Sports Nutrition Guide Section Links
» Section 1:
An Overview Of Sports Nutrition
» Section 2: Protein & Amino Acids, mTOR, & Protein Synergy
» Section 3: Carbohydrates
» Section 4: Lipids
» Section 5: Understanding Specialty Sports Supplements
» Section 6: Sports Nutrition Guidelines (With Links to Specific Sports)
» Section 7: Special Concerns For Athletic Females
» Section 8: Conclusion
» Section 9: Glossary
» Section 10: References & Suggested Readings
Sports Nutrition Guide Online
Section 6: Sports Nutrition Guidelines (With Links To Specific Sports)
By now, you understand that when you participate in athletic training and competition, your body requires a specialized nutrition and supplement program for maximum performance. Remember, however, that perfecting the skill of a good sports nutrition program takes time and effort.
You should also include the supervision of a health-care professional who can help you fine-tune your diet to meet your specific sports performance needs.
Some useful resources and articles at Bodybuilding.com are found on the database resource page, including:
Note that the sports-specific guidelines are intended for healthy individuals during the pre-competition and competition seasons. Your off-season nutrition requirements will vary with your amount of physical activity and developmental training goals.
The guidelines are intended to present a model to work with and modify if needed to best suit your individuality. As such, there is some flexibility in the percentages of macronutrient intake guidelines, keeping in mind that individuals may have special nutritional needs. The guidelines are a gold standard starting point for advanced, adult, elite athletes.
Also realize that most food content and calorie calculations can range plus or minus 10%, and typically range up to 20% plus or minus. So, while sports nutrition scientists strive to be exact in calculations and recommendations, realistically the food supply and food products content calculations are less exact.
So, do the best you can to achieve the nutrient intake goals, but realize that realistically these are average intake goals, and getting each day's intake to match exactly day after day might not be always be achievable.
To assist you in your sports nutrition quest, I am working on publishing additional guides, which include comprehensive sports nutrition examples, which will be available in eBook formats and online at Bodybuilding.com and Athletes.com.
As water and oxygen are two of the most important nutrients for health and performance, it is appropriate to include general information about this for all athletes. Studies have verified that even minute fluctuations in the body's water balance can and often do, adversely affect performance.
Similarly, the availability of oxygen is vital for top performance, and new research has determined that oxygen utilization can be maximized by physical and nutritional means. In spite of this, many people take water and oxygen for granted or neglect them. This is equally true for athletes and nonathletes.
Q & A
[ Q ] What guidelines do you have regarding water intake?
A: As the body consists of mostly water, adequate water/fluid intake is vital to health and athletic performance. While every person has slightly different water intake requirements, the following will provide and overview of hydration and general guidelines for you to consider.
Water is technically referred to as H
2O, and consists of two hydrogen atoms for every one oxygen atom. It is the aqueous medium used for transporting the body's food materials, and the place where the body's biochemical reactions occur.
Water is found throughout the body, and depending on an individual's body fat, the body can vary in water content, from about 45 percent in very obese individuals to 70 percent in very lean individuals. The different parts of the body also vary in water content.
For example, blood normally has the highest water content, at about 83 percent; muscle tissue has a water content of about 75 percent; bone is about 22 percent water; and fat tissue is only about 10 percent water.
A body's degree of hydration is affected by the person's rate of water intake in relationship to his or her rate of water loss. Water loss is less under resting conditions than under conditions of high-intensity exercising.
Water is obtained from fluids that are ingested as liquids, from fluids that are present in more solid foods, and as a result of metabolic activity within the body. It is estimated that the average-sized man, weighing about 170 pounds and performing moderate nonathletic activities, requires about 80 ounces of water per day to match his water loss.
[ Q ] What are the major sources of water for the human body?
A: The major sources are liquids, foods, metabolic water and glycogen-bound water. The following will provide an overview of each of these major sources.
Liquids are by far the most abundant source of water for the body, accounting for about two-thirds of a person's water intake per day. Liquids can be readily taken in by the body without much digestive effort. Pure water is taken in the fastest.
As the carbohydrate and electrolyte contents of a liquid increase, the length of time that it takes the liquid to empty from the stomach increases. The exact concentration of carbohydrates and electrolytes that an athlete needs depends upon the sport and the level of physical activity.
Meat cooked rare is about 75 percent water, while meat cooked well done is about 45 percent or less water. Ready-to-serve cereals are about 3-to-5 percent water. Generally, approximately one-third of daily water intake is from food.
Metabolic water is the water that is produced in the body as a result of energy production. Often overlooked, it totals approximately 10 ounces per day, depending on how many calories are burned.
Metabolic water is produced from oxygen and hydrogen atoms. The oxygen atoms are obtained from the atmosphere and brought into the body via the lungs during breathing. The hydrogen atoms are obtained from carbohydrates, fatty acids, and other carbon molecules that are broken down in the body for energy.
Glycogen-bound water is stored in the muscles along with glycogen. About 3 ounces of water are stored along with every 1 ounce of glycogen.
| What Is Glycogen?
Glycogen is the principal stored form of carbohydrate energy (glucose), which is reserved in muscles. When your muscles are full of glycogen, they look and feel full.
Glycogen-bound water becomes important when the glycogen supply is in the process of being depleted for energy use. This occurs during training and endurance events lasting more than one hour and during periods of calorie restriction.
During intensive endurance activities, about 16 fluid ounces of water may be released per hour. However, this water will be released only for as long as the glycogen to which it is bound remains stored in the body.
Glycogen-bound water must be replenished when it is used. Altogether, approximately 3-to-4 pints of glycogen-bound water can be stored. For endurance athletes and athletes performing in day-long tournaments, glycogen-bound water is an important source of hydration during physical activity. It can be maximized through carbohydrate loading.
[ Q ] What are the major ways that water is lost by the body?
A: The major ways that the body loses water are from urination, defecation, sweating, and breathing. In addition, the rate of water loss varies with the size of the individual, the duration and intensity of the activity and the weather.
Water loss is affected by factors such as the weather, the ability to acclimate to the temperature, the duration and intensity of the activity, the rate of sweating, the weight of the clothing worn, health, gastrointestinal problems, alcohol and caffeine consumption, the use of diuretics and other medications and body fat.
The following provides an overview of the 4 primary methods of water loss in the human body.
Urination is the process by which water is filtered out through the kidneys and excreted as urine. Urine output under normal circumstances is roughly 1½ to 2 quarts per day.
Interestingly enough, water loss from the kidneys is minimized during exercise. During exercise, fluid loss from the kidneys is slowed down to only ounces per hour. This is due to certain hormones, in particular Antidiuretic Hormone (ADH) (also known as vasopressin). The ADH level increases during exercise, which increases the amount of water that is reabsorbed by the kidneys, thereby decreasing water loss.
Note that alcohol (ethyl alcohol) and caffeine have diuretic effects because they inhibit ADH and therefore increase water output from the kidneys. Alcoholic and caffeinated beverages should be avoided during the season and especially during the last seven days prior to a major athletic event.
| What Does Diuretic Mean?
Increasing the amount of water in the urine, removing excess water from the body; increasing the flow of urine from the body.
Food intake can also affect the rate of water loss from the kidneys. It takes about 16 fluid ounces of water to remove 1 ounce of solids from the bloodstream through the kidneys.
Therefore, foods that leave higher amounts of waste products, such as protein, can speed up the body's dehydration process and should be minimized twenty-four hours before major competitions in sports where dehydration is a concern.
Under normal conditions, water loss through defecation is relatively small, about 4 to 8 ounces per day.
However, a person with gastrointestinal upset, such as diarrhea or vomiting, can lose 32 to 160 fluid ounces of water in a day. It is therefore important for athletes with gastrointestinal problems to consume more than the normal amount of liquid to compensate for this extra water loss.
Water is lost through the skin when the body sweats. The body always sweats to some degree, but sweating becomes evident when conditions such as humidity or increased activity cause water to accumulate on the skin. Sweating is the body's cooling mechanism.
Sweating removes excess heat to keep the body's core temperature within a limited range and to prevent the body from overheating. If a body overheats from dehydration, the possible results include heat stroke, fainting and even death.
Sweat must evaporate from the skin to have a cooling effect. The production of sweat is just the first step in the process. Sweating is a major mode of water loss during exercise. Over 1 quart of water can be lost per hour via sweating during prolonged exercise, such as long-distance running.
A small amount of water is lost during the process of breathing in the form of water droplets in the air that is exhaled. These water droplets amount to about 10 to 12 fluid ounces per day. This amount is increased during exercise, since breathing is accelerated.
[ Q ] What are the effects of dehydration on performance?
A: Dehydration can, and does, affect athletic performance. As the body loses water, its core temperature rises. This affects all the metabolic pathways, interferes with
cardiovascular functioning, and reduces total exercise capacity.
When the water losses reach 1-to-4 percent of the body weight, athletic performance is reduced. During a race, marathon runners can lose several quarts of water, representing 6-to-10 percent of their body weight.
If they do not properly rehydrate during the race, they will find that this amount of water loss can significantly impair their performance and possibly even put their well-being at risk. Non-endurance sports such as football, basketball, hockey and soccer can cause similar water losses.
During tournaments, no matter what the sport is, athletes must make sure they increase their water intake to compensate for the prolonged exercise over the one or two days of competition.
Sports in which participants must meet weight-class requirements - boxing and wrestling, for example - are also associated with dehydration. Wrestlers typically dehydrate themselves to make a lower weight class. This type of chronic dehydration decreases performance and adversely affects health.
Chronic dehydration will develop in any athlete who does not make an effort to remain adequately hydrated. The thirst response in humans is not as finely tuned as it should be.
This means that the body can enter a state of dehydration and the person may not feel the sensation of thirst for several hours. Therefore, you should not rely solely on your thirst response but should, instead, make a point to keep rehydrating your body all day long.
[ Q ] What are the special water needs of the athlete?
A: The amount of water you need varies greatly according to your initial level of hydration, the climate, and the duration and
intensity of your activity. As a general rule, measure your water intake by your water loss - namely, your frequency of urination. If you are well-hydrated, you should be urinating several or more times a day.
If you urinate only a few times per day, you probably need to increase your water intake. Because thirst is not a good indicator of hydration level, you should get in the habit of drinking water or other fluids frequently through the day.
Daily hydration guidelines are important for all athletes to follow. Studies have shown that endurance athletes who compete for periods longer than 30 minutes improve their performance by drinking fluids during the activity.
|BASELINE WATER INTAKE CALCULATOR|
Athletes competing in shorter events need to be properly hydrated from the start to achieve peak performance. But, you should also be aware that over-hydration is not healthy either, and may impair performance. So you need to do some experimenting of your own to determine your optimum hydration requirements for maximum performance.
[ Q ] What would be some general daily hydration guidelines for athletes?
A: Daily hydration is vital for everyone - endurance athletes, power athletes, and even nonathletes. Table 6.1 presents general water-intake guidelines for healthy, active individuals who exercise on a regular basis.
Researchers have found that the best way to determine the recommended daily water intake is to look at daily energy expenditure. Table 6.1 provides a minimum daily water-intake range to accommodate individual differences as well as climatic differences. As the temperature climbs above 70 degrees Fahrenheit (F) [21.1 degrees Celsius] and the humidity above 70 percent, water loss will be increased due to increased sweating, especially during exercise.
|Table 6.1. Daily Hydration Guideline Estimates.|
Attaining and maintaining a peak hydration level starts by following the daily hydration guidelines discussed above. For athletes competing in endurance events lasting more than 30 minutes, hydration supercompensation (water loading) before an event as well as hydration maintenance during the event have been shown to increase athletic performance. (For a description of hydration super compensation, see "Pre-Event," below.)
Other athletes should make sure that they properly maintain their hydration levels leading up to the event, but they do not necessarily need to concern themselves with drinking water during their events. One exception is athletes competing in tournaments that require participation in several events per day or several events over several days.
Specific guidelines for optimum athletic performance to be observed every day plus before, during and after athletic events are as follows: Every day. During your athletic season, keep track of your water intake on a daily basis. In addition, weigh yourself in the morning and after practice to keep track of your daily body-weight fluctuations.
In general, the human body does not lose much fat per day, so if you find yourself losing several pounds of body weight on a particular day, it is from water loss.
Whether you are participating in an endurance or nonendurance event, you should load up on water about two hours before your competition.
Depending on your bodyweight, you should consume between 18 and 24 ounces of water. This will allow you to "top off" your body with water and still give yourself enough time to urinate the excess before your event.
Fifteen to twenty minutes before your event, drink another 12-to-20 ounces of water. Do not drink any alcohol, coffee or other beverages that tend to act as diuretics. Also avoid taking any dehydrating medications.
During The Event
Remember that the main reason for drinking water during endurance events is to replace sweat. Sweating is essential for cooling the body. If your body temperature increases too much during your event, your performance will suffer. To prevent this, you need to encourage sweating and make sure that the sweat evaporates from your body.
Take special care on hot, humid days, which are the worst for athletic activities because they cause the most sweating with the least amount of evaporation.
Ideally, during your event, drink 6-to-9 ounces of cool water every 15-to-20 minutes.
Give your body a chance to cool down and your heartrate a chance to normalize, then start drinking water or a sports rehydration drink.
Please note that if you follow these hydration guidelines during events, you should also follow them during practice, as practice for most sports lasts longer then the competition events. This way, your body will have a chance to adjust to ingesting the recommended amounts of water before the day of competition.
[ Q ] How is oxygen important to athletic performance?
A: Oxygen, like water, is something that most people do not consider a nutrient but that the body cannot survive without. Oxygen is needed in every cell of the body for the production of energy and other biochemical reactions. Knowing the dynamics of oxygen uptake and utilization can help you plan a scientific and sound performance-enhancement program.
The best training program not only builds muscles and increases stamina but also improves the body's ability to take in and properly utilize oxygen, which builds bigger muscles and increases stamina even further.
Oxygen takes a circuitous route through the body, first by entering the lungs, and then travels via the bloodstream through the heart to the cells of the muscles, brain and other tissues. The lungs are also the last stop for the waste products of oxygen metabolism, which are carried away from the cells through the blood vessels and eventually exhaled into the air.
The lungs are the first step in the operation that brings oxygen into the body system. The lungs are a pair of organs that sit in the chest on either side of the heart. They process the air that is breathed in, removing the oxygen and transferring it to the bloodstream for distribution throughout the body.
The amount of air that the lungs can process varies with the condition of the person - a conditioned person can process more air than a deconditioned person can. The amount of air that the lungs can process is therefore a limiting factor.
The lungs have no muscles of their own. To expand and contract, they must depend completely upon the muscles of the rib cage and diaphragm. Upon inhalation, the muscles surrounding the lungs increase the available space within the lung cavity. When they do this, they cause a partial vacuum, which helps to suck air into the lungs.
Upon exhalation, assisted somewhat by the natural elasticity of the lungs and the chest wall, the muscles contract to create greater atmospheric pressure inside the lungs than outside the body. This causes the air to be pushed out.
| The Lungs
The lungs of mammals have a spongy texture and are honeycombed with epithelium having a much larger surface area in total than the outer surface area of the lung itself. The lungs of humans are typical of this type of lung.
Breathing is largely driven by the diaphragm below, a muscle that by contracting expands the cavity in which the lung is enclosed. The rib cage itself is also able to expand and contract to some degree.
When the body is in action, however, the amount of air that the lungs can inhale and exhale becomes limited by the size of the vacuum the muscles can create for the lungs to expand into and the size of the area the lungs can squeeze back down into.
A conditioned person in action obviously has the capability to inhale more air and for longer periods of time than an unconditioned person has. A conditioned person is also capable of exhaling more waste products because the muscles around the lungs have been trained to do more work.
During the metabolism of energy substrates, such as fats, carbohydrates, and some amino acids, a complex series of biochemical steps, leads to the production of ATP for energy. During this production of energy from the macronutrients, a molecule of oxygen is needed in the final step.
| What Is ATP?
Otherwise known as Adenosine TriPhosphate, ATP is critical to the release of energy. ATP is an adenosine-derived nucleotide that supplies large amounts of energy to cells for various biochemical processes, including muscle contraction and sugar metabolism, through its hydrolysis to ADP.
Oxygen therefore draws oxidative energy production along these complex biochemical pathways. Optimum oxygen intake and distribution through the body is vital for maximum performance and good health.
Development of good breathing technique is an important part of maximizing the oxygen intake capacity of your lungs. As the diaphragm contracts, it moves down in to the abdominal cavity and the stomach expands like a bellows.
Developing this good deep breathing technique from the abdomen will lead to maximum lung utilization. If you find that you are breathing from your chest, this will reduce your lung capacity and reduce physical performance. Take note of this, and make an effort to develop good breathing technique.
[ Q ] How do I find the Sports Specific Nutrition and Supplement Guidelines?
A: Click on the sport specific link below, which will take you to the Sports Specific Nutrition page. The Sports Specific Nutrition pages are linked to Sport Specific Supplement pages, for guidelines about which sports supplements you should consider using.
For More Information
You can subscribe to my Awesome Muscles Podcast Series to hear about the latest and greatest information about training and nutrition for sports, fitness and health. This is an online podcast seminar series, which you can also listen to online or download on to your computer and/or iPod (mp3 player).
| What Is A Podcast?
Podcasting is a collection of technologies for automatically distributing audio and video programs over the Internet via a publish and subscribe model.
Podcasting enables independent producers to create self-published, syndicated "radio shows," and gives broadcast radio or television programs a new distribution method.
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Notice and Disclaimer: This sports nutrition guide and related articles and seminar series are not intended for use as a substitute for consultation with a qualified medical practitioner. If you have symptoms of any illness or injury, it is essential that you see your doctor immediately for proper treatment.
This information is for education and entertainment purposes only. We strongly recommend that you consult a physician before beginning any exercise program and nutrition program. You should understand that participating in any exercise program can result in physical injury and you agree to do so at your risk.