems System Anaerobic (without oxygen via PC) Anaerobic (without oxygen via glycolysis) Fuel Phosphocreatine Glycogen (CHO) Oxygen required No No Speed of Energy Provision Fastest (seconds) Fast (~4 minutes) Relative energy (ATP) produced Little; limited Little; limited Aerobic (with oxygen) Glycogen, fats Yes Slow (>4 minutes) Much; unlimited (assuming adequate provision of energy substrate) Created by WellCorp, a Nationwide Better Health company, 2007 1 Nutrition for Distance Runners Energy Sources: Food CHO and Protein = 4 kcal per gram; Fat = 9 kcal per gram (e.g. one medium apple has 15 gm CHO and 60 kcal) Energy Stored: Body Carbohydrate:  Circulating glucose = 62 kcal  Glycogen 1) Liver = 110 gm or 440 kcal 2) Muscle 250 gm or 1,000 kcal   Note that the minimal amount of carbohydrate required is determined by the brain’s requirement for glucose. The brain is the only true carbohydrate-dependent organ. The requirement for glucose has been reported to be approximately 110 to 140 g/d in adults. In general running burns 7.8 kcal/hr/kg body weight. Therefore, a person weighing 60 kg (132lb) would burn approximately 2,100 calories after running for 4.5 hours. Fat (Adipose tissue):  Subcutaneous fat (skinfold areas)  Visceral fat (surrounds the organs)  Serum (triglycerides)  Intra-muscular *Energy utilization depends on percentage of total body fat. An average person weighing 65 kg (143#) and has 12% body fat can store approximately 7,800 gm of fat or 70,200 kcal. Therefore, if this person required 2200 kcal daily they could survive off of their fat stores for approximately 31 days (1 month). Protein:  Amino acid pools, 25% of all the protein in the body is ‘turned over’ daily 1) Central amino acid pool is in the plasma 2) Also a small pool in intracellular muscle  Therefore, protein plays a very small role as use for fuel because of its high demand to act as a catalyst to carry out enzymatic reactions. Created by WellCorp, a Nationwide Better Health company, 2007 2 Nutrition for Distance Runners Macronutrients: A nutrient required by the body in large quantities. Carbohydrate (CHO): most common source of energy Best Sources (Everyday foods):           100% whole wheat or rye bread, pita, tortilla, bagels, English muffins, and crackers Bran, corn, oat, and wheat based dry cereals, granola, and granola bars Cooked cereal (oatmeal and grits) Baked Potatoes (w/ skin) Rice and pasta Barley and quinoa Popcorn Fruits (fresh, frozen, dried, 100% fruit juice) Yogurt, soy, rice, and skim or 1% cow’s milk Sports drinks, bars, and gels Requirements: 60-65% of your daily caloric intake General guidelines are: --Average American adult: 3-5g/kg --Exercise less than an hour/d: 6g/kg --Intense *exercise: 1-4 hours/d: 9-10 g/kg --Intense *exercise >4 hours/d: 11-12 g/kg *Intense exercise defined as >70% of VO2 max Example: If you weigh 60 kg (132#) and exercise intensely for 2.5 hours/day, you would need approximately 540-600g/d of carbohydrates. Hot Topics: 1. Glycemic Index (GI): Blood glucose (response) of a food as compared to a standard (50 gm of glucose = GI 100). Note that 1 slice of white bread as the standard is now obsolete. See GI handout. Created by WellCorp, a Nationwide Better Health company, 2007 3 Nutrition for Distance Runners 2. Rebound Hypoglycemia: A phenomenon that does occur in the first 10-20 minutes of activity after a pre-exercise ingestion of CHO but does not negatively impact athletic performance that lasts 60 minutes or longer. The theory is that if exercise is commenced when insulin is high (from pre-exercise CHO load, especially if it is a high GI food) the metabolic response is a quick decline in blood glucose. 3. Blood sugar maintenance: Timing of meals/snacks is critical! Pre-event emphasis: o Provide energy, predominately CHO, but also easily digestible. Avoid highly fibrous foods (e.g. beans, nuts, seeds, bran). o Timing: 3-4 hours before event begins need designated meal amount, 45-60 minutes before a run you need approximately 75 gm of a mixed CHO source if performing for >60 minutes. o If the event is < 2 hours away, consider a liquid or blenderized meal. During exercise: 16 gm CHO per hour (note: 8 z of Gatorade contains 14 gm CHO, one Cliff® shot gel contains 25 gm CHO) Optimizing muscle glycogen post exercise: o Must induce a rise in insulin by 30 minutes post-exercise to induce the greatest uptake of glucose and amino acids into muscle. o Research data supports that the combination of protein and CHO post-exercise has a 5-fold increase in uptake. o Use a 3:1 ratio of CHO:protein [e.g. 45 gm CHO (180 kcal): 15 gm protein (60 kcal)] 4. CHO Loading: Maximizing performance necessitates maximum muscle and liver glycogen stores prior the event. CHO loading is only beneficial for events lasting longer than one hour. Several different protocols exist nowadays, even a one-day protocol. One currently accepted method is to taper your activity for the 6 days prior to the event with the last day resulting in complete rest. On the remaining 3 days, you progressively increase to a CHO-rich diet, at least 70% of calories from CHO. Protein: structural and functional roles within cells Best Sources (Everyday foods):         Chicken (breast-no skin) Eggs (whites=protein) USDA Select beef (the leanest) Turkey (white meat is the leanest) White fish (cod, perch, snapper) Crab, scallops, shrimp, lobster Salmon, mackerel, tuna Soybeans (edamame, tofu, veggie burgers, tempeh) Created by WellCorp, a Nationwide Better Health company, 2007 4 Nutrition for Distance Runners           Legumes (beans—black, garbanzo, kidney, pinto and lentils) Seeds, nuts, and nut butters Soy, rice, skim, or 1% milk Low-fat yogurt Reduced-fat cheese Whey or soy protein powder Requirements: 12-15% of caloric intake Basis for extra protein for endurance athletes is for its small contribution as an energy source. The total amount of amino acids used for fuel during exercise amounts to only 1-6% of the total energy cost of the exercise. Basis for extra protein for strength training athletes is for muscle synthesis and support of additional lean mass. Protein ceiling = 2 g/kg/day With adequate energy and carbohydrate intake; low to moderate intensity exercise has little impact on dietary protein requirements and 1.0g/kg/day is sufficient. For top sport athletes the requirement may be as high at 1.6gm/kg/day. Fat: secondary source of energy Best Sources (Everyday foods):          Canola, olive, walnut, and flaxseed, oil Seeds, nuts, and nut butters Milled flaxseed Olives Avocados Wheat germ Safflower, sunflower, vegetable (soybean) oil Non-hydrogenated margarine spread Fatty fish (salmon, mackerel, tuna) Requirements: 20-28% of daily caloric intake   <10% of calories from saturated fat avoid all trans fat Created by WellCorp, a Nationwide Better Health company, 2007 5 Nutrition for Distance Runners Micronutrients: A nutrient required by the body in small quantities. Calcium: Female Athlete Triad Syndrome 1. Insufficient calorie intake a. Disordered eating b. Overtraining 2. Amenorrhea 3. Osteoporosis Iron: Anemia is a condition that develops when the blood lacks adequate healthy red blood cells, which carry oxygen to tissues. Antioxidants (Vitamin C, E, and Selenium): Immune Function Supplements and Ergogenic Aids: Dietary Supplement and Health Act of 1994: Clarified dietary supplements as neither food nor drugs, therefore they do not require testing or approval by the FDA. No quality control! Supplements that have been tested contain contaminants, lacked claimed ingredients, included unlisted ingredients; contained more or less than stated amount, do not dissolve properly, etc. Hydration: Cascade of events leading to dehydration: 1% -- core body temperature increases 2% -- water plasma volume decreases and muscle water loss occurs 3% -- decreased blood flow to skin 4% -- decreased blood flow to muscles 5% -- decreased sweat rate leads to heat stroke, exhaustion, spasms, and cramping Electrolyte Replacement: Runners should begin the trial and error phase with 400-800 mL (14 – 28 oz) per hour. Hyponatremia: Occurs when runners drink excessively large volumes of water (no electrolyte replacement) for prolonged activity, fluid replacement is far in excess of fluid loss. Created by WellCorp, a Nationwide Better Health company, 2007 6 Nutrition for Distance Runners Debunking Sports Nutrition Myths: MYTH: Don’t eat after 6pm FACT: It might be uncomfortable to go to bed on a full stomach, but if you’re exercising enough and eating well you can eat as your schedule allows MYTH: Carbs always turn into fat FACT: In a balanced diet, carbohydrates fuel your muscles. Athletes especially need carbs to function properly. Remember, any foods eaten that exceed your energy needs will turn to fat. MYTH: Sports drinks should be diluted FACT: Diluting a sports drink diminishes its ability to replace electrolytes you’re losing in sweat. It may change the taste, too – and not for the better! MYTH: High protein/low carb diets are the best way to lose fat and build muscle FACT: Low carb/high protein diets often do not include enough carbohydrate to fuel muscles for the training it take to build muscle mass MYTH: Supplements from the internet are dangerous, supplements from stores are OK FACT: Supplements are not regulated like food, no matter where they’re purchased, their safety should be questioned Adopted from the Gatorade Sports Science Institute and American Dietetics Association Created by WellCorp, a Nationwide Better Health company, 2007 7 Nutrition for Distance Runners Additional Resources: American Heart Association—Healthy Lifestyle, Diet & Nutrition www.americanheart.org Australian Institute of Sport—mission is to educate Olympic athletes and coaches www.ais.org.au Gatorade Sports Science Institute—hydration and sports nutrition www.gssiweb.com Free online nutrition analysis websites: www.fitday.com www.calorie-count.com Sports, Cardiovascular, and Wellness Nutritionists—sponsored by the American Dietetics Association, offers a referral network by state www.SCNAdpg.com Nancy Clark, MS, RD, CSSD—author of ―Food Guide for Marathoners: Tips for Everyday Champions” (2nd edition) www.nancyclarkrd.com Supplements—Monitors the quality of vitamin, mineral, and herbal supplements, nutrition bars, and protein powders www.ConsumerLab.com United States Pharmacopeia (USP) --The official public standards-setting authority for all prescription and over-thecounter medicines, dietary supplements, and other healthcare products manufactured and sold in the United States. www.usp.org Created by WellCorp, a Nationwide Better Health company, 2007 8