Eating for Competing

Dr Helen O’ConnorDepartment of

Exercise and Sport Science

University of Sydney

NSW Institute of Sport

Overview of the Presentation

• A healthy diet• Pre-event meal• During the event• Recovery • Common

questions

Nutrition Basics Checklist

• Varied and balanced diet → good health• Carbohydrate → energy & recovery• Moderate to low in fat → health• Adequate protein → grow & muscle• Adequate fluid → hydration• Regular meals → energy &

concentration

Carbohydrate the Key to Energy & Recovery

• Stored as glycogen• Important energy source • Limited body stores• Improves endurance,

concentration and recovery

How Much Carbohydrate do I Need?

Activity g carb/kg/day

Couch Potato 4-51 hr light exercise 5-61-2 hours medium-light 6-72 hours medium exercise 7-83-4 hours medium-hard 8-9Crazy people (ultra-endurance) 10

Low GI Foods Produce Higher Satiety

0

50

100

150

200

250

Glucose AUC Satiety AUC Food eaten at 2 hr(g)

Low GI

High GI

P<0.01P<0.01

P<0.05

Holt & Brand-Miller Appetite 1995

Rice cakes of identical appearance, energy content, nutrition composition

0 10 20 30 40 50 60 70 80 90 100

BreakfastCereals

Sanitarium Weet-bix

Porridge

Untoasted Muesli

Toasted Muesli

Kellog's Cornflakes

Kellog's Coco Pops

Kellog's All Bran

Glycaemic Index

Glycaemic IndexBreakfast Cereals

0 10 20 30 40 50 60 70 80 90 100

Breads

Fruit Loaf

Kibble Barley (av)

Mixed Grain (av)

Oat Bran (av)

Rye/Kernel

Wholemeal (av)

White

Glycaemic Index

Glycaemic IndexBreads

0 10 20 30 40 50 60 70 80 90 100

Fruit

Watermelon

Pineapple

Grapes

Cherries

Banana

Apricot (dried)

Apple/Pear (av)

Glycaemic Index

Glycaemic IndexFruit

0 10 20 30 40 50 60 70 80 90 100

Vegetables

Peas (green)

Carrots

Sweetcorn

Pumpkin

Sweet Potato (av)

Fries (av)

New Potato (av)

Baked Potato (av)

Glycaemic Index

Glycaemic IndexVegetables

0 10 20 30 40 50 60 70 80 90 100

Legumes

Soya Beans (av)

Kidney Beans (av)

Chick Peas (av)

Butter Beans (av)

Baked Beans (av)

Glycaemic Index

Glycaemic IndexLegumes

0 10 20 30 40 50 60 70 80 90 100

Pasta

Vermicelli

Spaghetti (av)

Meat Ravioli

Egg Fetucine

Glycaemic Index

Glycaemic IndexPasta

0 10 20 30 40 50 60 70 80 90 100

Rice

Brown

Doongarra/Basmati

Calrose

Long Grain White

Glycaemic Index

Glycaemic IndexRice

0 10 20 30 40 50 60 70 80 90 100

Sugars/Con-fectionery

Sucrose

Glucose

Fructose

Honey

Muesli Bars

Mars Bars

Jellybeans

Chocolate

Glycaemic Index

Glycaemic IndexSugars/Confectionery

Case StudyMark: Cricket UmpireWeight: 85 kg (ideal weight 70 kg)Work: Office jobUmpire: Once a week on SaturdayCarbohydrate needs: 5 g carb/kg/dayDaily needs: 70 x 4 = 280 g carb/day

30 g fat/day 1,500 kcal (6,300 kJ)/day

Easy Carbohydrate Counter

Food Carbohydrate (g)Bread (1 slice) 151 small box breakfast cereal 20Fruit (1 average piece) 20 1 medium potato 151 cup cooked rice 501 cup cooked pasta 351 carton yoghurt (200 g) 25300 ml milk 15

Case Study - MarkFood Consumed

Carbohydrate (g)2 servings of cereal 40Bread 4 slices 60Fruit 3 pieces 60Milk 15Rice/Pasta/Potato 50Mixed vegetables 50

Total 275

Breakfast

2 Cups CerealMilk150 ml Fruit Juice (1 fruit)

Carbohydrate: 70 g

Lunch

2 salad sandwiches (grain bread) with lean meat, cheese, fish or egg

1 piece fresh fruit

Carbohydrate: 75 g

DinnerLean meat, chicken, fishPotato (2) or Rice 1 cup cooked

(basmati or Doongara) or Pasta (1 cup)

Vegetables 3-5 typesFresh fruit

Carbohydrate: 120 g

Smart Snacks• Fresh fruit• Fruit yoghurt• Wholegrain toast (little spread)• Fruit toast (little spread)• 8 vita-weet with light cheese• Low fat milk smoothie• Bowl wholegrain cereal with light milk• Low fat vegetable soup

Low GI carbs with lean protein for maximum satisfaction

Nutrition Essentials

1-2 Treats/ week

Fat the Hidden Opponent

Too much fat can:• Replace carbohydrate• Delay digestion• Increase risk for body fat

gain• Heart and other health

problems in later life

Reducing Fat Intake

Decrease added fats

Reducing Fat Intake

Remove fat from meat and skin from chicken

Reducing Fat Intake

Reducing Fat Intake

Reducing Fat Intake

Protein

• Requirements about 0.75 g/kg/day• Most Australians already eat twice as

much as they need• Lean protein can help you to feel full

Weight Gain Risk Factors

• Desk job• Family history• “Off” or “Holiday” seasons• Eating on the run• Fast food, snacking• Grazing ??• Other...

Why Low CHO Diets?

• Popular at present• Claims for substantial weight loss• Against traditional nutrition

principles• Safety, effectiveness, performance?• Public frustrated with weight loss

Popular Lower CHO diets

Older Diets Newer DietsDr Atkins Diet Sugar BustersStillman’s Diet CHO Addicts The Drinking Man’s Diet Protein PowerThe Scarsdale DietThe Airforce Diet

Ketogenic Diets• Dr Atkins Prototype• Switch from glucose to

fat or starvation metabolism

• Lean mass spared?

RCT Low CHO Diet for Obesity

n=63 (43F; 20M)

LCHOn=33

Atkins Diet

LFn=30

15% P; 30%F; 60% CHO

Attrition3 Mo: n=286 Mo: n=24

12 Mo: n=20

Attrition3 Mo: n=216 Mo: n=18

12 Mo: n=17

Foster et al NEJM 2003

RCT Low CHO Diet for Obesity

-8

-7

-6

-5

-4

-3

-2

-1

0

0 3 6 12

Time (months)

Ch

an

ge

in W

eig

ht

(%)

LCHO

LF

*P=0.002

*P=0.03

P=0.27

Foster et al NEJM 2003Base values carried forward for drop-outs

Fluid Replacement

• Drink regularly• Thirst is a poor indicator of needs• Dehydration of only 1% of body weight

can decrease exercise performance• Start each session well hydrated• Replace fluids during and after each

training session

Drink-Up

• Drink 300-500 ml 30 min prior to umpiring

• Drink around 250-500 ml over session• Use weight before and after exercise to

approximate fluid losses• Each kilogram = 1 L sweat• Replace 1.5 times fluid loss to rehydrate

after the session

Benefits of Sports Drinks

• Superior hydration• Enhanced fluid consumption• Carbohydrate replacement• Electrolyte replacement• Delay fatigue during

exercise

Intestinal Uptake

Blood Gut Lumen

Water

Sports drink

G G

GG

GG

Gs

s

s

s

0 1000 2000 3000 4000

Warm Water (15C)

Cool Water (5C)

Cool FlavouredWater (citrus)

Flavouring & Cooling a Solution will Flavouring & Cooling a Solution will Increase Voluntary Consumption by Increase Voluntary Consumption by

WorkersWorkers

Hubbard RW et al., 1984.

Average fluid consumption over 6 hour period Average fluid consumption over 6 hour period (ml) during moderate work at 40(ml) during moderate work at 4000CC

Energy Drinks

Drink (/100 ml) CHO (g) Na (mg) Caffeine (mg)

Black Stallion 10.8 46 32Lift Plus 11.7 19.8 17.4Lipovitan 10.4 12 16.8Professor Heads 14.1 11.7 32Prof Heads (Brain) 13.2 11.4 32Red Bull 11.2 80 32

Energy Drinks

Drink (/100 ml) CHO (g) Na (mg) Caffeine (mg)Red Eye (Classic) 14.8 <0.1 10Red Eye (Xtrm) 14.8 <0.1 10Red Eye (Gold) 15 <0.1 10Red Eye (Platinum) 11.3 <0.1 10Upper E 12 <5 -V 11.2 97 20Average 12 24 20.2ACSM Guidelines4-8 50-70 -

Competition Strategies

Pre-Event Meal

• 2-4 hr prior• High in carb• Low in fat• Moderate protein• Moderate fibre• Adequate in fluid• Familiar and

tested

Staying Cooled and Fuelled

• Check fluid intake• Check body

weight• Monitor urine

volume & colour• Replace fluids and

energy regularly

A Recipe for Recovery

Carbs and fluids immediately after exercise

Muscle Glycogen storage in the vastus lateralis muscle during the first and second two hours of recovery when

carbohydrate was consumed immediately after exercise or two hours after exercise.

Adapted from Wheeler et al., 1989

Recovery Time (hr)

GlycogenSynthesis

( mol/gm wet wt)

0

5

10

15

20

0 - 2 2 -

Immediately after exercise

Two hours after exercise

4

How can I Speed up Recovery?

• Eat carbs immediately after exercise

• Consume approximately 1 g per kilogram for first hour

• Follow with a high carb meal• Liquid carb sources can be useful

Useful Resources

• www.ais.org.au/nutrition (links)• www.sportsdietitians.com• www.coachesedge.com• www.gssi.com• www.msse.org (scientific)• Books available from Sports

Dietitians Australia (see site above)

Common Questions