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This page was last updated: 8/24/11
August’s Fitness
Makeover will focus on nutrition for the endurance athlete. A year ago, Bob
Petraglia from Boston, Mass., began swimming 800 meters three times a week
for fun and fitness. As most of us find, he was addicted to the endorphin
rush that his newfound exercise provided, and within six months Bob was up to
2,000 meters six times a week (with 3,000 meters on the seventh day).
This fall, he plans to race in the annual 2.4-mile Waikiki Roughwater swim,
and depending on how that goes, perhaps a five-mile swim in St. Croix.
These are ambitious goals for a relative newcomer to the sport, but having
spoken with Bob I’m confident that he’ll be crossing the finish
line in both events with no problem at all.
Bob had questions regarding his daily diet and how he could maintain or gain
back some of his weight; he has dropped 18 pounds since he started swimming,
only half of those pounds intentional and necessary.
At 5’9” and 152 pounds, Bob needs to be about 160 pounds,
according to Leigh Fish, MS RD, a Los Angeles-based registered dietician who
specializes in athletes (her boyfriend Josh also happens to be a triathlete
on the US National Team!).
Given that I am not a registered dietician or nutritionist, I have deferred
all advice that follows to Leigh — and have only served to break it
down into a reader-friendly article (and I’ve learned a few things from
our guest source in the process …so thank you, Leigh).
Bob writes that he feels healthier, more alert, and a lot hungrier than ever
before since he began swimming on a daily basis. This is natural, and he
needs to increase his intake of carbohydrates in a specific way to avoid
losing more weight — while sustaining the energy he needs for optimum
performance.
Most people assume that binge-ing on pasta, grains and breads is the best way
to gain the quick energy needed for endurance training. Wrong.
According to Leigh, Bob needs to keep his metabolism running all day long
with frequent snacking, and not just three large carbo-friendly meals.
“Eating only large meals may not give you the sustained energy that you
need for an intense swim workout, especially if your most recent meal was
more than two hours before the training session,” she explains.
“Although you wouldn’t want to have a large meal right before
your swim, a small snack which is mainly carbs, such as a cup of juice or a
half a granola bar, would be just right.”
Bob supplied me with a comprehensive daily diet breakdown of foods he eats
and snacks on (which I forwarded to Leigh), and vegetables were the only food
group that was somewhat neglected.
“Including vegetables in your lunch and dinner meals is very
important,” says Leigh, “because it allows you to eat a large
volume of food without a large amount of calories. Be sure to choose an array
of colors when eating fruits and vegetables, as this will provide you with
the multitude of vitamins and minerals that you need before, during, and
after your workouts. Remember, not everything comes in a pill, even if
it’s a multivitamin.” (Great advice, if you ask
me … like most people I know, I rely on vitamins more than I should
for my daily allowances).
Bob’s diet could also use more dairy, and Leigh recommends consuming it
after the tough workouts.
“Reloading with a protein/carbohydrate food is useful to replete any
glycogen stores that may have been lost in heavy training. Good options are a
glass of milk, low fat ice cream, cottage cheese, or yogurt.”
Bob’s consumption of protein is Herculean, with generous daily portions
of chicken, nuts, hamburgers, and tuna. Leigh reminds him that fish and eggs
are another protein source not to be overlooked.
Bob’s only apparent vice is a passionate addiction to Doritos. A
whopping five times a week at up to 10 handfuls a pop, this is the one area
that gave Leigh the right to slap our subject with a major meal makeover.
“‘10 healthy handfuls a day’! Now really, how healthy can a
handful of Doritos be? A good substitute here would be pretzels," Leigh says.
"In the meantime, weaning yourself off the Doritos would be a wise option
since your dependence seems to be so … immense! "Allow yourself
Doritos three times a week and limit your intake to two handfuls that fit
into a small bowl. If you want more, refill the bowl ... with pretzels!
Slowly, your dependence will just turn into a now-and-again indulgence.
Comment from the peanut gallery: My guilty pleasure is ice cream, and since
speaking with Leigh I’ve begun weaning myself off of those
easy-to-consume-in-one-sitting Ben & Jerry’s pints. Instead,
I’ve stocked my fridge with Ben & Jerry’s frozen yogurt, and
I now only allow myself a half-pint (served in a bowl instead of right from
the carton). Hopefully I’m getting my post-workout protein fix while
weaning myself off of those oh-so-good-but-oh-so-bad fat calories.
As far as monitoring his weight, Bob need only step on a scale once a week.
Daily scale-stepping will show minor fluctuations that can wreak havoc on
one’s psyche and contribute to hyper-self-analysis — not a good
road to go down.
Instead, a weekly weigh-in can give you a consistent reading that over time
will paint an accurate picture of where your body weight is, and should
be.
Bob is an avid vitamin- and mineral-taker, and although Leigh admits that
most people would rather rely on a pill for their essential needs, she stands
by her claim that there is no comparison to vitamins nd minerals gleaned from
real foods.
She does, however, suggest the occasional extra dose of Vitamin C and E,
given the endurance athlete’s above-average training intensity:
“Vitamin C and E are good antioxidants, especially for endurance
athletes who experience a great deal of oxidative damage during long bouts of
cardiovascular activity. It can’t hurt to take this, but also may not
be necessary each day.”
Finally, the last bit of wisdom that Leigh offered to impart to Bob (and
possibly to more than a few readers of this column), is the “if a
little is good, then a lot is better” misconception about protein
intake.
Given Bob’s healthy meat consumption discussed earlier, there is little
reason for him to boost his protein intake with powders and energy bars in
his between-meal snacks.
“Considering the intensity level that you are swimming, you need, at
the most, 1.2b/kg of protein per day," Leigh said. "For a 152-pound man, this
is only 83 grams of protein. 1 cup of milk for breakfast, 3 oz. of turkey and
1 slice of cheese for lunch, and 5 oz. of turkey for dinner provides about 87
grams of protein. Some protein powders in smoothies can offer up to 25 grams
of protein (and 100 calories), all of which are unneeded in Bob’s
case.”
Although the above overview is broad and has been written to apply to the
general active population, it is important to note that the feedback came
after a comprehensive analysis by a registered dietician. It was based on an
individual of a certain height and weight, with detailed specifics of the
subject’s diet plan. Anyone considering a drastic change to their
eating habits (for better or worse) is urged to consult a registered
dietician or nutritionist who can outline a plan to address each
individual’s specific needs.
Runners therefore need to do
everything in their power to accelerate muscle recovery after exercise.
First, in the first two hours after completing each workout, they need to
take in water, carbohydrate, electrolytes, protein, and antioxidants. This
will promote rapid rehydration, replenishment of muscle and liver glycogen,
and muscle tissue repair, and will reduce delayed-onset muscle soreness.
Runners should also stretch their running muscles immediately after each
workout, as this accelerates the removal of metabolic wastes from the muscles
and prevents tightening of the muscles.
And finally, at some point prior to the next workout, runners should engage
in self-massage to reduce tissue welling, increase bloodflow, and relieve
muscular adhesions and trigger points.
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"I'm training for a marathon ... I dread the long runs. I'm dragging after 12 miles. Any suggestions for how to boost my energy?"
"I'm whipped by the end of my after-school soccer practices ..."
Sound familiar? Preventing fatigue is the No. 1 concern of active people who exercise for more than an hour.
This article can help you enjoy high energy and enhanced stamina during long, hard exercise sessions. (For shorter exercise sessions, a pre-exercise snack and some water should fuel you well.)
To prevent fatigue during extensive exercise that lasts for more than 60 to 90 minutes, you have two nutrition goals:
1. To prevent dehydration
2. To prevent your blood sugar from dropping
The following tips can help you reach those goals.
Sweat and dehydration
When you exercise hard, you sweat. Sweating is the body's way of dissipating heat and maintaining a constant internal temperature (98.6°F).During hard exercise, your muscles can generate 20 times more heat than when you are at rest.
You dissipate this heat by sweating. As the sweat evaporates, it cools the skin. This in turn cools the blood, which cools the inner body. If you did not sweat, you could cook yourself to death.
A body temperature higher than 106°F damages the cells. At 107.6°F, cell protein coagulates (like egg whites do when they cook), and the cell dies. This is one serious reason why you shouldn't push yourself beyond your limits in very hot weather.
When you sweat for more than an hour, you lose significant amounts of water from your blood. The remaining blood becomes more concentrated and has, for example, an abnormally high sodium level. This triggers the thirst mechanism and increases your desire to drink.
To quench your thirst, you have to replace the water losses and bring the blood back to its normal concentration.
Unfortunately for athletes, this thirst mechanism can be an unreliable signal to drink. Hence, you should plan to drink before you are thirsty. By the time your brain signals thirst, you may have lost 1 percent of your body weight, the equivalent of 1.5 pounds (24 ounces) of sweat for a 150-pound person.
This 1 percent loss corresponds with the need for your heart to beat an additional three to five times per minute. This contributes to early fatigue.
Thirst sensations change with age and older people, even athletes, become less sensitive to thirst. For example, 56-year-old hikers became progressively dehydrated during 10 days of strenuous hill walking. The younger, 24-year-old hikers remained adequately hydrated. This means older people, in particular, should carefully monitor their fluid intake.
Light-colored urine, in significant volume, is a sign of adequate hydration.
Most athletes voluntarily replace less than half of sweat losses; thirst can be blunted by exercise or overridden by the mind. To be safe, always drink enough to quench your thirst, plus a little more.
If you know how much you sweat, you can then replace those losses according to a plan. To learn your sweat rate (and fluid targets), weigh yourself naked before and after a workout. For every pound (16 ounces) you lose, you should strive to replace 13 to 16 ounces (80 to 100 percent of that loss) while exercising.
This requires training your gut to handle this volume. Do not drink more water if your stomach is already sloshing; enough is enough!
You might find it helpful to figure out how many gulps of water equate to 16 ounces, and even set an alarm wristwatch to remind you to drink on schedule. You'll also need to plan on having the right quantity of enjoyable fluids readily available. Do not be in such a rush to start your workout that you fail to bring with you the sports drinks and fluids that will enhance your efforts.
Carbohydrates and blood sugar
As I?ve mentioned above, you can significantly increase your stamina by consuming a pre-exercise snack that provides fuel for the first hour of the workout and by drinking adequate fluids during exercise.
The third trick to enhancing endurance is to consume carbs after an hour of exercise. Depending on your body size and ability to tolerate fuel while you work out, you'll want to target 100 to 250 calories of carbohydrates per hour of endurance exercise.
The larger you are, the more calories you need. For example, if you weigh 180 pounds, you should target about 250 calories per hour, such as 8 ounces of a sports drink every 15 minutes, or a 250-calorie energy bar plus water.
During a moderate to hard endurance workout, carbohydrates supply about 50 percent of the energy. As you deplete carbohydrates from muscle glycogen stores, you increasingly rely on the carbs (sugar) in your blood for energy. By consuming carbohydrates such as sports drinks, bananas, or energy bars during exercise, you can both fuel your muscles as well as maintain a normal blood sugar level.
Because your brain relies on the sugar in your blood for energy, keeping your brain fed helps you think clearly, concentrate well, and remain focused. So much of performance depends on mental stamina; maintaining a normal blood sugar level is essential to optimize your workouts and boost your stamina.
Your body doesn't care if you ingest solid or liquid carbohydrates, both are equally effective forms of fuel. You just have to learn which sports snacks settle best for your body: gels, gummy bears, dried figs, animal crackers, defizzed cola, whatever.
Despite popular belief, sugar can be a positive snack during exercise and is unlikely to cause you to "crash" (experience hypoglycemia). That's because sugar feedings during exercise result in only small increases in both insulin and blood glucose. Yet, too much sugar or food taken at once can slow the rate at which fluids leave the stomach. Hence, "more" is not always better.
Because consuming 100 to 250 calories per hour of exercise (after the first hour) may be far more than you are used to taking in during exercise, you need to practice fueling while exercising to figure out what foods and fluids settle best.
You'll learn through trial and error which
snacks help prevent fatigue, boost performance and contribute to enjoyment of
your long, hard workouts
Athletes and protein: The truth about supplements
By Nancy Clark, MS, RD
Active.com 1/22/2003 Their goal: to convince athletes they need extra protein to build muscles and recover from exercise. Never before have I talked to so many frenzied athletes, bodybuilders and marathoners alike, who are worried their standard diets are protein-deficient and inadequate to support their sports program. They commonly ask: What's the best protein supplement? My response: Why do you think you even need a protein supplement in the first place? You can easily get the protein you need through standard foods. Believe it or not, very few athletes need any type of protein supplement. Yes, protein supplements can be helpful in certain medical situations. For example, an athlete with anorexia may be more willing to consume a protein shake than eat tuna, cottage cheese or chicken. Patients with cancer or AIDS often benefit from protein supplements if they are unable to eat well. But I have yet to meet a healthy athlete who is unable to consume adequate protein through his or her sports diet. Hence, the purpose of this article is to look at the myths and facts surrounding protein supplements, so you can make informed decisions regarding your sports diet. How much is enough? Only 10% to 15% of total calories need to come from protein. Although athletes require slightly more protein than does a sedentary person, a hungry athlete tends to eat hefty meals with large portions of protein-rich foods. That extra peanut butter sandwich, second chicken breast at dinner and taller glass of milk satisfies any and all protein needs without any supplements. Following are recommendations for a safe, adequate protein
intake:
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Breakfast: the most important meal of an athlete's day
By Nancy Clark, MS, RD
Active.com 2/12/2003
I commonly counsel athletes who skip breakfast, grab only a light lunch, train on fumes, gorge at dinner and snack on "junk" until bedtime. They not only rob their bodies of the nutrients needed for health, but also lack energy for high-quality workouts.
A satisfying breakfast tends to invest in better health than does a grab-anything-in-sight dinner. Sarah, a collegiate athlete, learned that fueling her body's engine at the start of her day helps her feel more energetic and also able to choose better quality lunch and dinner foods.
That is, when she has granola, banana and juice in the morning, as well as a sandwich and yogurt for lunch, she stops devouring brownies after dinner.
Excuses to skip breakfast are abundant: "No time," "I'm not hungry in the morning" and "I don't like breakfast foods." Weight-conscious athletes pipe up, "My diet starts at breakfast."
These excuses are just that, excuses; they sabotage your sports performance.
Here's a look at the benefits of eating breakfast. I hope to convince you that breakfast is the most important meal of your sports diet.
Breakfast for dieters
If you want to lose weight, you should start your diet at dinner, not at breakfast! For example, do not eat a meager bowl of Special K for your "diet breakfast." You'll get too hungry later in the day and crave sweets.
A bigger breakfast (cereal + toast + peanut butter) can prevent afternoon or evening cookie-binges. An adequate (500 - 700 calorie) breakfast provides enough energy for you to enjoy your exercise, as opposed to dragging yourself through an afternoon workout that feels like punishment.
If you are trying to lose weight, you should target at least 500 to 700 calories for breakfast; this should leave you feeling adequately fed.
To prove the benefits of eating such a big breakfast, try this experiment:
1. Using food labels to calculate calories, boost your standard breakfast to at least 500 calories. For example, add to your english muffin (150 calories): 1 tablespoon peanut butter (100 cal.), 8 oz. orange juice (100 cal.) and a yogurt (150 cal). Total: 500 calories.
2. Observe what happens to your day's food intake when you eat a full breakfast vs. a skimpy "diet breakfast." The 500+ calorie breakfast allows you to successfully eat less at night and create the calorie deficit needed to lose weight.
Remember: Your job as a dieter is to fuel by day and lose weight by night. Successful dieters lose weight while they are sleeping; they wake up ready for another nice breakfast that fuels them for another high-energy day.
Breakfast for the morning exerciser
If you exercise first thing in the morning, you may not want a big pre-exercise breakfast; too much food can feel heavy and uncomfortable. However, you can likely tolerate half a breakfast, such as half a bagel, a slice of toast, or a banana before your workout.
Just 100 to 300 calories can put a little carbohydrate into your system, boost your blood sugar so that you are running on fuel, not fumes, and enhance your performance.
You'll likely discover this small pre-exercise meal adds endurance and enthusiasm to your workout. In a research study, athletes who ate breakfast were able to exercise for 137 minutes as compared to only 109 minutes when they skipped this pre-exercise fuel.
After his morning workout, Jim, a banker, felt rushed and was more concerned about getting to work on time than eating breakfast. Using the excuse "No time," he overlooked the importance of refueling his muscles.
I reminded him: Muscles are most receptive to replacing depleted glycogen stores within the first two hours after the workout, regardless of whether or not the athlete feels hungry. I encouraged Jim to be responsible! Just as he chose to make time for exercise, he could also choose to make time for breakfast.
One simple post-exercise breakfast is fluids. Liquid breakfasts take minimal time to prepare and very little time to drink, yet they can supply the calories, water, carbohydrates, protein, vitamins and minerals you need ? all in a travel mug. (You can always get coffee at the office.)
Because Jim felt thirsty after his morning workout, he found he could easily drink 16 ounces of juice or lowfat milk. Sometimes, he'd make a refreshing fruit smoothie with milk, banana and berries.
Later on mid-morning, when his appetite returned, Jim enjoyed the rest of his breakfast: (instant) oatmeal, multi-grain bagel with peanut butter, yogurt with granola, a banana ? or any other carbohydrate-rich foods that conveniently fit into his schedule.
This nutritious "second breakfast" refueled his muscles, abated hunger and curbed his lunchtime cookie cravings.
Breakfast for the noon-time, afternoon and evening exerciser
A hearty breakfast is important for people who exercise later in the day. It not only tames hunger but also provides the fuel needed for hard workouts.
Research has shown that athletes who ate breakfast, then four hours later enjoyed an energy bar five minutes before a noontime workout were able to exercise 20% harder at the end of the hourlong exercise test compared to when they ate no breakfast and no pre-exercise snack. (They worked 10% harder with only the snack.)
Breakfast works! Breakfast + a pre-exercise snack works even better!
What's for breakfast?
From my perspective as a sports nutritionist, one of the simplest breakfasts of champions is a wholesome cereal with lowfat milk, banana and orange juice. This provides not only carbohydrates to fuel the muscles, but also protein (from the milk) to build strong muscles, and numerous other vitamins and minerals such as calcium, potassium, vitamin C, iron (if you choose enriched breakfast cereals) and fiber (if you choose bran cereals).
Equally important is the fact that cereal is quick and easy, requires no cooking, no preparation, no refrigeration. You can keep cereal at the office, bring milk to work and eat breakfast at the office. Breakfast is a good investment in a productive morning.
The bottom line
Breakfast works wonders for improving the quality of your diet. That is, eating breakfast results in less "junk food" later in the day. Breakfast also enhances weight control, sports performance, daily energy levels and future health.
Breakfast is indeed the meal of champions. Make it a habit ? no excuses!
Sample grab-and-go sports breakfasts
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Your muscles are most receptive to reloading glycogen in a 15- to 30-minute window immediately following exercise. Blood flow to muscles is enhanced immediately following exercise.
Muscle cells can pick up more glucose and are more sensitive to the effects of insulin, a hormone that promotes the synthesis of glycogen by moving glucose out of the bloodstream and into cells.
It takes at least 20 to 24 hours of refueling with carbohydrate-rich foods to replenish your muscle stores fully, so daily workouts can leave you running on low fuel stores. Since the effects of dehydration and muscle glycogen depletion can be cumulative, inadequate refueling can contribute to overtraining syndrome.
Here are strategies you can use to improve your recovery eating habits and make sure that you are always running on a full tank.
Don't forget fluids. Your body cannot perform any of its metabolic jobs well if you are dehydrated. Weigh yourself periodically before and after a hard workout to estimate how much fluid you need to replace. Remember, "a pint's a pound" ? every one pound lost during a workout reflects two cups of water loss. Sports drinks are an efficient fluid replacement since they also provide carbohydrates and sodium.
Fruit juices, low-fat milkshakes, and smoothies are also good choices since you get both liquid and carbs. Avoid drinking copious amounts of plain water if your workout has been over an hour. You'll need to consume some electrolytes and sodium as well.
After exercise, you can eat or drink your carbs, but do it quickly. Aim for about half a gram of carbohydrate per pound of body weight (about 50 to 100 grams) within the first 15 to 30 minutes after a long race or workout. Most sports drinks contain only 14 to 20 grams per cup, while fruit juices contain about 25 to 40 grams per cup.
The best recovery plan also includes eating carb-rich foods as soon as you can tolerate them. Try yogurt, fresh fruit, an energy bar, or a bagel. You may be able to boost the rate at which your muscles store glycogen, as well as speed up the recovery and repair of muscle tissue, by ingesting protein in combination with carbohydrate at this time. The results of one study suggest using one gram of protein per three grams of carbohydrate.
Try to eat (or drink) an additional 50 to 100 grams of carbohydrates every two hours until your next full meal. Think of whole grains, fresh fruits, dried fruits, pretzels, whole-grain cereal and non-fat or low-fat dairy.
Don't wait for your appetite to return after a long race. The longer you wait to eat, the less glycogen you store and the longer it takes to recover. Intense or exhaustive exercise may depress your appetite. Anticipate that, and have palatable food ready to eat.
Make notes about your food choices in your running log to help you keep track of what worked well and what didn't.
Maximize your potential
through mental training and focus
By Adam Zucco
UltraFit.com 7/2/2003
Principles of Focusing
Focusing Strategies
Breathing 101: Increase your efficiency for better oxygen uptake
By Thomas Chapple
UltraFit.com
9/3/2003
The diaphragm is the muscle located under the lungs that is designated to expand the lungs and bring air into them.
To breathe efficiently by using the diaphragm effectively, think about drawing air into the bottom third of your lungs as you expand your belly like a balloon.
Try doing this while inhaling through your nose and you'll notice a relaxing sensation throughout your body.
Take a few moments before each workout to sit quietly and practice breathing through your nose and with the diaphragm. This will start your workout in the right frame of mind and with correct breathing.
Keep reminding yourself how to breathe with the diaphragm throughout your workout, and return to it if you fall back on incorrect breathing.
Another breathing aid is to focus on exhaling forcefully during climbing and hard efforts. Once you've developed the habit of filling your lungs completely by breathing with the diaphragm, your body will take care of the inhaling portion on its own.
By forcing the air out of your lungs you'll develop a more complete, efficient breathing cycle. Short, shallow breaths don't completely fill or empty the lungs and will dilute incoming oxygen with carbon dioxide.
I've also found that airflow improves if I drop my jaw and open my mouth in an oval shape (vertically) during hard efforts
By June M. Lay
HealthNewsDigest.com 9/29/2003
Today we discuss "feeding our muscles" since the fuel we give our muscles plays an important part in being able to "smart weight train" and it's also an important factor in avoiding an injury. So, whether our goal is to tone, get strong, gain muscle, heal from an injury, or participate in a sport activity, we need to feed our muscles! Many of us think that if we eat lots of protein, we'll get lean, strong and we'll build muscle. Let me say now that it is the carbohydrates that we eat that gives us the energy to push the weights, to use the protein we do eat to build muscle. Those of us who participate in endurance sports such as running, cycling etc. know the importance of eating a diet high in carbohydrates with some extra protein. But did we know, for instance, that carbs are the foundation to our performance, whether to power our tennis game, aerobic workout, or bodybuilding routine? So, here are a few sport nutrition rules to "Feed our muscles": Eat enough and often enough When we eat enough calories and we eat often, we fuel our muscles, not just for getting around, but for all the additional activities, especially if we are active in sports. When we restrict our calories too much (this goes for us dieters) over a period of time, we send a signal to our body that a famine is coming. The body may then adjust our metabolic rate to slow down to conserve calories. Result? Most likely less strength, less energy, and even higher body fat! Eat carbohydrates Yes, let's eat the dreaded starches! When we eat enough carbohydrates, we give our muscles the fuel to work out hard. This in turn will give our body the need to utilize all that protein we're taking in to make more muscle (when we tone we add muscle fibers too, so this is not just for bodybuilders). Carbohydrates also feed our brain, so when our blood sugar levels are low from not eating enough carbs, we will impair our energy, focus, and performance. When we are in short supply of carbs, the process of turning protein into fuel for our muscles and brain is costly to our body. We impair our performance, our ability to build and repair muscle, our health and even our ability to lose weight (ever get constant sugar cravings after eating mostly protein?). Lastly, high-protein diets can cause dehydration. This is deadly to our energy. Drink water Water is stored in our muscles with carbohydrates. This is the energy source for our muscles. When we need to produce energy, the stored carbohydrates are used and water is released during the process. We need water to make and release energy. Guess what happens when we are dehydrated? We get fatigued easily. Water aids stamina and performance, and it helps to ward of those muscle cramps during intense exercise. Eat a balanced diet This means that for those of us who eat lots of protein, we also need to eat enough fruits, veggies and grains. And for those of us who are vegetarians, it is important to get enough protein, iron, calcium, B12, and Vitamin D. Supplements, sports bars and sports drinks are not a substitute for real food. Eat wisely I call this being choosy about what kind of calories we eat. If I want a tough workout, I will choose a nutrient-dense food over a junk food. Of course, there is always room for a little junk -- I recommend no more than 10% of our total daily calories (that's about 200 calories for most of us). So, if we want to look good, feel energetic, and perform well, let's "feed our muscles." Have we eaten enough carbohydrates; eaten often enough; eaten wisely and had enough water? If the answer is yes, we're off to a good start. |
By Deborah Shulman, Ph.D.
For Active.com 10/3/2003
"To give me energy." This is the usual response when I ask why someone has eaten an energy bar or other food in the hour or so before starting exercise. In fact, the opposite is true. Eating an hour or even half an hour before exercise is likely to make you feel tired and sluggish. Twenty-five years ago, if a food or drink label proclaimed "high energy," it would have sounded a death knell for that product. In contemporary times though, people interpret that to mean that it will give them high energy. Red Bull drinks proudly display that they are high-energy drinks. Sports bars are high-energy foods. Consequently, people eat or drink them so they have high energy during exercise. In the nutrition world, "high energy" is synonymous with "high calorie." The way that the body deals with high calorie, particularly high sugar, is by releasing insulin. Insulin is a storage hormone. When you eat a high-calorie, high-sugar food an hour before exercise, you will start exercise with high insulin levels. This has two important results. First, it will change how you perceive exercise. You feel sluggish and it feels hard. This is called the rating of perceived exertion, or RPE. Your RPE is higher when you start exercise with high insulin levels. Second, you will burn a lower amount of fat for fuel. Insulin lowers fat removal from the fat deposits and reduces fat metabolism inside the muscle. Consequently, you rely more on carbohydrate for energy. Obviously, if you are trying to increase fat metabolism, it is counterproductive to eat an hour or half an hour before exercise. In general, during the day, it is better to time your last meal or snack to be two hours before the start of exercise. If you wait too long, however -- say, three or four hours after eating -- you'll spend the whole exercise session hungry and fantasizing about food. In fact, the best time to exercise is after an overnight fast. At his time, blood levels of fat, growth hormone and testosterone are all high. Under these conditions, fat metabolism will be at its highest. Even better if you've had some coffee beforehand. Those who have low fasting blood sugar in the morning may want to eat a banana, a sports gel or some juice within five minutes of starting exercise. You know who you are: you feel dizzy and shaky in the morning until you've had something to eat. If you eat a small amount a few minutes before starting, you won't get a substantive insulin response. Instead of eating before exercise, eat within 30 minutes of finishing your exercise session. It is common for people to make the mistake of not eating after exercise, either because they think the increased metabolic rate will help them lose weight or just because they're not hungry. In reality, during exercise you are breaking down protein from the muscles, liver and kidney. This catabolic state persists after exercise. The more intense the exercise -- such as a heavy strength training session at the gym or an interval workout at the track -- or the longer the exercise lasted, the more muscle breakdown will occur. This when insulin is your friend. Insulin is a growth hormone and stops muscle breakdown. This is the best time to get larger doses of carbohydrate. Your glycogen storage tanks will be low and the combination of insulin and carbohydrate will refill them to be ready for the next exercise session and will help your muscles grow. |
By Dr. Don Kirkendall
For Active.com, 10/24/2003
Think nutrition is an easy topic? See if you have the answers to
these myths common in soccer.
1. Your performance in a game is not affected by what you eat You would think this is true, from reading the scientific literature on just what soccer players eat. Nutritional recalls from the 1970s to the present show that soccer players choose a diet that is around 40% carbohydrates, 40% fat and 20% protein. Virtually every study on athletic performance, be it a team sport or an individual endurance sport, shows that a diet rich in carbohydrates improves running performance. The more carbohydrates you eat, the more and faster you run, especially late in the game. What is discouraging is that in the very early '70s, the Swedes showed that soccer players with low muscle fuel (glycogen) walk about 50% of the game. And that was 30 years ago. What might be even more discouraging is that over half of a national team in the 1994 World Cup thought food had nothing to do with their game. Players eat what is put in front of them. 2. Sports drinks are just a product of marketing; they are no better than water No question that water is well understood by the active public. The days of fluid restriction during sports are long gone. But researchers have been looking at improving on water ever since the advent of Gatorade. The timing, volume, temperature and components of sports drink have been under continual study. For example, a drink does no good if it stays in the stomach, so the concentration of sugars is limited. A drink does no good if it doesn't get from the small intestine into the blood, so there is an optimal concentration of salt in the drink. And a drink isn't all that effective if it doesn't stay in the body -- meaning that the volume of drink and salt concentration, again, are critical. Plain water doesn't have these advantages. A well-formulated drink has the proper concentrations of sugars, salts, and micronutrients, making it more effective than water alone. 3. All sports drinks are alike, so just buy any of them A lot of people think this, and the marketing of different drinks can lead to this perception. But a close look at labels will show vastly different drinks. To start with, there are basically three completely different types of drinks: fluid replenishment drinks, carbohydrate replenishment drinks and energy drinks. Fluid replenishment drinks are formulated to provide optimal concentrations of sugars and salts, leading to rapid absorption and retention of fluids in order to prevent dehydration and improve performance. Carbohydrate replenishment drinks are designed to provide a fast source of carbohydrates that are rapidly absorbed by the intestines. These can be used during a game for extra fuel as well as right after play to start storing energy for the next day or game. The best drinks have a little protein in them that speeds the uptake and deposit of fuel into the muscle. Energy drinks are highly caffeinated drinks that deliver a small bump in energy due to caffeine's effect on the central nervous system, not by adding any more fuel to the muscles. Plus, caffeine is a diuretic, so it can increase urine volume, and any urine loss of water during exercise is not good. 4. It doesn't matter what players eat after games I go to games and tournaments and see some of the worst post-game feedings possible: soda, sweet drinks in soft packaging, potato chips, other salty snacks, chocolate, fries. You've seen it. The smart team supplies food that will start refilling the muscles with carbohydrates at just the time that the muscles are most ready to receive a fresh supply of fuel; the first hour to two after exercise. And that food probably doesn't come in a bag. A good supply of carbohydrates is needed, and it can come from a carbohydrate replenishment drink or other high-glycemic foods like bagels with jam/jelly, the ingredients for "chex mix" (not the premixed boxes from the store, but the ingredients minus the oil and toasting), pretzels, raisins (or other dried fruit). This is even more critical between tournament games when time is even shorter. 5. All athletes get enough protein from what they eat, so there's no need to look for other sources While most every survey of the athletic diet shows that they get all the protein they need from food, there is a problem. The vast majority of protein is consumed in conjunction with fat. Marbled meat, ground beef, fried chicken in the skin all are examples of protein that is combined with lots of fat. Red meat should be trimmed of fat, ground beef should be very lean, chicken should have the skin removed. But one place protein is often lacking is the immediate post-exercise meal. A little protein helps in storing new fuel in the muscles faster than when there is no protein. You can try to figure out a protein source (NOT from a fast food chain) or simply buy one of the carbohydrate replenishment drinks that contain protein. 6. I just coach; what the players eat is their problem While I have already stated that most all studies show that players are not eating properly, there is an implicit question. Who tells the athlete what to eat? There have been plenty of surveys asking where athletes get their information and the top two sources are the coach and teammates. Now, from what we know, teammates are probably pretty unreliable. That leaves the coach as the primary source of information. But should the coach tell the player or the parents? As the player eats what is put in front of them, that means the parents are now the assistant coach in charge of fuel. They need to know what to serve and when to serve it. Your new assistant may think the various versions of the Atkins diet are good for themselves, but those high-protein diets do the athlete no good when it comes to providing fuel. Make sure your parents know the facts. 7. Your body is the best indicator of when to drink Now, that is true ... if you are a donkey, or a dog. The thirst mechanism of humans isn't as good.In fact, the human thirst mechanism doesn't even kick in until you have lost about 2% of your body weight from sweating; a level where performance decrement begins to become evident. Drink early (before play), every 15 - 20 minutes during play, and at halftime. Put water bottles along the sidelines, in both goals, supply during stoppages. Remember that playing in the cold is also dehydrating, so don't forget to push fluids even in cold weather. There are likely more myths coaches, players and parents may be following, but by following some of the guidelines mentioned here will put your team at a significant advantage over the opposition. Copyright 2002 © Donald T. Kirkendall |
If you do them, you will have plenty of energy and less leftover muscle soreness by the time you practice again. If you don't do them, you might stay sluggish and tender a lot longer.
Nutrition tips
Nutrition is an important part of recovery. Nutritional recovery has three components:
1. Rehydrate
After games, you need to put these substances back into your body, in a little greater amounts than what you lost, sooner rather than later. Until you rehydrate, your body will have a hard time keeping cool and you may be prone to cramps and other problems.
Drinking water is just a start because it does not contain electrolytes. You're better off drinking a sports drink that has both water and electrolytes. Try to drink at least 12 ounces of sports drink in the first half-hour after the game ends. If it's a hot day, you may need to drink even more.
The goal is to drink 1.5 pints for every pound of weight lost over the next 24 hours, before the next workout. Your urine should be no darker than diluted lemonade.
2. Re-energize
It's important to quickly replace this carbohydrate. Until you do, you will not have much energy. Most sports drinks contain carbohydrates, so a convenient way to put energy back into your body is to get it from the same place you get your water and electrolytes.
You can also get carbohydrate from foods like fruits, breads, starches and certain vegetables. Muscles refill with carbohydrate the fastest immediately after exercise. Don't wait even as little as two hours after exercise to start, as the rate of refilling becomes slower.
3. Rebuild
Most sports drinks do not contain protein, but some of the new ones are adding it. Using a sport drink with protein is a good way to go because of the convenience. You can get the water, electrolytes, carbohydrate, and protein you need for recovery all from one source.
You can also get protein from foods like meat and cheese, but these foods also tend to be high in fat. When you eat a lot of fat after hard exercise, or even too much protein, it takes longer for the nutrients to get through your system to your muscles. This slows down the whole recovery process.
So a sport drink that contains protein is a better choice for post-game nutrition. It contains everything your body needs to bounce back fast, and without anything unneeded to get in the way.
Get a head start on recovery
Using a sport drink with protein during games is also a good idea for two reasons. First, it will delay fatigue so you can play harder, longer. In one experiment, athletes who drank a sports drink with protein were able to exercise 24% longer than athletes who drank a regular sports drink with no protein.
Second, the protein in the drink will reduce the amount of muscle protein breakdown that happens during the game, so there is less rebuilding to be done afterward.
Other tips
While your muscles are still warm after a game, stretch your muscles. This will keep your blood flowing, helping to deliver nutrients to your muscles and to clear away built-up wastes. You can start drinking your sports drink while you stretch. Later in the day, you can massage your legs using your thumbs, and this will also help with blood flow.
After you play a game, try not to do anything too strenuous for the rest of the day. Your body requires rest in order to rehydrate, re-energize, and rebuild the muscles. At the very least, be sure to get plenty of sleep that night. During sleep, your body releases hormones that help your muscles rebuild.
The recovery checklist
After every game:
"My diet is so boring ... I eat the same foods every day.""The waitress at the cafe no longer asks me what I want for breakfast -- she knows I'll have black coffee, orange juice and a toasted bagel without cream cheese."
"Is it bad to eat the same foods day after day?"
Many athletes eat the same foods every day, day after day, for years. Their typical menu is based on bagels, turkey breast, pasta, chicken breast, frozen yogurt and pretzels.
This repetition keeps life simple, eliminates decisions, and feels safe -- safe from "getting fat" by eating foods with unknown calories, as well as safe from eating the "wrong food" that might contribute to digestive upset while exercising.
The benefits of eating a variety of foods
Some athletes are content with their self-described "boring diet." But if you eat a repetitive diet and wonder about the healthfulness of this pattern, you might want to think about the benefits of eating a variety of foods. Here's why:
You'll consume a wider variety of nutrients. For example, if your only fruit is apples, you'll fail to get the folic acid that's found in oranges. If your primary protein source is chicken breast, you'll miss out on the iron and zinc that's better found in beef.
You'll reduce the chances of getting excessive amounts of a food that might be harmful. For example, if the grapes you eat every day have a bad pesticide on them, you'll consume a higher dose than if you were to alternate grapes with bananas, oranges and kiwi. Or, if you eat several nutrient-fortified energy bars every day, you might get too much of one mineral, which could create an imbalance with other another mineral eaten in smaller amounts.
You'll reduce the need for supplements. Eating many types of foods makes it easier to consume more of the 600-plus known compounds that food offers -- including the 13 known vitamins and 22 essential minerals, and numerous other minerals, phytochemicals, fibers and health protectors found in whole foods. Whole foods offer more nutrients, and better absorbed nutrients, than pills. For example:
A tale of two diets
Because eating a variety of foods is so important, the nutrition professionals in Australia launched a food campaign to encourage Australians to eat 20 to 30 different foods a week. Currently, most Australians eat only 15 to 18 different foods. I'd dare say the same holds true in this country (if not fewer different foods)!
Let's count the number of foods typically eaten by two types of active people:
Diet profile #1: The weight-conscious exerciser
1. Oatmeal
2. Turkey breast
3. Pita bread
4. Lettuce
5. Tomato
6. Rice cakes
7. Apple
8. Energy bar
9. Yogurt
10. Grilled chicken
11. Sweet potato
12. Broccoli
Oops! That's only 12!
Diet profile #2: Junk-food junkie
1. Coffee
2. Big Mac
3. Coke
4. Chocolate-chip cookies
5. M&Ms
6. Pizza
7. Chinese fried rice
8. Ice cream
9. Potato chips
10. Beer
How many of these items even count towards "real" food?
What's your number?
Now, it's your turn to do your math. For the fun of it (and education as well), write down what you eat for a week and count the number of different foods you consume. How did you do? If the number looks grim, here are some tips for enhancing food variety:
Bread: Select from a variety -- pumpernickel, rye, whole wheat, multi-grain, sunflower seed. Top with jam, peanut butter, almond butter, low-fat cottage cheese, light cream cheese.
Sandwich fillings: There's life beyond turkey breast! Lean roast beef (the kind you can get in a deli) is a fine alternative -- and offers far more vitamins and minerals. Peanut butter provides positive fats that lower the risk of heart disease. Tuna with light mayo is OK, as is hummus.
Snacks: Be creative and bypass yet-another rice cake, pretzel or energy bar. How about almonds and dried fruit, yogurt with granola, an apple with low-fat cheese, vegetable soup with rye crackers or graham crackers with peanut butter? Target two foods per snack (and three-plus foods per meal).
Consider cutting back on energy bars that are little more than sugar-coated vitamin pills with a little added protein. They commonly lack fiber and phytochemicals -- the important components of the fruits they tend to displace from the athlete's snack menu.
Pasta: Plain pasta isn't a vitamin-packed food. Pasta meals get their nutritional power from the tomato sauce on top, the veggies on the side, and the accompanying protein in the lean beef, turkey, tofu or beans added to the sauce. Round out the pasta meal with low-fat milk, salad (lettuce, carrot, pepper, tomato), crusty whole grain bread, and berries for dessert. You'll enjoy a 10-food sports meal that invests in both performance and health!
Sports nutritionist Nancy Clark, M.S., R.D., counsels both casual and competitive athletes in her private practice at Healthworks (617-383-6100), the premier fitness center in Chestnut Hill, MA. Her best-selling Sports Nutrition Guidebook, Food Guide for Marathoners and The Cyclist's Food Guideare available at www.nancyclarkrd.com or www.sportsnutritionworkshop.com.
It's difficult to find a body builder who doesn't rely on some form of protein or amino-acid supplement, and attributes their success to these products. These athletes in particular consume much more protein than they need.
Because this higher-than-necessary consumption of protein can offset the intake of other essential energy nutrients (carbohydrates), it's not surprising that many athletes struggle with low energy during a workout.
All nutrients (carbs, protein, fat) get converted to energy in the form of adenosine triphosphate (ATP), but each nutrient has unique properties that determine how it gets converted to energy.
It's important to clear up the misconception that protein is a ready source of energy, and uncover the real value of protein: recovery.
Carbohydrates: Efficient energy
Carbohydrate is the main nutrient that fuels moderate to high-intensity exercise. Fat fuels low-intensity exercise for long durations. Once stored carbohydrate is used up, glycogen depletion occurs -- more commonly known as "hitting the wall" or "bonking."
During exercise, this can be avoided by simply replenishing carbohydrate stores (eating easily-digestible carbohydrates during exercise that lasts more than 90 minutes). But glycogen depletion can also occur after several days of limited carbohydrate intake -- it's like going into your workout on an empty tank of fuel.
Limiting carbohydrate intake forces the body to rely on fat metabolism for energy production, which is far less efficient and will limit performance. The main function of protein is to maintain and repair body tissues and isn't normally used to power muscle activity. But if carbs and fat aren't available, then the body will rely on protein as a last resort in order to satisfy energy requirements.
Protein balance and overload
Dietary protein is comprised of building blocks called amino acids. Once dietary protein is broken down into amino acids, they join together to synthesize the particular protein the body needs such as hair, nails, hormones, enzymes and muscles. The liver is the central processing unit of protein, monitoring the needs of the body and synthesizing the particular proteins from the amino acids.
The by-product of protein synthesis is nitrogen in the form of ammonia (NH3), which is converted to urea by the liver and extracted from the body by the kidneys in urine.
The consumption of too much protein has a negative impact. As ammonia builds up it's removed as urea, which offsets the pH balance of blood causing an acidic environment. The kidneys have to work overtime, using fluids to flush the nitrogenous ammonia from the blood in order to stabilize pH. This process increases the risk of dehydration. Excess dietary protein has also been shown to cause an excretion of calcium in the urine. Both dehydration and loss of calcium are detrimental to athletic performance.
Furthermore, too much protein upsets macro-nutrient balance, displacing the intake of carbohydrates and fat and causing the body to rely protein as a fuel. While protein can supply energy, it wastes valuable resources and results in a number of undesirable effects.
Nitrogen balance is reflective of the dietary intake of protein being balanced by the excretion of urea wastes. If nitrogen excretion is greater than the nitrogen content (protein) of the diet, one is said to be in negative nitrogen balance. This usually is indicated by the breakdown of muscle tissue.
If the nitrogen excretion is less than the content of the diet, a positive nitrogen balance is achieved and is indicated by the formation of protein. The resulting tissue formation, as such, allows repair and recovery from exercise.
Pre-workout protein recommendations
In general, a low-fiber, low-fat combination is recommended as a pre-workout fuel source because it's digested more quickly and thus reduces the risk of gastrointestinal distress. A small amount of protein combined with carbohydrate is fine before a workout, but too much protein isn't recommended.
Protein digestion is much slower than carbohydrate, so a protein-only meal may not be fully digested, causing water to be rapidly absorbed into the intestinal track. This increases the risk of gastrointestinal distress during exercise, so it's important to avoid a large protein meal several hours pre-exercise.
Protein for recovery
Research has shown that some protein consumed with carbohydrates shortly before and after exercise does help the body recover faster by initiating muscle repair and growth. Adding protein to a recovery meal doesn't enhance the muscle's ability to store energy, but it does stimulate the muscles to rebuild. Relatively small amounts of protein are required for muscle repair. Therefore, athletes should consume a combination of carbohydrates and protein post-exercise.
Carbohydrates are used to refill the muscles with fuel, while protein is used to help build and repair muscle tissue. Within the scientific community, the optimal ratio of carbohydrates to protein in the recovery process is still debated.
Based on experience and experimentation, most endurance athletes find a ratio of 3:1 carbohydrate to protein works best. This is a general recommendation, so athletes should be aware of their individual differences; a little more or a little less might work optimally for each individual.
Nutrient recovery guidelines
A generalized equation can be used to determine recovery requirements. Most athletes need to consume .5 grams of carbohydrate per pound of body weight every two hours for six to eight hours after a workout. Therefore, if you're consuming 240 calories (60g) of carbohydrate after a workout, with the generalized ratio of 3:1 (carbs to protein), 80 calories (20g) of protein should also be consumed.
Here's an example of the calculation for a 150-pound athlete:
If you prefer to refuel with solid food, here are some healthy options:
Ilana Katz has a master's degree in dietetics with an emphasis in sports nutrition. She enjoys working with athletes of all levels, and specializes in body composition and weight management specific to individual needs. She participates in many endurance and team events in order to relate personally to her clientele. Ilana is The Sport Factory's head nutritionist, has worked with many local celebrities, and is the founder of the nutrition program IndiFITualize. Listen to Ilana on the Bertradio show (Q100) as well as Dave FMin Atlanta.
1. Water is the medium for metabolic activity.
In order to properly metabolize the calories ingested during activity, an
athlete needs to be hydrated. Even a slight level of dehydration, just one
percent (1.5 lbs for a 150-pound athlete), can contribute to a five-percent
decline in metabolic efficiency.
What does this mean for the athlete? First off, the calories being ingested, especially solid calories, will be left in the stomach rather than being distributed to the working muscles, leading to premature muscle fatigue.
Any fluids ingested will collect in the belly until there's a proper concentration for digestion. This leads to a shortage of fluid being directed to working muscles, and results in muscle cramping. During a high-impact activity, all the food and fluids left in the belly will be jiggling around, leading to uncomfortable side stitches, nausea, vomiting and diarrhea.
2. Water is a lubricant for our muscles and joints.
Noticeable muscle aches/pains/cramps can occur at the slightest bit of
dehydration and become debilitating as dehydration becomes more severe.
Headaches are also a common complaint.
3. Water helps cool the body
Water can be compared to the coolant we use in our cars. When the coolant
runs low, our cars overheat. Our bodies perspire in order to lower our
internal temperature; as blood flow to the skin increases the internal heat
generated evaporates through sweat. An athlete may have a flushed or blotchy
appearance.
As dehydration becomes more severe, this process becomes compromised causing core body temperature to elevate. The athlete may get the chills or goose bumps when the heat being generated isn't released from the body efficiently. If left untreated, dehydration can lead to heat exhaustion or heat stroke and potentially death.
For every percent drop in hydration, expect a three- to five-percent decline in performance. This is huge when you think about it -- it would be like adding an additional one to two minutes onto a 40-minute 10k runner's time. Thirst isn't a good indication of when an athlete needs to start drinking, as our thirst mechanism is initiated upon a three-percent level of dehydration which equates to a 10- to 15-percent drop in metabolic efficiency, cooling efficiency, muscle function and overall performance.
Determining sweat rate
Any athlete preparing themselves for peak performance should be on top of their fluid game -- they need to know their individual sweat rate and consequent fluid and electrolyte replacement needs. To determine sweat rate, weigh yourself both immediately pre- and post-exercise on several different occasions making note of environmental conditions and the intensity of the workout.
Every pound of body weight lost during exercise is equivalent to approximately 16 ounces of fluid. For example, if you consistently lose one pound on a 30-minute run in which no fluids are consumed, hourly fluid needs equal 32 ounces per hour, which is actually the upper end of norm for most athletes.
Since 1988, Gatorade Sports Science Institute (GSSI) Laboratories in Barrington, Illinois, have been helping athletes determine sweat rate, providing valuable scientific research and education in the areas of exercise, sports science and nutrition.
In August 2004, I had the opportunity to visit the GSSI lab to undergo a sweat test, which entailed measuring fluid loss and sweat electrolyte content during one hour of moderate-intensity exercise in warm conditions in their labs. Prior to starting the test, my weight was taken and recorded. I was asked to set the speed at an intensity that I was able to maintain easily for an hour. I was able to freely consume Propel Fitness Water during the run.
During the test, sweat patches were strategically placed on several areas of my body to help measure the electrolyte composition in my sweat. After an hour of running, I toweled off the sweat and once again took my weight.
Results of my sweat test at GSSI are shown on the table below and compared to pro triathlete Chris Leigh, who also was recently measured at GSSI Labs. With a fluid intake of only eight ounces and a total weight loss of just under two pounds, my calculated sweat rate was measured at 39 ounces per hour, as compared to the 74 ounces per hour lost by Chris.
The sweat patches were taken off and run through a series of lab tests which helped determine the salt concentration in my sweat, which was 172 milligrams per eight ounces, a concentration far below the Chris Leigh, who has a salt concentration of 350 milligrams per eight ounces.
Kim Mueller | Chris Leigh | |
Athlete Description | 28-year-old competitive female age-group triathlete and runner with no history of muscle cramping. | 31-year-old Australian pro triathlete, who is a two-time Ironman Triathlon champion, winning the 2000 Ironman California and the 2004 Ironman Coeur d'Alene. In 1997 during the Hawaiian Ironman, Chris experienced the extremes of dehydration, including vomiting, diarrhea and severe stomach cramps that led him to collapse just 50 meters from the finish. Shortly after, he had surgery to remove one third of his large bowel, as it had died as a result of dehydration (his body stopped supplying oxygen and nutrients to his large bowel so that blood could continue flowing to his heart, lungs and muscles). |
Exercise Protocol | 1 hr treadmill running at 9.1 mph in a chamber with a constant 76 F temperature and 70% humidity. | 4 hrs of stationary cycling and treadmill running in 88 F and 71% humidity. |
Total Fluid Loss | 1.15 liters | 8.8 liters |
Hourly Fluid Needs | 39 fluid ounces | 74 fluid ounces |
Total Salt Loss | 840 mg | 12,953 mg |
Hourly Salt Needs | 840 mg | 3,238 mg |
Take-home message
To ensure optimal absorption of calories, peak muscle function and efficient cooling of the body, it's essential that athletes stay on top of their fluid game. Determination of sweat rate, which can be calculated by evaluating total fluid intake and weight loss during activity, should be a high priority for athletes looking to maximize performance and protect against serious injury and/or health consequences such as heat stroke.
Electrolytes need to be added to fluids when training in heat and/or training duration extends beyond an hour. Most athletes require .5 to 1 liter of fluid per hour along with .5 to 1 gram of sodium during prolonged training to prevent the detriments associated with fluid and/or electrolyte imbalances.
Kimberly J. Mueller, M.S., R.D., is a registered sports dietitian and competitive endurance athlete who provides nutritional counseling and meal planning to athletes worldwide. For more information about Kim, visit www.kbnutrition.com or contact her at kim@kbnutrition.com.
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