Sports
Nutrition
by Dante Dettamanti,
BS, MS
Does Diet Make a Difference in Your Performance?
YOU BET IT DOES!
As mentioned in the last months article on “Nutritional requirements for water
polo players”, the foods that you eat provide the potential energy, or fuel, that
your body needs in three forms: carbohydrate, fat and protein. Consuming
enough calories, or fuel, each day is the key if you want to perform well in
practice and in games. But the more arduous the activity, like water polo, the
more important it becomes to consume the proper mix of the three energy
supplying nutrients. All three are important for the water polo athlete; but the
primary limiting factor in performing water polo in practices and games are
CARBOHYDRATES!
This article will be devoted to learning what kinds of carbohydrates to eat, when
to eat them, and how to restore them in your body after you have used up the
supply that is stored in your body. (Proteins and fats will be discussed in next
month’s article). Carbohydrates, such as sugar and starch, are readily broken
down into glucose, the principal energy source of the body. Glucose can be used
immediately, or it can be stored in the muscles and liver as glycogen. During
exercise, glycogen is converted back into glucose and can be used a fuel by the
muscle fibers. Not only is glycogen the most significant source of energy for
muscle contraction in high intensity exercise; but it is also a source of energy for
brain function both during rest and exercise.
If an athlete wants to train and compete efficiently, he needs a full tank of
glycogen every time he exercises. This can only come from food sources.
Frequent long and hard training sessions and games can reduce the amount of
glycogen available. The likely cause of poor performance and fatigue in practice,
or in games, is because of low levels of glycogen in the muscles. Studies have
shown that the glycogen stored in the body will start depleting after only one hour
of continuous exercise. It can be depleted completely if not restored through diet
and rest.
The limiting factor on performance, therefore, even during moderate intensity
exercise, remains the bodies limited carbohydrate stores. No matter how ample
your fat stores, after you deplete your muscle glycogen stores you will
experience fatigue to some degree, and be unable to maintain the pace and
intensity required in practice and a game.
Graph A below shows a hypothetical situation for a water polo player starting the
training week on Monday with a large amount of glycogen stored in his muscles
and liver. After completing a strenuous 2.5 hour water polo workout he will use
up a large portion of the glycogen that was stored. After eating a high
carbohydrate dinner that night and breakfast and lunch the next day, he can
restore a lot of the glycogen that was used up. However, he will not completely
restore the full amount, and will consequently start the next day’s practice with
less than he had the previous day. This cycle is repeated every day, until about
the fourth day, when the glycogen is almost completely depleted. Now what
happens if you have another practice on Friday and a game on Saturday. How
well do you think you will perform in that practice and game if something is not
done to increase the amount of stored glycogen that you start the game with?
GRAPH A: Depletion of glycogen after four days of intense practice
HOW DO YOU RESTORE THE GLYCOGEN LEVELS IN THE BODY?
There are only two ways to restore the glycogen levels in a body. Burn less
calories (glycogen) by resting with easier training sessions; and/or by eating a
carbohydrate rich diet. A case in point for a high carbohydrate diet was a study
done with Ice Hockey players, a sport very similar to water polo in terms of
intensity and burning energy. As in a water polo game, muscle carbohydrate
(glycogen) is a major source of fuel; and declines anywhere between 38 and 88
percent. Muscle glycogen depletion relates closely to muscular fatigue.
A motion analysis of elite hockey players showed that the players with a high
carbohydrate (60% of total) diet skated not only 30% more distance, but also
faster than the players who ate a standard low-carbohydrate (40%) diet. In the
final period of the game, when a team either wins or loses the game, the highcarbohydrate group had more energy and skated 11% more distance than they
did in the first period. The low-carbohydrate group skated 14% less.
The bottom line in this and other studies of high intensity sports, is that both diet
(more carbohydrates) and rest are critical factors in performance. Resting for
several days and eating a low-carb diet was not effective in increasing
performance. Neither was a high carbohydrate diet and not resting. Both must
occur for maximum restoration of glycogen and maximum performance to occur.
Water polo coaches should take note. If you want your team to perform well in an
important game, then you had better rest them a few days by cutting back on the
length and intensity of your workouts, along with encouraging the players to add
more carbohydrates to their diet.
HOW MUCH CARBOHYDRATE SHOULD YOU EAT?
Most athletes that perform strenuous physical activity for several hours daily
require a diet that is high in carbohydrates, a minimum of 55-65 % of the total
food intake. Player’s diets should also include about 20-30 % protein for muscle
and enzyme build up, and about 20 % of the good mono and poly-unsaturated
fats. How much carbohydrate should you eat? Plenty, if you are a water polo
player who trains several hours a day of high intensity exercise. Most adults eat
only 150-250 grams of carbohydrate a day. That might be OK if you are
sedentary. That is certainly not enough to fuel an athlete’s body.
Most elite athletes need a lot more than the normal person, probably anywhere
from 400-600 grams a day, depending on your training level, intensity and
amount of training, gender, size, etc. Most water polo players, performing at a
high level of training for ten-plus hours per week, will need about 3-4 grams of
carbohydrate per pound of body weight. So, if you weigh 150 pounds, you will
need between 450 to 600 grams per day of carbohydrate
WHAT SHOULD I EAT AND WHEN?
Just to give you an idea of what a gram of carbohydrate is, consider that a
banana has about 20 grams, a large potato has 30 grams, a cup of fruit flavored
non-fat yogurt has 24 grams, a sandwich with a lot of bread and some lean meat
has 50 grams, while a plate of pasta has about 80 grams. Other good sources of
carbohydrates include whole wheat breads and cereals, rice, beans, corn, fruits,
and fruit bars.
It seems that it might take a lot of eating to get to 450-600 grams. There are
several ways to accomplish this feat! One trick is to cut back on fatty foods to
make room for more carbohydrates. Fats have a tendency to fill you up, and
should be used sparingly. Instead of piling on tons of cheese and meat sauce on
top of your pasta, eat the pasta with tomato sauce and sprinkled with a little
parmesan cheese on top. Instead of eating french-fries that are loaded with
saturated fats, eat baked potatoes or sweet potatoes and go light on the sour
cream and butter. Milk is a great source of calcium and fairly good source of
carbohydrates, but drink 1-2% fat milk or non-fat milk instead of whole milk.
EAT AFTER TRAINING
Try eating within two hours after training. This is the time when the body is more
acceptable to carbohydrates and has the ability to store more glycogen in your
muscles and liver. Eating after training is not always easy to do, especially if your
team has an early morning training session, and you have to go to class right
after training. Bring some food with you to morning practices for eating after
training; something that you can carry and is easy to digest.
Fruits like bananas and apples, and food-bars are easy to carry; or if you can
stop at a fruit/smoothie bar and get a fruit smoothie. Smoothies are a great
source of carbohydrates, they go down quickly, and they digest quickly. Watch
the ones that are high fat though. Many fruit/smoothie bars will list the ingredients
in their smoothies, and will also list the percentages of fat, carbohydrates and
proteins. Pick the ones with the most fruit and the least amount of fat.
Food bars (sport/energy bars) are a great way of meeting some of your
carbohydrate needs and are easy to carry with you in your backpack. Make sure
that you get high carbohydrate/low fat bars. Read the label and apply the 4 and
20 rule. Any bar that provides more than 20 grams of carbohydrate and less than
4 grams of fat is a good choice. Also, make sure that you drink water with your
food bar to aid in digestion. If you can’t meet your carbohydrate needs with three
meals a day, try snacking between meals with food bars, fruit, fruit muffins, half a
sandwich, anything that you can think of that provides some carbohydrates.
Remember that food bars are to be used as a supplement to your meals, or as a
snack food; not as a complete meal. Don't overdo it with these bars and think that
you can eat many of them every day, and not eat any other necesary foods. One
or two a day as an in-between meal snack, under the guidelines as described
above, should be the maximum for an athlete.
SKIPPING MEALS OR ADDING MEALS
Water polo players should be adding meals rather than skipping meals. Three
meals a day plus two light snacks should maintain the proper amount of
carbohydrates for the water polo player. The meal that is missed the most is
breakfast, especially if the team has an early morning practice session. It is
difficult to eat breakfast after a morning workout. There simply is not enough time
before you have to rush off to class. If that is the case, athletes should carry food
in their backpack that they can eat quickly. Sports bars, fruit, muffins, and sports
drinks with some sugar and no caffeine are good sources of quick carbohydrates
for a rushed breakfast.
HOW DO I KNOW IF I AM NOT GETTING ENOUGH?
There are several ways of determining if you are getting enough carbohydrates.
Probably the best way is how you feel. Everyone gets fatigued during a hard
practice or game; but if you are still fatigued at night or the next day, if your
performance in practice and games is lacking, if you aren’t mentally alert, if you
are tired all of the time and you can’t seem to keep your weight at a normal level,
then you probably need more carbohydrates in your diet.
If eating more and adding snacks doesn’t work, then you might consider
carbohydrate supplements. Supplements are available as gels and in liquid form.
Marathon runners or tri-athletes that train many hours a day, and who start losing
a lot of body weight usually use them. When the body runs out of glycogen, it
turns to fats and proteins as a source for producing ATP. Burning fats is not
much of a problem; but burning protein can be. Utilizing body protein means that
a person is essentially using muscle tissue for energy. Not what an athlete would
want if he wants to perform well.
During a ten-hour triathlon race, the body cannot store enough glycogen to get
through the entire distance. So, many tri-athletes ingest high-glucose gels, or
other high carbohydrate sources, during the actual race. Water polo players
probably would not need this kind of supplement during a game or practice; but it
might be a way to replenish your carbohydrates between games, when you have
several games in one day. Pre-game and in-between game meals will be
discussed in a future article.
HOW MUCH WATER SHOULD I DRINK?
Yes, even if you are playing in a pool full of water, you can still sweat and loose
body fluids. Do you need to drink 8 glasses of water a day as some nutritionists
recommend? It depends on several factors: How hot is the air and water
temperature, how hard and how long you practice, and how much food you eat
that contain large amounts of water. Thirst is usually a good indicator of your fluid
needs; but when you are participating in physical activity in warm weather, you
might not feel thirsty.
Athletes should start drinking before they start feeling thirsty, and continue
drinking small amounts of water during training in warm conditions. The color of
your urine is a good indicator of body fluid needs. Yellow or yellow-orange color
indicates water stress, while nearly clear or light-yellow means that you are well
hydrated. Foods also can provide certain amounts of fluid in your diet. If you
keep track of your water needs and hydrate ahead of time in hot weather, you
should be fine. If you start to feel light headed or nauseous, then you are possibly
suffering from dehydration.
SPORTS DRINKS?
Sports drinks are not only a great source of carbohydrate to help fuel your
muscles; but also a great source of fluid for your body. Be careful that the sports
drink that you drink does not contain too much sugar. Drinks that are have more
than 8% sugar interfere with water absorption from your stomach. You may end
up with a full and bloated stomach and very little fluid in your body where it is
needed. Check the label. If it has more than 8 grams of sugar in 100 ml of
volume, then it is too high in sugar. Also, make sure that you are getting a sportsdrink and not an energy-drink. The energy from an energy-drink comes from
huge amounts of caffeine, and not a lot of sugar. Caffeine will not help you
perform better if you need more sugar to fuel your muscles.
DON”T JUST EAT, EAT BETTER!
Some athletes feel that they can eat just about anything they want and still
perform well in their event. This simply does not work! Athletes should educate
themselves about what they need to eat, what foods provide what they need, and
about the quality of the foods that they do eat. Things like eating whole grains,
instead of refined white grains add quality to your meals. Educating yourself to
eating right can go a long way in helping you achieve your peak performance in
water polo games. Don’t just take a chance by eating everything in sight and
hoping that everything will work out for you.
An example of this is a friend of mine who was going to compete in a triathlon.
He wanted to carbo-load the day before the race. Thinking that he was going to
have a high carbohydrate meal, he ordered a huge pizza with pepperoni and
double cheese. Little did he realize that of the 1800 calories in the pizza, 1200
calories were fat and protein from the pepperoni and the cheese, and only 600
calories of carbohydrate came from the tomato sauce and the dough? The fat
and protein contributed nothing to his triathlon as far as energy use (your
muscles need carbohydrates), and consequently he did poorly in his race. Many
months of hard training down the drain because he didn’t know what the effects
of eating the pizza were, and that only a third of the pizza contained muchneeded carbohydrates. Much less than he really needed.
Next month’s article will go into more detail on what an athlete should eat, and
how to go about eating nutritious meals.