sports nutrition by lyle knudson, ed.d., sports science kristin knudson, b.s., nutrition & food...

SPORTS NUTRITIONby

Lyle Knudson, Ed.D., Sports ScienceKristin Knudson, B.S., Nutrition & Food Science

You are what you eat!!

BENEFITS OF GOOD NUTRITION

Improved Performance Increased Energy in Training Improved Adaptation to Training Improved RecoveryBetter Able to Cope with StressBetter Resistance to Injury/IllnessBetter Recovery from Injury/Illness

Different Sport. Different Fuel.

Different Sport. Different Fuel.

Different Event. Different fuel.

Different Event. Different Fuel.

Gail Devers

100/100H

Stacy Dragila

pole vault

Deena Drossin

10k/marathon

Dawn Ellerbe

hammer

BASIC ELEMENTS OF NUTRITION

Carbohydrates

Fats

Proteins

Vitamins

Minerals

Water

CARBOHYDRATES

LIVER(glycogen)

GLUCOSE

GLYCOGEN(storage form of glucose)

ENERGY (ATP) for muscle contraction

CO2, water, lactic acid

Blood glucose

Energy source for muscles during

exercise

Glycogen stored in liver and muscle

MUST BE replenished after exercise

•Recovery – between exercise bouts

•Adaptation – store more glycogen

USE THEM TO YOUR ADVANTAGE!!

CARBOHYDRATES

CARBOHYDRATES

In practice, competition, or other daily activities:

HITTING A WALLHITTING A WALL==

LOW GLYCOGEN STORESLOW GLYCOGEN STORES

What can you do to avoid this???

CARBOHYDRATES: MEAL TIMINGPre-competition/ practice:

2-4 hours before

Meal high in complex carbohydrates

Low in sugars

Low in fat

Low-Moderate in protein

Snacks during competition/ practice:

Watered-down sports drink

Fruit, veggies, whole-grain cereals/breads

Stay away from fatty, heavy foods & simple sugars

CARBOHYDRATES: MEAL TIMING FOR RECOVERY

Post competition/ practice:

Replenish glycogen (and protein) stores as soon as possible!

• If possible, eat full meal (within ½ hour, not more than 2 hours)

- high in protein & complex carbohydrates, low in simple sugars and starches

• Otherwise, bring food to eat immediately after practice/ competition :

- whole-grain sandwich with meat/cheese/peanut butter, fruit, veggies; energy bar, recovery drink

Different Forms of Carbohydrates

Best Source• Complex carbohydrates from

vegetables, fruits, whole grains- THE MORE COLORFUL THE BETTER- MUST SAY “WHOLE GRAIN” 1st on

INGREDIENT LIST (cereals, bread)

Minimize Source• Simple sugars – soda, candy, desserts• Starches - potatoes• Refined grains- “enriched flour”, cereals,

white bread, pasta

FATS

DIETARY FAT

1. ENERGY- fuel for muscles at rest

2. Assimilation of protein, synthesis of hormones

3. Fat stores

*necessary nutrient

DIFFERENT FORMS OF FATS

Best Source:• Unsaturated and Polyunsaturated

- Fish, nuts, part-skim cheese, avocados, vegetable fats, canola or olive oil

Minimize Source:• Saturated

- Fast food, baked goods, fried foods, high fat meats, whole milk

PROTEIN

DIETARY PROTEIN

PRIMARY PURPOSE:- used to build bodily structures- enzymes

SECONDARY PURPOSE:

- energy

PROTEIN ATHLETE NEEDS 2X AMOUNT OF

AVERAGE PERSON = .5 – 1 gram per pound of body weight per day

KEYS TO UTILIZING PROTEIN FOR MAXIMUM RESULTS:

1. Quality Protein

2. Meal Timing

QUALITY PROTEIN - #1Best Source - animal products

• Fish, lean meats, lean milk, yogurt, eggs, cottage cheese, and part-skim cheese

• contain all essential amino acids

Other Sources – vegetable products

• beans, nuts, seeds, and grains• must be eaten in combinations with others; each does not contain

all essential amino acids

QUALITY PROTEIN - #2 PROTEIN SHAKES & BARS:

• Make conscientious and informed decisions• COMPLETE PROTEINS

- Why not WHEY only?- Milk protein isolate **- Stay away if lists of amino acids included

• 24g protein or less each meal/snack (only eat 1/2 bar if it contains more)• Combo protein/CHO shakes - better• TOO MUCH PROTEIN- hard on kidney, loss of calcium, water, electrolytes in urine

#2-PROTEINS - MEAL TIMINGINCLUDE PROTEIN AT ALL MEALS – EAT LOWEST AMOUNT OF PROTEIN BEFORE EXERCISE; Examples:

Breakfast: 2 eggs, granola w/skim milk,

bananas or strawberries, orange juice, low-fat yogurt

Lunch (before practice): whole wheat bread, lite mayo, 2 slices turkey breast, lettuce, tomato, sprouts, apple/orange

Dinner (recovery): chicken breast over whole-grain pasta with stir-fry of veggies in olive oil

VITAMINS MINERALSA,B1…B15,C, D, E,

K• Promote general

health• Aide in energy

production• Necessary for

proper body function

• Injury prevention

CALCIUM, ZINC, IRON, SODIUM, POTASSIUM, PHOSPHOROUS, MAGNESIUM, ETC.

•Component of body structures•Stimulates chemical reactions; ADP ATP•Neuromuscular stimulation

DIFFERENT SOURCES OF VITAMINS & MINERALS

Best Source - • Balanced diet• fresh vegetables, leafy vegetables, fruit,

lean meat, fish, milk, cheese• natural vitamins & minerals are utilized

more readily than synthetic

Excess Intake of Specific Vitamins or Minerals -• Not proven beneficial• may be harmful; cause excretion of other

needed vitamins & minerals

CALCIUM / VITAMIN D

Of particular concern to women athletesRunning/jumping/throwing are impact

activities that are protective of bone density, so…• WHY DO SOME YOUNG ATHLETES HAVE

LOW BONE DENSITY??- Poor diet- Amenorrhea- see a knowledgeable physician

CALCIUM / VITAMIN DWant to MAXIMIZE bone density

• You are at the perfect age to concentrate on this!

• Less risk of stress fracturesGood sources of Calcium: skim milk,

yogurt, dairy, green leafy veggies, sardines

Vitamin D necessary for absorption of Ca• Fortified dairy products

Consider supplementation??

IRON DEFICIENCYAthletes, especially female distance runners,

have high incidence of iron deficiency anemiaWHY?

• Eat meat?• Lose iron in sweat?? • Foot Strike Homolysis

Leads to Anemia = inability of blood to carry adequate oxygen

Symptoms - fatigue, sore tongue, increased infections

WHAT PREVENTATIVE MEASURES?

Prevent Iron Deficiency!Preventative Measures:

• Allow for full recovery between hard training sessions

• Control running volumes on hard surfaces

• Best dietary sources - red meat, liver, dried fruits, beans; with ascorbic acid

• If necessary, iron supplementation• Have doctors perform complete series

of blood tests checking for size and number of red blood cells

WATER

DEHYDRATIONDEHYDRATION CAN CAUSE:

Muscle cramps

Muscle pulls

Fatigue

HITTING A WALL!!HITTING A WALL!!

Loss of endurance

Overheating

WATER TO AVOID DEHYDRATION:

• Drink 10-12 8 oz. glasses daily

• Carry water bottle everywhere

• Drink ½ cup every 15 min. during training

Well hydrated = pale or clear urine

Do NOT drink too much, should not be

uncomfortable

NUTRITIONAL ISSUES

Balanced diets & food volumes;

athletes vs. non-athletes

Body Weight Maintenance

Vegetarianism

Eating Disorders

Nutritional Supplements

BALANCED DIETS & FOOD VOLUMES; ATHLETES VS. NON-ATHLETES

Average Person, distribution of calories for 2000 calorie dietAthlete, distribution of calories for 3000 calorie diet

0

200

400

600

800

1000

1200

1400

1600

1800

Average Person Elite Athlete

CarbohydratesFatProtein

BODY WEIGHT MAINTENANCE

Optimum weight & body fat %:Best determiner is adaptation to

training and performance in competition

Maximize strength-power to body weight ratio

Optimum body fat % for each individual

WEIGHT CONTROLTO INCREASE BODY WEIGHT:

Drink fruit juices during dayCarry snacks

• Unsalted peanuts, cashews• Chips w/ guacamole• Wheat thins with cheese• Soy nuts

Increase lean mass by strength & power training

WEIGHT CONTROLTO DECREASE BODY WEIGHT:Eat smaller portions during mealsEat snacks more frequently, rather than

large mealsSwitch to low-fat & low-starch foodsEat complex carbohydrates… Fiber helps

fill you up!Eat consistently, at same times each dayNO FAD DIETS!Do not lose more than 2 lbs/week

VEGETARIANISMNOT RECOMMENDED!! BUT IF YOU’RE GOING TO:

• Must consume a wide variety of vegetables, fruits, seeds, milk, and eggs

• A vegan (no animal products) diet is very difficult to maintain. Deficiencies may result.

• Consider protein & mineral (especially iron and calcium) supplementation

EATING DISORDERS

CATEGORIES OF EATING DISORDERS:Malnutrition - improper balance of

nutrientsOver-weight - excessive food intakeUnder-weight - inadequate food intakeAnorexia - excessive self-control

expressed with dietBulimia - lack of food-intake control,

then purging

EATING DISORDERSCAUSES: Lack of nutrition knowledge’s, understandings,

and/or applicability's Eating what’s most readily available Psycho-Social -

• Excessive self-control - perception of unrealistic expectations from others, idealized body image

• Lack of self-control• Cumulative psycho-social stress

Physical - • Cumulative physiological stresses• Lack of recovery-adaptation between

training/competition sessions

EATING DISORDERS

RESULTS: Disappointing performances

Lack of positive adaptation from training (lack of

improvement)

Lack of recovery from training/competition

(cumulative fatigue)

Lack of ability to cope with stress

Injury, & lack of ability to recover from injury

Illness, & lack of ability to recover from illness

EATING DISORDERS

SOLUTIONS: Know yourself; regarding your psycho-social

& physical status

• As affecting your eating habits

• As affected by your eating habits

Learn and apply proper nutrition practices

Work at it

Coaches - If you make an issue of it, it will

become an issue!! Deal with carefully on

individual basis.

NUTRITIONAL SUPPLEMENTS

ERGOGENIC AIDS:Few have been PROVEN effectiveNOT FDA regulatedSome effective for specific purposesNegative side effectsLegal vs. Illegal issuesSee NCAA &/or USOC website to check

for banned substancesIf considering use, get educated

SUMMARY

If you want to be an Olympian, eat like it.

SUMMARY, FOR COACHES AND PARENTS

It’s OK for you to exercise, and eat right, too!!