What You Should Know About Sports Nutrition and Supplements
by Kristen Orquia; Darcy Wruk; Kelly A Erdman

Carbohydrates or protein? Water or Gatorade(TM)? When it comes to sports, questions like these ones are common, as the trend towards healthy living become more popular. We are more aware of the benefits of an active lifestyle. At the same time, we have become overwhelmed with the variety of products, fad diets and media advice. Proper nutrition, fluid replacement and occasional supplements remain key to improving athletic performance.

Nutrition - back to basics

Eating enough carbohydrate, fat, and protein is the most effective way to get the most energy. Carbohydrates provide the most energy storage before and during a workout. Eat both simple and complex carbohydrates, including whole grains, fruits, and vegetables. Carbohydrate should make up about 50 to 55 per cent of a person's total calorie intake. Endurance athletes need slightly more, around 55 to 60 per cent of their total calorie intake.

To maintain an adequate store of energy during a workout, a strict routine for eating these carbohydrates is suggested. They should be eaten one to four hours before and every hour during longer workouts. Eat them again 30 minutes after a workout, followed by every two hours. In this latter stage, replacing carbohydrates is extremely important, especially during the first two hours. This helps restore energy stores (glycogen).

Fats also provide a good source of energy. A low fat diet with only 25 to 30 per cent of total calorie intake coming from fat is advised. This should be combined with a high carbohydrate diet. Unsaturated fats found in vegetable oils, nuts, and seeds are good sources of essential dietary fats.

Proteins build and maintain muscle mass. As well, they are needed to make enzymes, hormones, and antibodies. Foods rich in protein provide key micronutrients, such as iron, zinc, and B vitamins, all essential for good health and fitness.

The recommended protein intake remains controversial. Contrary to some of today's fad diets, a low protein diet in the range of 12 to 15 per cent of calories is safe and effective for athletes.

High protein diets often displace the amount of carbohydrate eaten and can cause dehydration. Both hamper athletic performance. The list of long-term side effects and health concerns are other arguments against loading up on protein. Moderate protein intake throughout the day is all that is needed for the average person. Athletes who strength train need slightly more dietary protein than athletes who do endurance or judged events.

Forgotten fluids

Many recreational athletes commonly experience dehydration. During any workout, water is lost through sweat as a way to reduce body heat. Unfortunately, many athletes neglect to replace their fluid losses. Symptoms of dehydration include infrequent passing of urine, dark colored urine, fatigue, muscle cramps, and stomach upset.

Over 60 per cent of human body weight is made up of water. So, dehydration can also show as a significant weight loss. It is estimated that a loss of one litre of sweat is the same as a one kilogram loss in body weight. While from a weight loss perspective this might appear favorable, it is not. In feet, dehydration interferes with athletic endurance. Any fluid loss has the potential to increase heart and breathing rates. It many even lead to heat exhaustion.

To avoid this problem, a strict fluid replacement schedule is recommended. Two hours before exercising, 500 millilitres of fluid should be consumed. Drink another 150 to 300 millilitres every 15 to 20 minutes during exercise. Finally, after exercise, 750 millilitres should be taken in for every pound of weight lost.

Which type of fluid is best to drink? If you have exercised for less than an hour, water is the best choice to replace fluid lost from sweating. After exercising more than 60 minutes, a glucose electrolyte solution such as Gatorade(TM) or PowerAde(TM) is best. Sports drinks such as these are effective for prolonged exercise. They contain carbohydrate sources (glucose, sucrose or glucose polymers) to provide energy. These drinks also have electrolytes (sodium, chloride or potassium) that allow rapid absorption in the body.

When choosing an appropriate sports drink, check the label for the recommended combination. Ideal carbohydrate sources include glucose, glucose polymers or sucrose. Total carbohydrate concentration should be four to eight percent. The amount of sodium (Na) should be about 500 to 700 milligrams per litre. Read the label on sports drinks carefully. Note that the amount of sodium and potassium is usually for the suggested serving size, not for the entire bottle.

Fruit juices and soft drinks often contain more than ten per cent of carbohydrate concentration. This amount of carbohydrate is poorly absorbed in the stomach. Such drinks can upset your stomach during exercise due to their high fructose content and so are not recommended.

To supplement or not to supplement

It is often suggested that supplements are not necessary for those who eat a well balanced diet and follow the recommended nutrition guidelines. If you are lacking in some areas, a few helpful supplements for athletes include B vitamins, calcium and iron.

B vitamins are found in unrefined complex carbohydrates, meats, eggs, and some fruits and vegetables. These are necessary for the body to use protein and make energy. Calcium is well known to protect bones from osteoporosis (fragile bones) and stress fractures. Adult athletes need 1000 milligrams of elemental calcium per day, while adolescents need 1300 milligrams. Finally, iron carries oxygen to working muscle cells during exercise. Still, too much iron can have differing effects.Analysis of blood and diet by health professionals is recommended before you begin taking diet supplements.

A word on creatine

Several performance-improving aids have appeared in recent years. Since creatine first came out on the market, the 'creatine craze' has not died down. It is still one of the more scientifically studied sport supplements available, as it improves brief, high-intensity exercise.

Each day, the body makes about one gram of creatine naturally. Creatine also comes from animal products such as pork, beef and fish, which can provide another gram per day. The body uses this supply of creatine as a source of energy during exercise and training. Supplements of creatine are thought to improve this energy system. Athletes are able to train harder since energy is restored more quickly.

Several dosage routines have been recommended to get the most muscle storage of creatine. A suggested loading maintenance routine starts with taking five grams of creatine four times a day, for five to six days. The dose is maintained with of two grams a day to replace daily turnover. However, initial loading dose suggestions vary anywhere from nine grams to 20 grams during the first five days of training. An athlete's dose should be based on the advice of a personal trainer. A continuous low maintenance dose of three grams daily for 28 days is also recommended as an effective routine.

Drinking enough fluid is extremely important to a person taking creatine supplements. Two litres of water per day is suggested. This helps in avoiding the common problem of dehydration and associated stomach upset and muscle cramps.

People who should not use creatine include those with a history of kidney or liver problems, athletes recovering from soft tissue injuries, or those under 18 years of age. Anyone taking drugs that damage the kidneys, such as nonsteriodal and anti-inflammatory drugs, cyclosporine, or the ACE inhibitor class of blood pressure medications, should not take creatine.

Athletes can have varied responses to creatine supplements, possibly related to differences in diet. Taking creatine is not a short cut for sound training and nutrition program.

The finish line

Several aids that improve performance and quick fixes are available to today's athlete. Still, it is proper nutrition, including proper fluid replacement that is critical to the best performance in sports. If necessary, supplements may be added to a routine. With any performance-improving agents, herbal preparations, and even vitamins and minerals, the advice of your doctor, dietitian, and pharmacist should be considered. Many agents cannot be used by those taking certain medications or with certain conditions. A prior assessment by a health care professional is important.

Whether you are a recreational or professional athlete, exercise offers rewarding benefits. The advice of a health professional can help ensure your peak performance is kept on track.

High protein diets often displace the amount of carbohydrate eaten and can cause dehydration. Both hamper athletic performance. The list of long-term side effects and health concerns are other arguments against loading up on protein.

Kristen Orquia, a University of Alberta pharmacy student: Darcy Wruk, BSc (Pharm), a pharmacy manager in Sherwood Park, Alberta; and Kelly Anne Erdman, MSc, a registered dietitian at the University of Calgary Sport Medicine Centre, Alberta, and a former Olympic cyclist. Copyright 2005 Micromedia Limited Canadian Business and Current Affairs Copyright 2005 Edmonton Journal Family Health July 1, 2005