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Introduction to Nutrition in the Collegiate Athlete. Enrique Saguil, MD Integrative Sports and Wellness. TMI. ???????. All have 35gm carbs, 35gm sugar, 0g protein. From the CDC website:. South Beach and Atkins Diet: Both are modified versions of a low carbohydrate diet
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Introduction to Nutrition in the Collegiate Athlete Enrique Saguil, MD Integrative Sports and Wellness
South Beach and Atkins Diet: • Both are modified versions of a low carbohydrate diet • Much of weight loss due to low carb intake and can result in lower stored glycogen • Glycogen is the “electricity” stored in the body’s back up “battery”
During sprinting, the energy needed by the working muscles for contraction must be provided at a very high rate. This is achieved mainly through the anaerobic degradation of two compounds stored in the muscles, namely phosphocreatine (PCr) and glycogen leading to lactic acid formation. Phosphocreatine breaks down rapidly at the onset of maximal exercise but can provide enough energy for only 5-10 seconds. Muscle glycogen is also utilized very rapidly at the onset of maximal exercise although there is a progressive decline in energy provision from this fuel. Consequently, as maximal exercise continues for several seconds performance begins to decline even in the presence of adequate glycogen stores, probably due to the depletion of PCr and the accumulation of products of anaerobic metabolism such as lactic acid.
For these reasons, a high carbohydrate diet consumed at appropriate times before and after exercise (7-10g/kg body weight daily) has to become accepted practice among players. In soccer, for example, players who start the match with low glycogen concentration in the leg muscles, cover a shorter distance and sprint significantly less, particularly in the second half, compared with players who have initially normal glycogen levels prior to the match. In addition, consumption of 6% carbohydrate solution during prolonged high-intensity intermittent running spares muscle glycogen utilization. Thus, it is clearly advantageous for an athlete who participates in multiple sprint sports to increase carbohydrate consumption before, during and after exercise to cope with heavy training and competition.
Output = Input • Muscle energy = glycogen storage • Glucose sustains short energy burst • Glycogen will cover more endurance activity • Expenditure depends on storage/supply
Poor storage will lead to poor long term performance Poor endurance will translate to late game loss Equally matched teams can be separated by nutrition status
Candace Booth, ND • Breakfast – protein shake • Snack – protein bar • Lunch – veggie/protein (avoid starches) • Snack – fruit • Dinner – veggie/starch (dont mix)
Dietitians of Canada, American Dietetic Association and American College of Sports Medicine • All agree that physical activity, athletic performance and recovery from exercise are enhanced by optimal nutrition
glycogen depleation = hitting the wall/bonking
Fat, proteins and carbs can be burned as fuels but fats and proteins can’t be oxidized as fast as carbs for high intensity exercise • Adequate carbs must be consumed daily to restore glycogen • Low glycogen decreases serum glucose, increases risk for hypoglycemia will decrease endurance
Protein recommendations are: 1.6 – 1.7 gm protein per kg of body weight ie….a 200 lb athlete needs 145-154gm protein/day
Fish,3oz, 21 gmschicken, 3oz, 21gmsturkey, 3oz, 21 gmsmeat, 3oz, 21gmsmilk, 8oz, 8gmstofu, 3oz, 15gmscheese,3oz, 21gmspeanut butter, 2 tbsp, 8gmseggs, 2 large, 13gms
Carb recommendations vary:3-4 gm of carbs per pound of body weight per dayie….. a 200 lb athlete needs 600-800 gm of carbohydrates/day( 25% post exercise )
Daily caloric intake should be divided into fats – carbs - proteins • Fat has 9 calories per gram • Carbs and proteins have 4 calories per gm • Most dietary programs list carb intake as the highest at 30-50% • Proteins and fats both vary between 20-30%
When to eat • Stomach takes 1-4 hours to digest • Closer to the event, take things easy to digest- liquids generally faster! • Pre-event meals should be high in carbohydrates
3-4 hours before competition • Fresh fruits or veggies • Bread and bagels • Pasta with tomato sauce • Baked potatoes • Energy bar • Cereal • Low-fat yogurt • Toast/bread with limited pb, lean meat, cz • 30oz sports drink
2-3 hours before competion • Fresh fruit • Fruit or veggie juices • Bread, bagels • Low-fat yogurt • Sports drink
1 hour or less before competition • Fruit or vegetable juice such as orange, tomato, or V-8 • Fresh fruit apples, watermelon, grapes • Energy gels • Up to 1 and ½ cups sports drink
3 days before event (carb loading) • Reduce exercise to avoid depleating current glycogen stores • Rest completely 1-2 days before event • Increase the amount of carbs to 60-70% of the calories you eat (fats=15-20, pro=10-15) • Watch for wt gain (in form of water), bloating and high sugars.
During event • Continue with carbs during the event • 5-8 oz of a carb containing drink every 15 minutes • More if temp is hot
Avoid fat: • Fast food • Hot dogs • Nachos • Potato chips • Candy bars
Post game • Studies show if not taken within 2 hours, 50% less glycogen stored in muscle (carbs stimulate insulin production which aid in production of glycogen production) • Combine protein and carb for greater absorption, if taken w/in 2 hours doubles the insulin response • 4 gms carbs to every 1gm protein but watch rehydration
Products on the market already 4:1 • Endurox r4 • Accelerade • Powerbar • Energy gels with adding 1 tbsp of protein powder for every 25 gms carb
Early postexercise muscle glycogen recovery is enhanced with a carbohydrate-protein supplement.Ivy JL, Goforth HW Jr, Damon BM, McCauley TR, Parsons EC, Price TB.Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, University of Texas at Austin, Austin, Texas 78712, USA.In the present study, we tested the hypothesis that a carbohydrate-protein (CHO-Pro) supplement would be more effective in the replenishment of muscle glycogen after exercise compared with a carbohydrate supplement of equal carbohydrate content (LCHO) or caloric equivalency (HCHO). After 2.5 +/- 0.1 h of intense cycling to deplete the muscle glycogen stores, subjects (n = 7) received, using a rank-ordered design, a CHO-Pro (80 g CHO, 28 g Pro, 6 g fat), LCHO (80 g CHO, 6 g fat), or HCHO (108 g CHO, 6 g fat) supplement immediately after exercise (10 min) and 2 h postexercise. Before exercise and during 4 h of recovery, muscle glycogen of the vastus lateralis was determined periodically by nuclear magnetic resonance spectroscopy. Exercise significantly reduced the muscle glycogen stores (final concentrations: 40.9 +/- 5.9 mmol/l CHO-Pro, 41.9 +/- 5.7 mmol/l HCHO, 40.7 +/- 5.0 mmol/l LCHO). After 240 min of recovery, muscle glycogen was significantly greater for the CHO-Pro treatment (88.8 +/- 4.4 mmol/l) when compared with the LCHO (70.0 +/- 4.0 mmol/l; P = 0.004) and HCHO (75.5 +/- 2.8 mmol/l; P = 0.013) treatments. Glycogen storage did not differ significantly between the LCHO and HCHO treatments. There were no significant differences in the plasma insulin responses among treatments, although plasma glucose was significantly lower during the CHO-Pro treatment. These results suggest that a CHO-Pro supplement is more effective for the rapid replenishment of muscle glycogen after exercise than a CHO supplement of equal CHO or caloric content.
Effects of recovery beverages on glycogen restoration and endurance exercise performance.Williams MB, Raven PB, Fogt DL, Ivy JL.Cardiovascular Research Institute, University of North Texas, Health Science Center at Fort Worth, Texas 76107, USA. johnivy@mail.utexas.eduThe restorative capacities of a high carbohydrate-protein (CHO-PRO) beverage containing electrolytes and a traditional 6% carbohydrate-electrolyte sports beverage (SB) were assessed after glycogen-depleting exercise. Postexercise ingestion of the CHO-PRO beverage, in comparison with the SB, resulted in a 55% greater time to exhaustion during a subsequent exercise bout at 85% maximum oxygen consumption (VO(2)max). The greater recovery after the intake of the CHO-PRO beverage could be because of a greater rate of muscle glycogen storage. Therefore, a second study was designed to investigate the effects of after exercise CHO-PRO and SB supplements on muscle glycogen restoration. Eight endurance-trained cyclists (VO(2)max = 62.1 +/- 2.2 ml.kg(-1) body wt.min(-1)) performed 2 trials consisting of a 2-hour glycogen-depletion ride at 65-75% VO(2)max. Carbohydrate-protein (355 ml; approximately 0.8 g carbohydrate (CHO).kg(-1) body wt and approximately 0.2 g protein.kg(-1) body wt) or SB (355 ml; approximately 0.3 g CHO.kg(-1) body wt) was provided immediately and 2 hours after exercise. Trials were randomized and separated by 7-15 days. Ingestion of the CHO-PRO beverage resulted in a 17% greater plasma glucose response, a 92% greater insulin response, and a 128% greater storage of muscle glycogen (159 +/- 18 and 69 +/- 32 micromol.g(-1) dry weight for CHO-PRO and SB, respectively) compared with the SB (p < 0.05). These findings indicate that the rate of recovery is coupled with the rate of muscle glycogen replenishment and suggest that recovery supplements should be consumed to optimize muscle glycogen synthesis as well as fluid replacement.