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My clients’ standard complaint Nutrition — “Nutrition is my missing link. I’ve got my Your Missing Link? training down, but my eating needs help…” Nancy Clark MS RD CSSD FACSM Sports Nutrition Services, Boston MA www.nancyclarkrd.com Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD Focus of this presentation MISSING LINK #1: Respect for the power of food on performance (and health) • Exercise and weight management • Calories, carbs, protein, fat • Hydration “You know, Nancy, too many • Fueling before, during, and after exercise athletes show up for training but • Caffeine, alcohol don’t show up for meals. They might • Building a balanced sports diet, vitamin supplements as well not show up for training.” BC Hockey Coach Next session on Engineered Sports Foods will cover: Protein supplements, energy drinks, sports foods and drinks, sodium Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD Even lean, fit athletes get heart disease…. MISSING LINK #2: Breakfast! • Brian Maxwell, founder of PowerBar and world class The best energy booster: BREAKFAST marathoner, died at age 51 of a heart attack • Improves quality of overall diet • Andy Palmer, two-time Olympic marathon-trials qualifier • Prevents the need for sugar fixes died at age 48 of a heart attack • Enhances performance • Ed Sheehan, two-time Olympic marathon-trials qualifier died at age 47 of a heart attack Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD 1 Breakfast: The most important meal of the day Breakfast: Better than a quick-fix PC I don’t have time for breakfast. And any ways, I’m not hungry STUDY: Athletes with low glycogen stores biked hard in the morning... for 45 minutes, then sprinted for 15 minutes C I might eat breakfast at 10 a.m. if food were available... Trial Improvements during final sprint P When I do make time to eat in the morning, I have better #1. Baseline: No fuel, only water --- workouts that afternoon—and I don’t get as many headaches… ---Snack five minutes pre-exercise--- A I generally eat breakfast. I just have to plan time... #2. Sugar (180 cals glucose) + water +10 % M I always eat breakfast!!! It boosts my energy, curbs #3. Candy bar (270 cals) + water +10 % evening overeating, and helps me control my weight. #4. Breakfast 4 hrs before + Candy bar + water +20 % (800 cals) Neufer, Costill J Appl Physiol 62(3): 983, 1987 Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD MISSING LINK #3: Knowledge of calorie budget Estimating calorie needs Example: 140 pound female athlete The body needs fuel for– 140 lbs x 10 cal/lb = 1,400 Calories RMR • Resting metabolic rate (Wt x 10 cals/lb) 50% RMR = 700 Daily activity • Daily activities (±50% RMR) 1 hour cardio = 500 Purposeful exercise • Purposeful exercise (400-800 cals/hr) Total calories = 2,600 To maintain weight Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD MISSING LINK #4: How to lose weight appropriately How to eat and be lean–– • Subtract about 10 - 20% from total calorie needs • FUEL ADEQUATELY during the day • Divide calories evenly throughout the day – Have energy to exercise – Prevent ravenous hunger and food binges Example: If an athlete maintains weight on 2,600 calories– 2,600 - 20% (~500 calories) = 2,100 calories/day • EAT REASONABLY at night Breakfast 7-8:00 AM 500 calories – Eat appropriately but do not over-eat. Where’s the Lunch 11-12 noon 600 snack…??? – To lose weight: “I’d rather be leaner than eat more...” Second Lunch 3-4:00 PM 400 Dinner 7-8:00 PM 600 Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD 2 Exercise ≠ weight loss What are you doing with the other non-exercise hours in your day? TRUTH: Exercise enhances weight loss if it The sedentary athlete syndrome…. contributes to a calorie deficit. TRUTH: 30 minutes of exercise = 300 calories 3 minutes of “rewards”= 300+ calories Be aware of compensatory changes in daily activity! Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD Marathon training ≠ Weight Loss! Gender differences: Exercise for weight loss Among 64 novice runners (55% women) in a 3-month marathon- training program: • Men: High level of physical activity Range of weight changes: -27.5 lbs to +12 lbs contributes to a lower % body fat. 11% lost weight (n=7) due to change in eating habits • Women: No relationship between 11% gained weight (6 of the 7 were women) physical activity and % body fat 78% stayed about the same weight (n=50) Kennedy, ACSM 2010 Westerterp Int’l J Obesity 1997; 21(3):184 Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD Gender differences: exercise and appetite Exercise + obese women = weight loss 18 Women did 350 cals of low or high intensity exercise Three trials (19 days each) Their food intake was monitored for 3 days 1. Sedentary (baseline): maintained energy balance Conclusion: 2. Light exercise: burned 10% more cals; ate -114 fewer cals --Hard exercise does not suppress hunger the same way for women as for men. 3. Moderate ex: burned 25% more cals; ate -370 fewer cals --Hard exercise increases attractiveness of food for women No compensation in energy intake Woo, Pi_Sunyer Am J Clin Nutr 1982; 36:470 Pomerleau, Am J Clin Nutr 2004; 80:1230-6 Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD 3 The E in Exercise is for Enjoyment MISSING LINK #5: Adequate carbohydrates Common belief: “Carbs are fattening” Exercise = to train, improve athletic performance = to feel good, relieve stress, A survey of 425 female collegiate athletes across the US reports— improve health, build muscles • The athletes wanted to lose 5 pounds, on average • 43% felt terrified of becoming overweight Exercise ≠ punishment for having body fat ≠ motivated by the desire to burn calories Beals, Manore Int’l J Sports Nutr, 2002 Nancy Clark, MS RD CSSD Nancy Clark, MS RD CSSD Carbohydrates = muscle glycogen 24 What kinds of carbs should I eat? Carbohydrate Diet 20 Carb 16 GLYCOGEN CONTENT 12 (GM/KG MUSCLE) 8 Protein & Fat Diet Pro + Fat 4 0 Rest/ hard exercise 5 15 25 35 45 hours 5 days RECOVERY TIME Nancy Clark, MS RD CSSD Bergstrom, 1967 Nancy Clark, MS RD CSSD Quick & slow carbs MISSING LINK #6: Wrong amount of dietary fat 24 In theory: • Pre-endurance: Slowly digest carbs (Low GI) Carbohydrate Diet 20 Carb • Post-exercise: Quickly digested carbs (High GI) 16 In reality: • The glycemic index of a food varies GLYCOGEN —depends on where grown, how processed, etc. CONTENT 12 (GM/KG MUSCLE) • Each person has unique glycemic response 8 Protein & Fat Diet Pro + Fat —can vary 43% on any given day (Vega-Lopez, 2007) 4 • Athletes should choose well-tolerated carbs 0 Rest/ hard exercise 5 15 25 35 45 hours 5 days Donaldson “Glycemic Index and Endurance Performance” RECOVERY TIME Nancy Clark, MS RD CSSD Int’l J Sports Nutr 20(2)154-165, 2010 Nancy Clark, MS RD CSSD Bergstrom, 1967 4
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