Complex carbohydrates come from foods such as potatoes, beans, vegetables, whole grain pasta, cereals and other grain products. Simple carbohydrates are found in foods such as fruits, milk, honey and sugar.

During digestion, the body breaks down carbohydrates to glucose, which is then utilized for energy or converted to glycogen and stored in the muscles and liver to fulfill later energy needs. During exercise, stored glycogen is converted back to glucose and used for energy.

The body can only store a finite amount of carbohydrates as glycogen. The ability to sustain prolonged vigorous exercise is directly related to initial levels of muscle glycogen.

For events lasting less than two hours, the glycogen stores in muscles are typically sufficient to supply the needed energy. Extra carbohydrates will not help any more than adding gas to a half-full tank will make the car go faster. For events that require heavy work for more than two hours, a high-carbohydrate diet eaten for two to three days before the event allows glycogen storage spaces to be filled.

Endurance athletes, such as long distance runners, cyclists, swimmers, and cross-country skiers, report benefits from a pre-competition diet, in which 70 percent of the calories comes from carbohydrates. Research has demonstrated that endurance athletes on a high-carbohydrate diet can exercise longer than athletes eating a low-carbohydrate, high-fat diet.

However, constantly eating a high-carbohydrate diet is not advised. This conditions the body to use only carbohydrates for fuel and not the fatty acids derived from fats. For continuous activities of three to four hours, it is important that glycogen stores in the muscles and liver are at a maximum.

Additionally, taking carbohydrates during the event in the form of carbohydrate solutions, such as electrolyte drinks can be beneficial. The current recommendation is a 6 to 8 percent glucose solution. A homemade electrolyte drink with 7. Dissolve sugar and cool.

Sports drinks can be used to supply sodium and glucose if the athlete tolerates them, but other electrolytes are not essential until after the event.

Athletes should experiment during training to find if electrolyte beverages are right for them. Fat is also a significant contributor to energy needs. For moderate exercise, about half of the total energy expenditure is derived from free fatty acid metabolism. If the event lasts more than an hour, the body may use mostly fats for energy.

Furthermore, trained athletes use fat for energy more quickly than untrained athletes. Fat consumption should be a minimum of 20 percent of total energy intake to preserve athletic performance.

Maintaining adequate fat intake is crucial to meeting nutritional needs of essential fatty acids and fat-soluble vitamins, vitamins A, D, E and K. Athletes who are under pressure to achieve or maintain a low body weight are susceptible to using fat restriction and should be told that this may hinder their performance.

While adequate fat intake is necessary, claims that suggest a high-fat low-carbohydrate diet enhances athletic performance have not been supported by research.

When compared to fat and carbohydrates, protein contributes minimally to energy needs for the body.

Dietary protein is digested into amino acids, which are used as the building blocks for the different tissues, enzymes, and hormones that the body needs to function. It is important for muscle building and repair that occurs after exercise.

The current Recommended Daily Allowance RDA for protein is 0. However, the Academy for Nutrition and Dietetics and the American College of Sports Medicine recommend that endurance athletes eat between 1.

Eating protein after an athletic event has been shown to support muscle protein synthesis. However, eating protein in excess of nutritional needs has not been shown to further increase muscle building. Extra protein is broken down for energy or is stored as fat. A varied diet should provide more than enough protein as caloric intake increases.

However, vegetarian athletes should work with a dietitian to make sure their protein intake is sufficient. Excess protein can deprive the athlete of more efficient fuel sources and can lead to dehydration. High-protein diets increase the water requirement necessary to eliminate the nitrogen through the urine.

Also, an increase in metabolic rate can occur and, therefore, increased oxygen consumption. Protein and amino acid supplements are unnecessary and not recommended. However, this is typically excessive, because proteins needs are easily met in an American diet.

Eating whole foods instead of supplements is generally the best practice. Any athlete consuming supplements in replacement of meals should consult with their doctor or a registered dietitian before continuing. Water is an important nutrient for the athlete.

Water loss during an athletic event varies between individuals. Sweat loss can be tracked by measuring weight immediately before and after exercise. To avoid dehydration, an athlete should drink 5 to 7 mL per kilogram of body mass approximately four hours before an event.

Throughout the event, they should drink chilled water or electrolyte drinks, consuming enough to match sweat losses. Chilled fluids are absorbed faster and help lower body temperature.

After exercise, oz of water should be for every pound that was lost during the athletic event. By routinely tracking pre- and post- exercise weight changes, sweat rates can be estimated, allowing for more efficient hydration during athletic events.

An individual should never gain weight during exercise; this is a sign of excessive hydration, which can lead to electrolyte imbalances, and potentially hyponatremia.

It is important to account for environmental concerns when considering water consumption. Sweat rates may increase dramatically in hot and humid weather, and it is increasingly important for an athlete to stay hydrated in these conditions.

Competing at high altitudes also increases water needs. Athletes consuming sport drinks or energy drinks should be aware of caffeine levels. Limited amounts of caffeine have been shown to enhance athletic performance.

However, insomnia, restlessness and ringing of the ears can occur with caffeine consumption. Furthermore, caffeine acts as a diuretic and may cause the need to urinate during competition.

Maintaining adequate levels of vitamins and minerals is important for bodily function, and therefore, athletic performance. As the activity level of an athlete increases, the need for different vitamins and minerals may increase as well.

However, this need can be easily met by eating a balanced diet including a variety of foods. There is no evidence that taking more vitamins than is obtained by eating a variety of foods will improve performance.

B vitamins, including thiamin, riboflavin and niacin, are essential for producing energy from the fuel sources in the diet. Carbohydrate and protein foods are excellent sources of these vitamins. B vitamins are water soluble vitamins , which means that are not stored in the body, so toxicity is not an issue.

Some female athletes may lack riboflavin, so it is important to ensure adequate consumption of riboflavin-rich foods, like milk. Milk products not only increase the riboflavin level but also provide protein and calcium. Vitamin D has many functions in the body, and is crucial for calcium absorption.

Athletes who train indoors for prolonged periods of time should insure that they consuming adequate amounts of vitamin D through diet. Exercise increases the oxidative stress on the body, increasing the need for vitamins C and E, which have an antioxidant effect.

Vitamin E is a fat soluble vitamin , found in fats in the diet such as nuts, seeds, and vegetable oils. When an individual consumes excess fat-soluble vitamins A, D, E and K , they are stored in fat throughout the body.

Because they are stored, excessive amounts of fat-soluble vitamins may have toxic effects. Minerals play an important role in athletic function. Sodium is lost through the course of an athletic event through sweat, so it may be necessary to replace sodium in addition to water during an event.

Besides getting the right amount of calories, eating a variety of nutritious foods will help them play at their best. Most young athletes eat the right amount of food their bodies need.

Some young athletes, though, have higher energy and fluid needs. All-day competitions or intense endurance sports like rowing, cross-country running, or competitive swimming can involve 1½ to 2 hours or more of activity at a time.

Kids and teens who do these may need to eat more food to keep up with increased energy demands. The MyPlate food guide offers tips on what kinds of foods and drinks to include in your child's meals and snacks.

It's important for young athletes to drink plenty of fluids to prevent dehydration , which can zap strength, energy, and coordination and lead to heat-related illness. Even mild dehydration can affect athletic performance. Athletes can't rely on thirst to tell if they're getting dehydrated.

Thirst is a sign that their body has needed liquids for a while. Kids should drink water before physical activity and every 15 to 20 minutes throughout. They also should drink water afterward to restore fluid lost through sweat. Many sports drinks are available, but plain water is usually enough to keep kids hydrated.

Kids should avoid sugary drinks and carbonated beverages that can upset the stomach. Sports drinks can be a good choice for kids who do intense physical activity for more than 1 hour. Some school-age athletes face pressures involving nutrition and body weight. In some sports, it's common for kids to feel they need to increase or reduce their weight to reach peak performance.

In sports that emphasize weight or appearance, such as wrestling , swimming, dance, or gymnastics, kids may feel pressure to lose weight. Because athletic kids need extra fuel, it's usually not a good idea for them to diet. Unhealthy eating habits, like crash dieting, can leave kids with less strength and endurance and poor concentration.

The main role of carbohydrates in physical activity is to provide energy. For athletes, if their diet does not contain enough carbohydrate, it is likely that their performance and recovery will be impaired, as carbohydrate is the key fuel for the brain and for muscles during exercise.

The body can store carbohydrates in the muscles and liver as glycogen and use these stores as a source of fuel for physical activity. These glycogen stores are limited, so for those training at a high level, it is important to be fully fuelled at the start of any exercise.

Glycogen is the main source of energy at the start of exercise and during short bursts of exercise. If you are doing high intensity training for long periods and your glycogen stores are not sufficient you may feel tired, lack energy and not be able to perform at your best. So, regular intake of carbohydrate-rich foods can be important in this case to keep stores topped up.

The correct food choices can help ensure the body has enough energy for activity, as well as help aid recovery. Starchy foods are an important source of carbohydrates in our diet.

Wholegrain varieties also provide fibre, and a range of vitamins and minerals including B vitamins, iron, calcium and folate.

Find out more about this topic on our pages on starchy foods, sugar and fibre. The amount of carbohydrate you need will depend on the frequency, type, duration and intensity of physical activity you do. Competitive sports people and athletes will likely require more carbohydrates than an average gym user to match the intensity of their activity level.

If you are active at around the current recommended levels minutes of moderate activity or 75 minutes of high intensity activity plus two sessions of muscle strengthening activities per week , then you can follow general healthy eating guidance to base meals on starchy carbohydrates, choosing wholegrain and higher fibre options where possible.

For information about portion sizes of starchy foods you can use our Get portion wise! portion size guide. At this level of activity, it is unlikely you will need to consume extra carbohydrates by eating more or by using products like sports drinks or other carbohydrate supplements, and these can be counterproductive if you are trying to control your weight as they will contribute extra calories.

Sports drinks also contain sugars, which can damage teeth. Regardless of your level of activity, you should try not to meet your requirements by packing your entire carbohydrate intake into one meal.

Spread out your intake over breakfast, lunch, dinner and snacks that fit around planned exercise. For athletes and individuals who are recreationally active to a higher level such as training for a marathon , consuming additional carbohydrate may be beneficial for performance.

Athletes can benefit from having some carbohydrate both before and after exercise to ensure adequate carbohydrate at the start of training and to replenish glycogen stores post exercise.

In longer duration, high intensity exercise minutes or more , such as a football match or a marathon, consuming some carbohydrate during exercise can also improve performance, for example in the form of a sports drink.

Estimated carbohydrate needs are outlined below and depend on the intensity and duration of the exercise sessions International Olympics Committee :. For example, from this guidance, someone who weighs 70kg doing light activity would need g carbohydrate per day whereas if they were training at moderate to high intensity for 2 hours a day, they would need g carbohydrate per day.

Protein is important in sports performance as it can boost glycogen storage, reduce muscle soreness and promote muscle repair.

For those who are active regularly, there may be benefit from consuming a portion of protein at each mealtime and spreading protein intake out throughout the day. As some high protein foods can also be high in saturated fat, for example fatty meats or higher fat dairy products, it is important to choose lower fat options, such as lean meats.

Most vegans get enough protein from their diets, but it is important to consume a variety of plant proteins to ensure enough essential amino acids are included.

This is known as the complementary action of proteins. More information on vegetarian and vegan diets is available on our page on this topic. Whilst there may be a benefit in increasing protein intakes for athletes and those recreationally active to a high level, the importance of high protein diets is often overstated for the general population.

It is a common misconception that high protein intakes alone increase muscle mass and focussing too much on eating lots of protein can mean not getting enough carbohydrate, which is a more efficient source of energy for exercise.

It is important to note that high protein intakes can increase your energy calorie intake, which can lead to excess weight gain. The current protein recommendations for the general population are 0. If you are participating in regular sport and exercise like training for a running or cycling event or lifting weights regularly, then your protein requirements may be slightly higher than the general sedentary population, to promote muscle tissue growth and repair.

For strength and endurance athletes, protein requirements are increased to around 1. The most recent recommendations for athletes from the American College of Sports Medicine ACSM also focus on protein timing, not just total intake, ensuring high quality protein is consumed throughout the day after key exercise sessions and around every 3—5 hours over multiple meals, depending on requirements.

In athletes that are in energy deficit, such as team sport players trying to lose weight gained in the off season, there may be a benefit in consuming protein amounts at the high end, or slightly higher, than the recommendations, to reduce the loss of muscle mass during weight loss.

Timing of protein consumption is important in the recovery period after training for athletes. Between 30 minutes and 2 hours after training, it is recommended to consume g of protein alongside some carbohydrate. A whey protein shake contains around 20g of protein, which you can get from half a chicken breast or a small can of tuna.

For more information on protein supplements, see the supplements section. To date, there is no clear evidence to suggest that vegetarian or vegan diets impact performance differently to a mixed diet, although it is important to recognise that whatever the dietary pattern chosen, it is important to follow a diet that is balanced to meet nutrient requirements.

More research is needed, to determine whether vegetarian or vegan diets can help athletic performance. More plant-based diets can provide a wide variety of nutrients and natural phytochemicals, plenty of fibre and tend to be low in saturated fat, salt and sugar. Fat is essential for the body in small amounts, but it is also high in calories.

The type of fat consumed is also important. Studies have shown that replacing saturated fat with unsaturated fat in the diet can reduce blood cholesterol, which can lower the risk of heart disease and stroke. Fat-rich foods usually contain a mixture of saturated and unsaturated fatty acids but choosing foods that contain higher amounts of unsaturated fat and less saturated fat, is preferable as most of us eat too much saturated fat.

Find more information on fat on our pages on this nutrient. If I am doing endurance training, should I be following low carbohydrate, high fat diets? Carbohydrate is important as an energy source during exercise.

Having very low intakes of carbohydrate when exercising can cause low energy levels, loss of concentration, dizziness or irritability. Because carbohydrate is important for providing energy during exercise, there is a benefit in ensuring enough is consumed.