Food for distance runners

From theory to practice

Wageningen - April 12, 2007

Theory in a nutshell

• Carbohydrates

• Fluids

• Sports drinks

• Basic nutrition

Theory: carbohydrates

• Most important substrate for performance (faster energy delivery than fats or proteins)

• Not just pasta, but also:– Rice– Potatoes– Cereals– Banana’s, etc.

• Energy bars

Theory: fluids

• More important than carbohydrates?

• Most important reason for decreased performance: dehydration (starts at ~ 2%!) and rise of core temperature

• Average max uptake per hour: ~ 1 liter

• Combination of water, carbohydrates and minerals: sports drink

Theory: sports drinks

• Before and during exercise: isotonic (or slightly hypotonic) thirst quencher: 60 - 70 g/l of CHO, minerals

• After exercise: higher concentration of CHO possible (‘energy drinks) - possibly in combination with peptides

• Uptake of at least 150 - 200 ml promotes gastric emptying

Theory: basic nutrition

• Fats and proteins are important, too!

• Basics first: it’s no use to spend time on details when the basics aren’t taken care of

• Enjoy good, fresh foods; enjoy your meals!

Theory practice

• Marathon– ‘Normal’ CHO (glycogen) stores in body are

not sufficient for 42 km– More than 2% of body weight is lost by

perspiration Drinking is necessary!– ‘Carbo loading’?

Practice: carbohydrates

• Variation in CHO sources. As mentioned: grains, pasta, bread, rice, bananas, potatoes.

• Fluid foods: ‘carbo loaders’ and fruit juices

• Mix soluble CHO with tea, yogurt, etc. E.g. ‘Fantomalt’ (maltodextrin); tasteless, colorless, soluble.

• Do not ‘over eat’

Practice: (sports) drinks

• Cool, not cold

• Taste!

• Drink during training runs

• Race: use the same drink you have been using in training

• Coffee (caffeine): only when you are used to drinking coffee, timing

Practice: (sports) drinks

• Temperature of drink: use warm water in winter, ‘old sock’.

• Concentration of drink: dilute in warm weather, concentrate when cold (within certain limits!)

• Marathon:– Start fully hydrated– Start drinking at first refreshment station

Supplements

• Overwhelming choice, little proof

• What I use: – Low-dose (50% RDA) multivitamin/mineral– Extra B- complex (50% RDA)– Fe, when indicated by blood tests

Final recommendations

• Timing: know when to take last meal• Never try new foods/drinks in a race; use

what you have been using in training• Never try to loose weight during last days

prior to a race• Abroad: bring your own foods. E.g. Japan,

March 2007: bread, cereal bars, sports drink