Nutrition

SPORTS NUTRITION - ARE YOU FUELING YOUR BODY CORRECTLY?

Athletes who want a winning edge need the right nutrition. When you give your body the right fuel by drinking enough water and eating a balanced diet, you will make the most of your athletic talents and gain more strength, power, and endurance when you train.

This article contains some general sports nutrition guidelines. To achieve top performance, your diet should be based on a variety of factors including your age, weight, physical condition, and the type of exercise you are doing. Consult your doctor for individualized sports nutrition advice.

Here at Champion Performance and Physical Therapy, we have staff members who have first-hand experience in sports nutrition and what it takes to transform your body at a competitive level, and at a level purely for health purposes.  Call us today at 913-291-2290 to hear more about our nutrition coach, Kaitlin. 

Hydration

Water is the most important nutrient for athletes. Water comprises about 60% of body weight and is essential for almost every bodily function. Because your body cannot make or store water, you must replace the water that you lose in your urine and sweat.

Everyone should drink at least two quarts (64 oz.) of water each day—and athletes need even more. To stay hydrated and avoid overheating, drink plenty of fluids before, during, and after sports or exercise. When you work out or compete, especially in hot weather, try to replace the amount of water you lose in sweat by drinking the same amount of fluid.

Stay hydrated by drinking plenty of fluids before, during, and after exercise.

Drinking cool water is the best way to keep hydrated during workouts or events that last an hour or less. Sports drinks made up of 6% to 10% carbohydrates can help you stay hydrated during longer events. Most sports drinks should be diluted with approximately 50% water.

Because thirst is not a reliable way to tell if you need water, be sure to drink even if you are not thirsty. You will not start feeling thirsty until you have already lost about 2% of your body weight—enough to hurt performance. Also, if you stop drinking water as soon as your thirst is satisfied you will get only about half the amount you really need.

The following tips will help you stay hydrated:

  • Drink small amounts of water frequently rather than large amounts less often.
  • Drink cool beverages to lower your core body temperature and reduce sweating.
  • Track your sweat loss by weighing yourself both before and after exercise. For every pound lost through sweat, drink 16 to 24 oz. of water. Your body weight should be back to normal before your next workout.
  • Pay attention to the amount and color of your urine. A large volume of clear urine is a sign that you are well-hydrated. Smaller amounts or dark yellow urine can indicate dehydration.

Fuel Sources

A balanced diet is another key to sports nutrition. Eating the right combination of fuel (calories) from carbohydrates, proteins, and fats will give you energy for top performance.

Carbohydrates

Carbohydrates—the most important source of fuel—should provide about 60% to 70% of your daily calories. Carbohydrates are found in many foods, including:

  • Fruits
  • Vegetables
  • Pasta
  • Bread
  • Cereal
  • Rice

Eating fruit, or another food high in carbohydrates, will help you maintain energy during competition.

Your body converts the sugars and starches in carbohydrates into energy (glucose) or stores it in your liver and muscle tissues (glycogen). This gives you endurance and power for high-intensity, short-duration activities.

If your body runs out of carbohydrate fuel during exercise it will burn fat and protein for energy—causing your performance level to drop. This may happen if you start exercising without enough stored muscle glycogen or if you exercise intensely for longer than an hour without eating more carbohydrates. It may also happen if you do multiple repetitions of high-intensity, short-duration exercises or if you participate in multiple events or training sessions in a single day.

The following tips will help you maintain carbohydrate fuel so that you can stay energized and perform at your best:

  • Start your exercise or competition with glycogen-loaded muscles by eating carbohydrates for at least several days before the event.
  • To replenish energy and delay fatigue, eat additional carbohydrates when you exercise or compete for longer than one hour.

Proteins

Proteins should provide about 12% to 15% of your daily calories. Proteins are found in many foods, including:

  • Meat
  • Fish
  • Poultry
  • Eggs
  • Beans
  • Nuts
  • Dairy products

Proteins give your body the power to build new tissues and fluids among other functions. Your body cannot store extra protein so it burns it for energy or converts it to fat. The amount of protein you need depends, in part, on your:

Good sources of protein include meat, cheese, eggs, and nuts

  • Level of fitness. Physically active people need more protein than those who do not exercise. You also need more protein when you start an exercise program.
  • Exercise type, intensity, and duration.Endurance athletes often burn protein for fuel, as do bodybuilders and other athletes who perform intense strength-building activities.
  • Total daily calories. Your body burns more protein if you do not consume enough calories to maintain your body weight. This can happen if you eat too little or exercise too much.
  • Carbohydrate intake. Your body may use protein for energy if you exercise with low levels of muscle glycogen or if you do repeated training sessions without eating more carbohydrates. When you start with enough muscle glycogen, protein supplies about 5% of your energy; otherwise, it may supply up to 10%.

Fats

Fats should provide no more than 20% to 30% of your daily calories. Saturated fats come from animal-based foods, such as meats, eggs, milk, and cheese. Unsaturated fats are found in vegetable products such as corn oil.

Your body needs small amounts of fat for certain critical functions and as an alternative energy source to glucose. Eating too much fat, however, is associated with heart disease, some cancers, and other major health problems. Also, if you are eating too much fat, it probably means that you are not eating enough carbohydrates.

How your body uses fat for energy depends on the intensity and duration of exercise. For example, when you rest or exercise at low to moderate intensity, fat is the primary fuel source. As you increase the intensity of your exercise your body uses more carbohydrates for fuel. If your body uses up its glycogen supply and you continue exercising you will burn fat for energy, decreasing the intensity of your exercise.

Nutrition Before Competition

What you eat several days before an endurance activity affects performance. The food you eat on the morning of a sports competition can ward off hunger, keep blood sugar levels adequate, and aid hydration. Try to avoid eating high-protein or high-fat foods on the day of an event since this can put stress on your kidneys and take a long time to digest.

To perform at your highest level, follow these general nutrition guidelines before an event:

  • Eat a meal high in carbohydrates.
  • Eat solid foods 3 to 4 hours before an event. Drink liquids 2 to 3 hours before an event.
  • Choose easily digestible foods, rather than fried or high-fat foods.
  • Avoid sugary foods and drinks within one hour of the event.
  • Drink enough fluids to ensure hydration. A good guideline to follow is: Drink 20 oz. of water 1 to 2 hours before exercise and an additional 10 to 15 oz. within 15 to 30 minutes of the event. Replenishing fluids lost to sweat is the primary concern during an athletic event. Drink 3 to 6 ounces of water or diluted sports drink every 10 to 20 minutes throughout competition.

    Nutrition will vary depending upon the type of exercise you engage in, and the level of performance.  High level or performing at a competitive level will require a different kind of nutrition, as will many of the less common exercises, such as powerlifting, CrossFit training, and body building. 

Carbohydrate Loading

To avoid running out of carbohydrates for energy, some endurance athletes—including long-distance runners, swimmers, and bicyclists—load their muscles with glycogen. To do this they eat extra carbohydrates and exercise to energy depletion several days before an event. To "carbohydrate load" before an event:

  • First, exercise to muscle fatigue. Your workout must be identical to the upcoming event to deplete the right muscles.
  • Next, eat a high-carbohydrate diet (70% to 80% carbohydrates, 10% to 15% protein, and 10% to15% fat), and do little or no exercise for three days before the event.

Some endurance athletes believe that following this carbohydrate-loading regimen will ensure that muscles loaded with unused glycogen will be available to work for longer periods of time during competition. Consult your doctor for advice before trying a carbohydrate-loading diet.

CALCIUM, NUTRITION, & BONE HEALTH

The health and strength of our bones rely on a balanced diet and a steady stream of nutrients, most importantly, calcium and Vitamin D.

Calcium is a mineral that people need to build and maintain strong bones and teeth. It is also very important for other physical functions, such as muscle control and blood circulation.

Calcium is not made in the body — it must be absorbed from the foods we eat. To effectively absorb calcium from food, our bodies need Vitamin D.

If we do not have enough calcium in our diets to keep our bodies functioning, calcium is removed from where it is stored in our bones. Over time, this causes our bones to grow weaker and may lead to osteoporosis — a disorder in which bones become very fragile.

Postmenopausal women are most vulnerable to osteoporosis. Although loss of estrogen is the primary reason for this, poor lifelong calcium and Vitamin D intake, as well as lack of exercise, play a role in the development of osteoporosis.

Note that men also are at risk for osteoporosis — typically later in life than women — and it is important for them to keep track of calcium intakes, as well.

Calcium

Calcium needs vary with age. The Food and Nutrition Board (FNB) of the Institute of Medicine of the National Academies provides guidelines on the amount of calcium needed each day.

Recommended Daily Allowance in Milligrams (mg)

Women and Men 9 to 18 years: 1,300 mg
Women and Men 19 to 50 years: 1,000 mg
Women 51 to 70 years: 1,200 mg
Men 51 to 70 years: 1,000 mg
Women and men > 70 years: 1,200 mg
Pregnant or nursing women 14 to 18 years: 1,300 mg
Pregnant or nursing women 19 to 50 years: 1,000 mg

Reprinted and adapted with permission from Tables S-1 and S-2, Dietary Reference Intakes for Calcium and Vitamin D, 2011 by the National Academy of Sciences, Courtesy of the National Academies Press, Washington, D.C.

Dietary Sources of Calcium

People can get the recommended daily amount of calcium by eating a healthy diet that includes a variety of calcium-rich foods. Milk, yogurt, cheese, and other dairy products are the biggest food sources of calcium. Other high-calcium foods include:

  • Kale, broccoli, Chinese cabbage (bok choy) and other green leafy vegetables
  • Sardines, salmon, and other soft-bone fish
  • Tofu
  • Breads, pastas and grains
  • Calcium-fortified cereals, juices, and other beverages.

Good sources of calcium include milk, cheeses, leafy green vegetables, and almonds.

A more complete listing of calcium-rich foods is included at the end of this article.

Some foods make it harder for the body to absorb calcium. In particular, sodas and carbonated beverages should be avoided, not just for bone health but for many nutritional reasons, including preventing obesity. Sodas decrease calcium absorption in the intestines and contain empty calories. Milk, calcium-fortified juices, and water are better beverage alternatives for all age groups.

Calcium Supplements

Although adequate calcium can be obtained through your diet, it is difficult for many people, particularly for those who avoid dairy products. People who are lactose-intolerant or vegetarians who do not eat dairy products have a harder time getting enough calcium from foods.

It is also hard to get enough calcium from the diet during certain times of our lives, such as in adolescence when our bodies require more calcium to build strong bones for life. Postmenopausal women and men older than age 70 also require more calcium to slow down bone loss.

Doctors recommend calcium supplements to those who do not get enough calcium from the foods they eat. Although calcium is sometimes found in multivitamins, it is typically not in significant amounts. Many people need to take separate calcium supplements to ensure they reach the Recommended Dietary Allowance for their life stage.

Not all the calcium consumed — whether through food or supplement — is actually absorbed in the intestines. Research shows that calcium is absorbed most efficiently when it is taken in doses less than 500 mg. Because many calcium supplements come in 500 mg doses, people who require 1,000 mg of supplementation each day should take their doses at separate times. Newer daily slow release formulations of calcium citrate that supply 1200 mg have recently become available.

Most calcium supplements also contain Vitamin D, which helps the body absorb calcium.

Vitamin D

Without Vitamin D, our bodies cannot effectively absorb calcium, which is essential to good bone health.

Children who lack Vitamin D develop the condition called rickets, which causes bone weakness, bowed legs, and other skeletal deformities, such as stooped posture. Adults with very low Vitamin D can develop a condition called osteomalacia (soft bone). Like rickets, osteomalacia can also cause bone pain and deformities of long bones.

Vitamin D Recommended Dietary Allowance

The FNB recommends 400 International Units (IU) of Vitamin D for infants during the first year of life. The RDA for everyone from age 1 through 70 years is 600 IU. Recent research, however, supports that the body needs at least 1000 IU per day for good bone health, starting at age 5 years.

Many foods contain some Vitamin D, however, few contain enough to meet the daily recommended levels for optimal bone health.

The American Academy of Pediatrics recommends that all children take Vitamin D supplements.

In the 19th and early 20th centuries, children were routinely given cod liver oil for a range of medicinal purposes. When cod liver oil was tied to the prevention and treatment of rickets, Vitamin D was discovered. Soon after, Vitamin D was added to milk — one glass of milk contains about 100 IU of Vitamin D. As a result, parents stopped using cod liver oil. Because today's children do not drink as much milk as in the past, it is difficult for them to get enough Vitamin D from milk. In addition, other dairy products are not typically supplemented with Vitamin D. Getting enough Vitamin D from what we eat is very difficult.

Although our bodies can make Vitamin D in our skin when it is exposed to good sunlight, it is very important to protect our skin by using sunscreen when we are outdoors. This blocks the excessive UV radiation that can cause skin cancer. Sunscreen does, however, also block our skin's ability to make Vitamin D. This is why doctors often recommend Vitamin D supplements for both adults and children. The American Academy of Pediatrics recommends that all children — from infancy through adolescence — take Vitamin D supplements.

Safe Levels of Calcium and Vitamin D

Too much calcium and/or Vitamin D can be harmful and cause serious side effects. In addition to establishing RDA guidelines, the FNB has established Tolerable Upper Intake Levels (ULs). These represent the highest levels of calcium and Vitamin D that can be consumed by the average individual and still be safe.

These ULs are important guidelines for people who may require different dosages of these supplements. For example, people who live in areas with little sun, those with darker skin, and people who are obese may need more Vitamin D than the recommended daily amount.

Note that ULs are not levels that people should try to reach — they are the safe limits based on current research. When intake goes beyond the ULs listed below, the risk for serious side effects increases.

Upper Safe Limit for Calcium Intake

Life Stage: Upper Safe Limit

Birth to 6 months: 1,000 mg
Infants 7-12 months: 1,500 mg
Children 1-8 years: 2,500 mg
Children 9-18 years: 3,000 mg
Adults 19-50 years: 2,500 mg
Adults 51 years and older: 2,000 mg
Pregnant and breastfeeding teens: 3,000 mg
Pregnant and breastfeeding adults: 2,500 mg

Upper Safe Limit for Vitamin D Intake

0-6 months: 1,000 IU1,000 IU  
7-12 months: 1,500 IU1,500 IU  
1-3 years: 2,500 IU2,500 IU  
4-8 years: 3,000 IU3,000 IU  
≥9 years: 4,000 IU4,000 IU4,000 IU4,000 IU

Reprinted and adapted with permission from Tables S-1 and S-2, Dietary Reference Intakes for Calcium and Vitamin D, 2011 by the National Academy of Sciences, Courtesy of the National Academies Press, Washington, D.C.

More foods in the U.S. are being fortified with calcium and Vitamin D, and awareness of the importance of these nutrients for bone health is growing. In recent years, the media has reported on the potential health benefits of taking high levels of Vitamin D, such as in the areas of cancer prevention, diabetes management, and heart health. As a result, it is becoming more likely that people may consume unsafe quantities of these nutrients.

The FNB conducted an extensive review of the medical literature and found enough evidence of bone health benefits to support raising the UL levels on Vitamin D in adults from 2000 IU to 4000 IU. What was also determined, however, is that very high levels of Vitamin D (above 10,000 IUs per day) can cause kidney damage and dangerously high serum calcium levels. Too much calcium from dietary supplements can also cause adverse health effects, including kidney stones, higher risks for heart problems, and possibly increased risk for prostate cancer.

Calcium and Vitamin D are essential for good bone health, but must be consumed safely. If you are not sure what intake levels are right for you and your health needs, be sure to talk to your doctor.

Other Key Nutrients in Bone Health

Many other nutrients — most found naturally and at sufficient levels in a typical diet — contribute to bone health and growth. They include:

  • Phosphorus. A major mineral in the body's bone crystal, phosphorus is found in dairy products and meat. Vitamin D improves phosphorus absorption in the intestine and kidney.
  • Magnesium. Primarily found in bone crystals, magnesium improves bone strength. Older adults are more likely to be deficient in magnesium. Calcium supplements that contain magnesium can help.
  • Vitamin K. Necessary for bone formation and mineralization, Vitamin K also is important for blood clotting, and may assist in channeling calcium directly to the bone rather than the blood vessels.
  • Vitamin C. Collagen is the main protein in bone, and Vitamin C is necessary for collagen synthesis. Vitamin C is present in citrus fruits and tomatoes and in many vegetables.
  • Vitamin A. Vitamin A is necessary for cells to differentiate normally and for normal skeletal growth, and also is extremely important for eye health. Vitamin A is available in liver, eggs, butter, green leafy vegetables and carrots. Too little vitamin A is a major cause of blindness worldwide. In contrast, too much vitamin A can cause bone loss and increase the risk of hip fracture. The animal source supplements (retinols) may cause toxicity but plant sources (B carotene) do not. Daily intake of retinols should be less than 10,000 IU.

Dietary Sources of Calcium

Selecting foods high in calcium is one way to help you achieve your targeted daily calcium intake. Here are some major food sources of calcium to assist your meal planning.

Selected Food Sources of Calcium

FoodMilligrams (mg) per servingPercent DV*
Yogurt, plain, low fat, 8 ounces
Orange juice, calcium-fortified, 6 ounces
Yogurt, fruit, low fat, 8 ounces
Mozzarella, part skim, 1.5 ounces
Sardines, canned in oil, with bones, 3 ounces
Cheddar cheese, 1.5 ounces
Milk, nonfat, 8 ounces
Milk, reduced-fat (2% milk fat), 8 ounces
Milk, buttermilk, 8 ounces
Milk, whole (3.25% milk fat), 8 ounces
Tofu, firm, made with calcium sulfate, 1/2 cup***
Salmon, pink, canned, solids with bone, 3 ounces
Cottage cheese, 1% milk fat, 1 cup
Tofu, soft, made with calcium sulfate, 1/2 cup
Instant breakfast drink, various flavors and brands, powder prepared with water, 8 ounces
Frozen yogurt, vanilla, soft serve, 1/2 cup
Ready-to-eat cereal, calcium-fortified, 1 cup
Turnip greens, fresh, boiled, 1/2 cup
Kale, fresh, cooked, 1 cup
Kale, raw, chopped, 1 cup
Ice cream, vanilla, 1/2 cup
Soy beverage, calcium-fortified, 8 ounces
Chinese cabbage (bok choy) raw, shredded, 1 cup
Bread, white, 1 slice
Pudding, chocolate, ready to eat, refrigerated, 4 ounces
Tortilla, corn, ready-to-bake/fry, one 6" diameter
Tortilla, flour, ready-to-bake/fry, one 6" diameter
Sour cream, reduced fat, cultured, 2 tablespoons
Bread, whole-wheat, 1 slice
Broccoli, raw, 1/2 cup
Cheese, cream, regular, 1 tablespoon

* DV = Daily Value. DVs were developed by the U.S. Food and Drug Administration to help consumers compare the nutrient contents among products within the context of a total daily diet. The DV for calcium is 1,000 mg for adults and children aged 4 years and older. Foods providing 20% of more of the DV are considered to be high sources of a nutrient, but foods providing lower percentages of the DV also contribute to a healthful diet. The U.S. Department of Agriculture's Nutrient Database Web site lists the nutrient content of many foods. It also provides a comprehensive list of foods containing calcium.

** Calcium content varies slightly by fat content; the more fat, the less calcium the food contains.

*** Calcium content is for tofu that is processed with a calcium salt. Tofu processed with other salts does not provide significant amounts of calcium.

Source: National Institutes of Health (NIH) (Dietary Supplement Fact Sheet: Calcium): U.S. Department of Agriculture, Agricultural Research Service. 2011. USDA National Nutrient Database for Standard Reference, Release 24. Nutrient Data Laboratory Home Page; Institute of Medicine of the National Academies Dietary Reference Intakes for Calcium and Vitamin D.