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Youth Exercise & Sport – Relevance of “Sports” Nutrition?. Jennifer Sacheck, PhD Tufts University Friedman School of Nutrition Science & Policy John Hancock Center on Physical Activity, Nutrition, and Obesity Prevention. The National Crisis. ~32% Kids 2-19 yrs. ~69% Adults.
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Youth Exercise & Sport – Relevance of “Sports” Nutrition? Jennifer Sacheck, PhD Tufts University Friedman School of Nutrition Science & Policy John Hancock Center on Physical Activity, Nutrition, and Obesity Prevention
The National Crisis ~32% Kids 2-19 yrs ~69% Adults APOP, IOM, 2012
Energy In vs. Energy Out Dietary IntakePhysical Activity
Development of Childhood Obesity Less Sleep Plethora of Low Cost/Energy Dense Foods Multi Media Saturation Increased Portion Sizes Physical Education and Recess Cuts Energy OUT Energy IN Food Advertising/ Marketing Aimed at Children Declines in Physical Activity Sugar Sweetened Beverage Consumption Changing Built Environment Frequent Eating Away from Home
We Eat Too Much…. SPAGHETTI & MEATBALLS 20 Years Ago Today 500 calories 1 cup pasta w/ sauce 3 small meatballs 1,025 calories 2 cups of pasta w/ sauce 3 large meatballs Caloric Difference: 525 calories
Estimated Calorie Requirements by Age and Activity Level (Institute of Medicine Dietary Reference Intakes, 2002)
Contribution of Solid Fats and Added Sugars to Energy Intake Among Children and Adolescents in the United States Reedy J, et al. J Am Diet Assoc; 2010; Volume 110 (Oct).
Food Sources and Mean Intake of Empty Calories for Male Children and Adolescents, Relative to Discretionary Calorie Allowance Discretionary calorie allowance Soda Soda Soda Whole milk 290 195 171 165 Males (by age) Data Source: NHANES 2003-04 Reedy J, et al. J Am Diet Assoc; 2010; Volume 110 (Oct).
WHITE, CANE, BEET, FRUIT, TABLE, BROWN, & HFCS….& HONEY, MAPLE SYRUP, & AGAVE And what about sugar?.....
Sources of Dietary Added Sugars:Americans Ages 2+, NHANES 2005-2006
Total Television Food Advertising Exposure, by Age Teens see 14 ads/day Rudd Report TRENDS IN TELEVISION FOOD ADVERTISING. Data Used from Nielsen Report (2008)
Lack of Physical Activity Can Johnny Come Out and Eat?
Physical Activity Guidelines for Children Children and adolescents should do 60 minutes or more of physical activity daily. Aerobic: Most of the 60 or more minutes a day should be either moderate- or vigorous-intensity aerobic physical activity, and should include vigorous-intensity physical activity at least 3 days a week. Muscle-strengthening: As part of their 60 or more minutes of daily physical activity, children and adolescents should include muscle-strengthening physical activity on at least 3 days of the week. Bone-strengthening: As part of their 60 or more minutes of daily physical activity, children and adolescents should include bone-strengthening physical activity on at least 3 days of the week.
Youth Meeting Physical Activity Guidelines Troiano R, et al. Medicine & Science in Sports & Exercise, 2008. Massachusetts Youth Risk Behavior Survey, 2011
Youth Cardiorespiratory Fitness 12-19 yrs (NHANES 1999-2002) • ~65% of males and females met the standard Females Males Pate et al 2006 19
Physical Education 150 min/week for elementary and 225 min/week of PE for middle and high school students APOP, IOM, 2012
Media Blitz APOP, IOM, 2012
Contribution of Organized Sports to • Physical Activity Recommendations • Physical Activity During Youth Sports Practices Leek, D. et al. Arch PediatrAdolesc Med 2010;0:archpediatrics.2010.252v1-6.
Moderate to Vigorous Physical Activity (MVPA) during Practice and Participants Meeting PA Guidelines by Sex Leek, D. et al. Arch PediatrAdolesc Med 2010;0:archpediatrics.2010.252v1-6.
Contribution of Organized Sports to • Physical Activity Recommendations: • Physical Activity During Youth Indoor Soccer Games • Sacheck, et al. Pediatric Exercise Science, 2010
Out of School Time – Organized SportsTime spent at various intensities of physical activity during a 50-min soccer match Values are means (SD). Moderate-to-vigorous activity (MVPA). * P < 0.05, ** P < 0.01, vs. females Sacheck et al, PedExerSci, 2010
% Time spent in different intensities of physical activity during a 50-min soccer match by BMI category N NNormal Weight Overweight/Obese N NNormal Weight Overweight/Obese Values are means SE. Different than normal weight individuals **P<0.01
Estimated kcals for BMR, AEE, and TEE during a 50-min soccer match by BMI category N NNormal Weight Overweight/Obese N NNormal Weight Overweight/Obese BMR = basal metabolic rate; AEE = activity energy expenditure; TEE = total energy expenditure (BMR + AEE). Values are means SE. Different than normal weight individuals *P<0.05, **P<0.01
Poor Health Outcomes WHO estimates that 1.9 million deaths worldwide are attributable to physical inactivity APOP, IOM, 2012
The Somerville FIT Study **P<0.001
Combined Impact of Fitness & Fatness on Metabolic Risk Factors in Children Black Bars = unfit
Mean Number of Fitness Tests Passed by BMI Percentile Kim et al Obes Res 2005 End run, ab strength, flexibility, upper body strength and agility
What is happening? • Obese children may: • have a more difficult time moving their body against gravity • Be more likely to have physical complications/pain during PA • perform less PA so that they also have less opportunity to practice and develop proficiency • have fewer opportunities for and have less enjoyment in PA
Adult Fitness, BMI and CVD Mortality in Men • Fitness trumps “fatness” (Aerobics Center Longitudinal Study) Lee et al Circulation 2011
Likelihood of Passing Academic Tests For Each Fitness Test Passed by Massachusetts Students in Grades 4 to 8 Odds of passing increased by 24% per test passed Odds of passing increased by 38% per test passed Chomitz V, et al. Journal of School Health, 2009.
Kids: Sports Nutrition Issues • Consuming adequate calories • Eating consistent meals • Getting a good balance of foods/nutrients (carbohydrate, protein, & fat) • Refueling after exercise • Drinking enough fluids • Most appropriate fluids • Inappropriate use of sports drinks, bars and supplements
Estimated Calorie Requirements by Age and Activity Level (Institute of Medicine Dietary Reference Intakes, 2002)
Macronutrient Needs • Protein: 10-30% calories • Carbohydrate: 45 to 65% calories • Fat: 25-35% calories • 5 to 10% as linoleic acid • 0.6 to 1.2% as linolenic acid
Protein Needs: 0.8-1.2 g/kg/day • Here are examples of amounts of protein in food: • 1 cup of milk has 8 grams of protein • A 3-ounce piece of meat has about 21 grams of protein • 1 cup of dry beans has about 16 grams of protein • An 8-ounce container of yogurt has about 11 grams of protein
WHAT TO EAT? • 2/3 carbohydrates: • 1/3 bread, bagels, cereal, rice, pasta, crackers, pretzels • 1/3 vegetables, beverages • 1/3 protein OR LESS: • Meat, poultry, fish, dairy foods, nuts, seeds, soy foods, dried beans, eggs
Nutrient Needs: Critical Minerals Calcium • Most important for obtaining peak bone mass at this age Iron • Increased need related to rapid rate of linear growth, increase in blood volume, and in females, onset of menarche Zinc • Required for sexual maturation, important co-factor in enzymes
Thermal Stress and Children • Children rely more on convection and radiation, which are enhanced through greater peripheral vasodilation • Evaporative heat loss is lower because of reduced sweat rates • Children have greater ratios of surface area to mass • Acclimatization to heat is slower in boys than in adult men (no data available for girls)
Sport Drinks • Uniquely designed to meet both energy and fluid needs of athletes • Composition influences gastric emptying • Carbohydrate solutions empty more slowly • Most sports drinks contain: • 6-8% CHO in the form of glucose and glucose polymers • 20-60 mmol/L sodium • Adding glucose stimulates sodium and water absorption • Sodium increases thirst
Who Really Needs Sports Drinks? • American Academy of Pediatrics: • “If children are participating in prolonged vigorous physical activity in hot, humid conditions for more than one hour, small amounts of sports drinks may be appropriate” • 2010 National Youth PA & Nutrition Study • 16% drank at least one serving/day • 9% drank at least two servings/day • Participation in varsity sports: 33% (girls) 37% (boys) Johnston LD, et al. Am J Prev Med 2007; Volume 33 (Oct).
Hydration BEFORE – Water! • 1-2 hours before: 2-1/2 cups (20 oz.) • 15-30 min before: 1-1/2 cups (12 oz.) DURING – Water! 8 oz every 15-20 min • diluted fruit juice, sports drinks (6-8%) IF exercise is >60 min AFTER – Water! Drink 2 cups for each pound lost • Weigh yourself before and after exercise • Don’t trust thirst • Avoid caffeine
Potential side-effects Increased urination Gastrointestinal distress Tremors Decreased sleep Nervousness/Anxiety symptoms Irregular heart rate/rhythm Caffeine Benefits Increases: • Mental alertness • Concentration • Catecholamine release • Use of fats by muscles • Decreases fatigue & lowers perception of effort • Improves endurance performance • May improve sprint/strength performance