Objectives Increase awareness that nutrition can affect an athlete’s performance Discuss current nutritional recommendations for athletes Review the 1994.

Nutrition and Nutritional

Supplements in Sports

ObjectivesIncrease awareness that nutrition can affect an

athlete’s performanceDiscuss current nutritional recommendations for

athletesReview the 1994 Dietary Supplement Health and

Education ActDefinition of a supplement Impact of this legislation

Discuss specific nutritional supplements commonly used by athletesDo they work?Are they safe?

Performance Influencing Factors

Genetics

Training and Conditioning

Nutrition

Basics of Nutrition6 Classes of NutrientsMacronutrients

Carbohydrates (CHO)FatsProteins (PRO)

MicronutrientsVitaminsMineralsWater

Determinants of the Athlete’s Energy Requirements

During intense exerciseCarbohydrate stored in muscles and liver

(glycogen) is predominant fuel sourceDuring prolonged exercise

Fat stores are predominant fuel sourceFitness level of the athlete

Well trained endurance athletes burn fat more efficiently, sparing limited glycogen stores

Formula for Rough Estimation of the Body’s Calorie Requirements

Sedentary personWeight (kg) x 25

Moderately active personWeight (kg) x 30

Active person (endurance athlete)Weight (kg) x 40

Underweight personWeight (kg) x 45

kg = lbs / 2.2

CarbohydratesSimple (sugars) and Complex (starches)Major & most efficient fuel source for exercising

muscle

4 kcal/gmAthletes should ingest 6 to10 gm/kg/day

55 to 60 % of total calories should come from carbohydratesComplex carbohydrates (starches) are preferable

During exerciseAthletes should consume 25 to 30 gm of carbohydrate for

every 30 minutes of exerciseAthletes should drink 6 to 8 ounces of water or sports drink

for every 10 to 15 minutes of exercise

CarbohydratesAfter exercise

Athletes should consume 1.0 to 1.5 gm/kg immediately post exercise and again one hour later Decrease in storage efficiency the greater duration

of time To replace muscle glycogen stores To prevent gradual depletion of muscle glycogen

stores over time caused by repetitive daily bouts of heavy exercise

To decrease muscle breakdownChocolate Milk?

Why Complex Carbohydrates?Compared to ingesting simple

carbohydrates (sugar), ingesting complex carbohydrates (starch and fiber):Increases muscle glycogen stores betterImproves performance and delays fatiguePromotes faster stomach emptyingCauses less stomach upset and indigestionLeads to lower blood sugar and insulin levels Provides other beneficial nutrients

Fiber, vitamins and minerals

ProteinAthletes require more protein than non-athletes

15 to 20% of total calories should come from protein4 kcal/gmProtein intake should be tailored to type of training

1.2 to 1.4 gm/kg/day recommended for endurance athletes 1.7 to 1.8 gm/kg/day recommended for strength athletes

Average American diet provides 1.4 gm/kg/dayAdequate calorie intake is just as important as

adequate protein intake for building musclesToo much protein intake can be bad

Excess protein calories are stored as fatExcess protein intake can lead to dehydration and may

contribute to kidney problems

FatMajor source of energy

9 kcal/gm25 to 30% of total calories should come from

fatLess than 10% of total calories should come from

saturated fatsCholesterol intake should be less than 300

mg/dayAverage American diet provides 37% of total

calories from fat

Pre-exercise MealImportance

Less hunger before and during exerciseMaintains optimum glycogen stores

RecommendationsEmphasize complex carbohydrates

(starches) 1 to 4 gm/kg about 1 to 4 hours prior to event Consume less closer to event

Avoid high fat and high protein foods Slower gastric emptying can cause stomach

upsetAvoid high fiber or gas forming foods

Can lead to crampy abdominal pain

Carbohydrate LoadingAthlete should have overall high

carbohydrate dietBody is more efficient at storing CHOIncreases the body’s pre-exercise

glycogen stores by 50 to 100%Benefits endurance athletes who compete

for longer than 90 minutesCan increase endurance up to 20%Can increase performance by 2 to 3%

Carbohydrate Loading:One Example of How

Days prior to eventExercise duration Carbohydrate intake

6 90 minutes 5 gm/kg/day 5 40 minutes 5 gm/kg/day 4 40 minutes 5 gm/kg/day 3 20 minutes 8 gm/kg/day 2 20 minutes 8 gm/kg/day 1 rest 8 gm/kg/day

Body CompositionMeasures

HydrostaticElectrical impedanceSkinfold thickness

Endurance AthletesMen: 8-12%Women: 10-18%

NOT BELOWMen: 3%Women: 12%

Weight ControlBody Composition

Refers to fat and non fat componentsPercentage of body fatLean body weight

Two FactorsNumber of adipose (fat) cellsSize of adipose cells

1 lb. of fat = ~3500 kcal

Weight Loss & GainWeight Loss

Safe weight loss is 1-2 lbs. per weekExercise utilizes fat stores 80-90% with almost

no loss of lean massDieting alone may decrease lean mass 35-40%

Weight GainApproproiately gain 1-2 lbs. per weekAim to increase lean body massAdd 500-1000 kcal a weekMUST include weight training

Nutritional Supplements1994 Dietary Supplement Health and

Education ActDefinition of a supplement

Any product that contains vitamins, minerals, amino acids, herbs, botanicals or a concentrate, metabolite, constituent, extract or combination of any of these ingredients

Removed dietary supplements from FDA regulation on the front end

FDA must prove a supplement is dangerous before its sale can be prohibited

Nutritional Supplements1994 Dietary Supplement Health and

Education ActManufacturers do not have to provide scientific

proof of claimsManufacturers cannot state product is meant

to diagnose, treat, prevent or cure a disease but can make indirect suggestions

Created a multi-billion dollar industry that continues to grow rapidly

Vitamins and MineralsEssential nutrients

Human body needs these to produce energyNo evidence in U.S. studies that taking vitamin

and mineral supplements improves athletic performanceBeing deficient in vitamins or minerals is rare in the

U.S. compared to the rest of the worldA few studies outside U.S. showed an effect

Did population studied have some baseline deficiency treated with these supplements?

Vegetarian athletes are at risk for being deficient in vitamins B12, D, riboflavin, iron, zinc and calciumAthletes who are strict vegetarians should take a

multivitamin to prevent deficiencies and a calcium supplement (1000 mg/day) to help prevent bone loss

Anabolic Steroids and Anabolic Steroid Precursors

Are banned and tested for by the USOC, IOC, NCAA, NFL, NBA and MLB

NHL has no official policy and does not perform testing

You can be disqualified from participating in college sports if you test positive for a substance banned by the NCAAWhether or not you knew it was bannedWhether or not the product was mislabeled

Buyer Beware! IOC funded study by Shanzer (Germany) from 10/00 to

11/01 Analyzed 634 products labeled as non-hormonal nutritional

supplements from 13 countries and 215 different suppliers 94 products (14.8%) were found to be “positive supplements”

(contained anabolic steroid precursors not declared on the label) Anabolic androgenic steroid concentrations ranged from 0.01 to

190 micrograms per gram of supplement 23 products contained steroid precursors of nandrolone and

testosterone 64 products contained steroid precursors of testosterone only 7 products contained steroid precursors of nandrolone only Percentage of positive supplements per country

25.8% of products bought in Netherlands 22.7% of products bought in Austria 18.8% of products bought in UK 18.8% of products bought in US (45 positive out of 240 tested)

ConclusionsNutrition plays an important role in an

endurance athlete’s ability to performProper nutrition in combination with

sound and proven training techniques can help endurance athletes to maximize their genetic abilities

Certain nutritional supplements have not demonstrated any performance benefit in studies

ConclusionsCertain nutritional supplements can have

potentially dangerous side effectsFurther legislation is needed to address the

dangers of some nutritional supplementsProfessionals in the community need to be

resources of good information for athletes, parents and coaches PhysiciansPhysician assistantsNurse practitionersAthletic trainersSchool nursesDieticians