Monday, June 27, 2011

MARATHON; GOOD NUTRITION, GOOD RUNNER














There are 3 nutritionally related situations that may lead to a poor marathon performance, or even failure to finish the race.
These are:
Dehydration
Glycogen Depletion
Excessive Loss Sodium

The pre race fueling strategy must ensure that runners will have plenty of water, carbohydrates and sodium heading into the event and continuously throughout the event.

Most people, including athletes, are always on the edge of dehydration.

Dehydration results in a reduction of blood plasma. This turns the blood into a thick sludge and forces the heart and body to work harder to move it.

Under normal environmental conditions the body of a non exercising adult requires
    1 cup (250ml) water for every 6 - 9 kg body weight
    For example a 55kg person requires from 55/6 x 250 = 1.3 litres to 55/9 x 250 = 2.3 litres water per day
Add to that around 300 to 800ml per hour during exercise (actual amount dependent upon environmental conditions and individual requirements)
The day before a marathon, if you haven't already taken in 1.5 litres of water today , then begin by taking 5 - 6 sips of water every 15 - 20 mins. A MAXIMUM of 500 ml per hour. Spread out the water so the body has time to absorb it.
As much as it is important to be fully hydrated going in to the marathon, it is also EXTREMELY important not to overconsume water as this can upset our sodium balance in the blood.

Drinking too much water can dilute the amount of sodium in the blood. This can lead to a condition know as Hyponatremia.
Hyponatremia is the second condition where we may fail to finish a marathon and can be extremely dangerous.

Hyponatremia can occur any time you drink water faster than your kidneys can eliminate it.
It occurs when athletes lose sodium through sweat and are unable to replace it. They may drink water but do not replace the sodium.

Slow runners are more at risk than faster runners because they comsume fluids over a longer period of time.

It also appears that females are more at risk than males.
One trick many athletes use is 'Baked Rold Gold Pretzels'. (Village Grocer have them on sale this week for RM11).
6 - 10 pretzels the day before the marathon..........or just a little extra salt on the pre marathon day meal.......will help to balance the extra water nicely.

Glycogen Depletion

Glycogen is the form in which carbohydrate is stored in the muscle cells. It is a ready supply of energy.
Longer distance running burns carbohydrate and fat as fuel.
The faster you run the more carbohydrate you use.
The slower you run the more you are fueled by fat stores.
You can somewhat train your body to rely on more or less carbohydrate during your training runs by altering the type of nutrition you take in before, during and after the runs.
With the marathon this Sunday though, it is too late to look at this........another article.............
Many marathoners think they can 'carbo load' the night before the race by eating plateloads of pasta and high carb foods.
In reality, if you have already been eating a balanced diet the week before the marathon you have already loaded your muscles with glycogen.
The worst thing you can do for your marathon comfort is load up on huge plates of pasta and salad and high fat dressing and sauces.
You don't want the extra weight in your digestive tract in the morning.
You don't want any roughage - such as from salad.
Constipation is generally not a problem in marathon running - in fact it is usually the other way around.......if you catch my drift..........after long hard runs.

So: Eliminate high fibre foods and foods that cause gas the day before your run - beans, broccoli, bran, cereals
if you are lactose intolerant, eliminate all milk products.
If spicy food speeds up your gut then eliminate them.
Eliminate alcohol and reduce caffeine to the bare minumim.
Don't blow all your hard training by eating unfamiliar foods that may upset your system.
Try to eat a moderately sized dinner that is 'normal' for you, the night before the big run.

Day of the Marathon

Try to eat a breakfast of at least 300 - 400 Calories, 2 - 3 hours before the start of the warmup.
Whatever you choose to eat, again, it should be 'normal' for you and should have ideally been practiced in your long trainng runs. Preferable something on the bland side and easy to digest.
Example; Instant Oatmeal, 2 - 4 toast and nutbutter or some other type of protein , 1 - 2 bananas (if they don't repeat on you)
I like to make a blended ptorein smoothie (milk, 30g whey/cassein blend protein, banana or frozen blueberries all blended well).
Snack on 2 - 5 more pretzels
Drink a MAX of 500ml water 1 - 2 hours BEFORE the race start. Do not overdrink. This should start you off wel hydrated and give you enough time to eliminate and extra.

During Marathon

Ideally you need to supply water, carbohydrate and sodium during the run.
Water -
The International Medical Directors Association put out an advisory statement in 2002 stating that marathoners should drink NO MORE THAN 400-800MLS FLUID PER HOUR.
Standard Chartered KL Marathon has water provided in cups at the start and every 2 km after the first 4km.
Aim to drink 1 cup every station (10km per hour pace you will pass water every approx 12 mins)

Carbohydrates-

Aim to have an intake of 30grams carbohydrate every hour.
Power Gels provide 27g carb.
100+ Isotonic Drink provides 10grams carb every 150 mls cup.
100+ WILL BE AVAILABLE EVERY 4 KM AFTER THE FIRST 4 KM (IN CUPS)
Take 1 - 2 cups 100+ per hour PLUS 1/2 gel with 150ml water every 30 mins
DO NOT TAKE GEL WITH 100+
2 major considerations with gels
  • Too much gel and Too little water = High Carb Concentration
This will cause the carb to be absorbed slowly and may pull fluid into your gut, lowering blood volume and causing dehydration.
  • Too little gel and Too much water = Low Carb Levels
This wil result in not enough carbs in your muscles so that you may end up limping through the final miles of the marathon with sad glycogen depleted legs.
AIM TO TAKE 150 ML WATER AND 1/2 GEL EVERY 30 MINS PLUS 1 - 2 CUPS OF 100 + EVERY HOUR. GEL AND WATER COMBO AND 100+ AT DIFFERENT STATIONS
Sodium - Runners should try to take in 1 g sodium every hour. This is assimple as 2 - 3 Rold Gold Baked Pretzels. This is the equivalent of the sodium in 10 gels or 20 Saltine Crackers.

POST RACE NUTRITION


After the run begin by drinking fluids that contain carb, sodium and protein.

Chocolate milk is a great post race recovery drink (protein and carbs)
Have some 100+ for carbs and 2 - 3 more pretzels.

Eat and drink as much as you like taking in.

Do not drink only water as this may exacerbate hyponatremia.
It might be best to avoid fibre and spicy food.
Eat 3 - 4 times over the next 4 - 6 hours post race. Smaller meals are more effective at replacing glycogen and repairing muscle than big meals.
Aim to have meals with good carbs, good lean protein and healthy natural fat sources.........but personally, if you dont deserve a treat after a marathon when will you???? Just avoid alcohol!
Green Coconut Water is an excellent post race recovery drink.
March 2002 Journal of Physiological Anthropology and Applied Human Science found that drinking fresh coconut water to be more effective than drinking a carbohydrate electrolyte beverage or plain water as a way to rehydrate the body after exercise. Coconut water has potassium, calcium, magnesium, Vitamin C and has the same electrolyte balance as our own blood.
1 cup coconut water (green coconut) provides 600mg Potassium
Compared with
Small Banana (<6 inches) which provides approx 290mg Potssium

Any queries or questions pre/post race please leave comments below