NOTA di WNC2: Essendo un articolo "sponsorizzato" da Powerbar, ovviamente nei suggerimenti alimentari si consigliano prodotti Powerbar, sebbene sia un marchio molto mirato al ciclismo, la scelta del prodotto non è ovviamente vincolate.
By: Kelly Pritchett, PhD, RD, CSSD
Board Certified Specialist in Sports Dietetics, Assistant Professor in Exercise Science and Nutrition
“Don’t eat to keep up with your competitors — eat to win!”
As a sports dietitian working with teenage athletes, I tend to get a lot of questions concerning nutrition and its effects on performance. The following were submitted to me by the DyeStat online track-and-field community. Though the questions came from track-and-field athletes, the answers can be applied to many high school and college team sports and training exercises.
1. What is “carb loading?” Does it really help?
Most people tend to associate carb loading with eating almost no carbohydrates from 4–7 days prior to a big endurance event, then switching to consuming large quantities of carbohydrates (potatoes, rice, pasta, bread) for the final 4 days before the event. This describes the old method of carb loading. In the new method, the athlete simply increases carbohydrate intake prior to an event, while decreasing training volume. By increasing carbohydrates in the diet, adult athletes are able to maximize amounts stored as glycogen (the body’s “high-octane fuel”
in the muscles. Athletes typically deplete their glycogen stores when they exercise longer than 90 minutes without any food. Therefore, endurance athletes participating in events lasting longer than 90 minutes may benefit from carb loading.
In general, carbohydrate loading is not necessary for track-and-field athletes because the events are not long enough to deplete glycogen levels. The disadvantages of carb loading may outweigh the advantages due to common side effects of major dietary changes, such as water-weight gain, stiffness, nausea, and diarrhea. Young athletes that are concerned about this can ensure sufficient glycogen stores by slightly or moderately increasing their dietary intake of starchy foods and reducing training 24–48 hours prior to their events.
2. What and when do I eat on race day?
No matter what you eat on race day, it’s very important to provide energy for the event and to be confident that your body is properly fueled. Many athletes have a “magic meal” that they like to eat on race day. This is a meal that they have already tested on numerous occasions that works for them. It’s important not to try anything new on race day. If you don’t already have a good pre-event meal, test one by scheduling a few workouts that are similar to your event to see how your body responds to it. If you have an early-morning event or a queasy stomach, it is unrealistic to consume a large meal; therefore, it becomes important to consume a high-carbohydrate meal, such as pasta, the evening before your event. For such athletes, a pre-event carbohydrate-rich smoothie or liquid protein/carbohydrate meal may be better tolerated. In general, 200–300 calories of carbohydrates (50–75 grams) consumed an hour or 2 before an event has been shown to work for a majority of athletes. The following are examples of pre-race meals:
3. Does soda really adversely affect runners?
Sodas have a lot of sugar and many have caffeine. The sugar levels are typically high, and may lead to an upset stomach if consumed too near to race time. It is better to consume a sports beverage, which contains sodium and a more effective concentration and blend of sugars.
Regarding caffeine, research suggests that endurance athletes participating in events lasting more than an an hour may benefit from a small amount (100 mg) of caffeine. Caffeine works by decreasing the perception of effort during exercise, therefore allowing the athlete to perform at a higher intensity. However, there is no research supporting the safety and effectiveness of its use by high school athletes. High doses of caffeine are also known to cause nervousness, an upset stomach, difficulty in sleeping, anxiety, or rapid heartbeat in some individuals. If you choose to try products with caffeine, it’s important to test them in practice before using them in competition.
4. What makes a good recovery drink?
Choosing your foods wisely after a race or workout will help you recover more quickly next time. To replace your muscles’ glycogen (energy) stores, it is recommended that you drink or eat carbohydrates and protein within 30 minutes after exercise. Around 6–8 grams of protein (the amount in 2 slices of turkey or a cup of low-fat chocolate milk) taken in combination with high-carbohydrate foods is the best way to maximize recovery. In addition, consume another small carb/protein meal within the second hour after your workout. The availability of amino acids from protein may help with muscle repair and optimize recovery after exercise. Low-fat chocolate milk is a great example of a cost-effective and convenient recovery beverage. For instance, a gallon of chocolate milk costs only about $3, and an 8-fl-oz serving has 30 grams of carbohydrates and 8 grams of protein. If you don’t like chocolate, then strawberry-flavored Nesquik® or Carnation® Instant Breakfast Essentials™ (which comes in a variety of flavors) mixed with milk are great, affordable options.
5. Which supplements are okay to take, and which are a waste of time? What about caffeine?
The goal for — or perhaps the pressure on — many young athletes is to perform faster and stronger. We are constantly bombarded with ads for supplements that promise to give you that edge. Many athletes resort to powders and pills, without really knowing what they are or how they work, and some believe they can substitute them for a balanced, healthful diet. Athletes should first look at their overall diets and see where there are opportunities for improvement. An athlete can make huge gains in performance by using sound sports nutrition strategies, as outlined in the PowerBar Nutrition Coach Teaching Guide. If you follow these strategies, then normal multi-vitamin and mineral supplements that provide about 100% of your recommended daily values are okay to take — for insurance — but could also be a waste of time if you maintain a good diet. High-dose nutrients are probably just a waste of time unless you don’t eat dairy and need extra calcium, or if you are a teenage female and need supplemental iron.
If you are considering supplements to help enhance your performance, you should be extremely careful: Many substances are present in these supplements that could lead to a positive drug test. This could be the difference between an NCAA Division I full ride and a community college bench seat. To be safe, look for the NSF Certified for Sport™ on the label, which ensures that each batch is tested, is free of banned substances, and contains exactly what is on the label. (www.nsf.org) Also, see Question 6 below.
Two of the most commonly used supplements are creatine and caffeine.
The effects ascribed to using creatine are increased strength and muscle mass. It is found naturally in meat and fish. A research overview of many studies shows that creatine is useful for increasing muscle when you are doing repeated short-duration, high-intensity exercise. While creatine seems to be safe for use by adults, there is little or no research supporting its safety and effectiveness in athletes under 18 years old, so you may be better off just skipping it for now.
Caffeine is used as an ergogenic aid to improve endurance performance because it slightly increases your tolerance for pain. It is essential to know the adverse side effects of using higher doses of caffeine, such as nervousness, irritability, an upset stomach, and headaches. It is also important to note that the NCAA prohibits the use of caffeine in higher doses. While caffeine is considered safe to use by adults, again, there is little research supporting its safety and effectiveness in teenage athletes. If you do use products with caffeine, keep the dose between 50 and 100 mg.
6. I am a college athlete. I was wondering why my NCAA compliance officer told me to avoid vitaminwater®?
In January of 2009, the NCAA Convention informed its members that 6 flavors of vitaminwater® contained non-permissible substances. A non-permissible substance cannot be provided by the schools to student athletes. The NCAA considers caffeine and added amino acids as non-permissible, so the flavors with caffeine or added taurine and theanine are not allowed. These varieties may be purchased and consumed by student athletes on their own without any risk to their NCAA eligibility.
Banned or Non-Permissible Vitaminwater Flavors:
Energy Tropical Citrus (contains caffeine and guarana seed extract)
Rescue Green Tea (contains caffeine, green tea extract, and ECGC)
Power-C Dragon Fruit (contains taurine)
B-Relaxed Jackfruit Guava (contains theanine)
Vital-T Lemon Tea-Rooibos (contains rooibos tea extract)
Balance Cran-Grapefruit (contains glucosamine)
NCAA-Approved Vitaminwater Flavors:
Revive: Fruit Punch
Essential: Orange-Orange
XXX: Acai-Blueberry-Pomegranate
Focus: Kiwi Strawberry
Formula 50: Grape
Multi-V: Lemonade
Charge: Lemon-Lime
Endurance: Peach-Mango
Defense: Raspberry-Mango *
* il paragrafo 7 riguarda solo una regola NCAA (gli atleti universitari americani)
7. How does alcohol affect athletic performance/training long term?
Alcohol is discouraged since all high school athletes and many college athletes are below the legal drinking age. It is considered to be a drug because of the harmful effects it has on the central nervous system (the brain and the spinal cord). It contains 7 calories per gram, almost as many as fat and nearly twice as many as carbohydrates and protein. Therefore, alcohol is just empty calories with no nutritional value. It is also known to increase appetite, which results in the consumption of more calories during or after drinking. From a performance perspective, it is detrimental: Your caloric intake should be from nutrient-dense foods. It is also a myth that alcohol is high in carbohydrates and therefore good for athletes: A beer contains only around 10–12 grams of carbs, so it is not a good source of carbohydrates for replacing glycogen stores after a workout.
8. What are the best foods to eat within an hour of competition? What about during competition (for field event athletes)?
Eating before competition provides many benefits to the athlete. The pre-exercise meal will provide energy during competition; help prevent hypoglycemia (low blood sugar), which can interfere with performance; fuel your muscles; help settle your stomach by absorbing gastric juices; help curb hunger; and top off glycogen stores. In general, it is recommended to eat 40–80 grams of carbohydrates 1 hour before exercise to top off your energy stores. The following are examples of pre-exercise fueling options that can be consumed 1 hour before an event:
Eating during events for field-event athletes will provide energy and increase your stamina. This is particularly helpful during a long competition day whereyou are competing in multiple events. It is recommended to consume 30–60 grams of carbohydrates per hour during competition. The following are examples of meals meeting this recommendation:
9. Which sports drinks are best? Which are worst?
It is important to understand the difference between sports drinks and energy drinks. Sports drinks contain 4%–8% carbohydrates plus electrolytes. They are recommended when exercising in the heat, or when exercising for more than 60 minutes. These beverages have the optimal amounts of carbohydrates (including sugars) and electrolytes (especially sodium) lost in sweat, to help prevent dehydration. On the other hand, energy drinks such as Monster Energy® drink and Rockstar Energy Drink® contain extra sugar and caffeine. They are considered to be empty calories and have not been shown to enhance exercise performance.
To determine your fluid needs during exercise, weigh yourself before and after exercise to assess sweat loss per hour. For every 1 lb lost, drink 2 cups (16 fl oz) of water. You can space this out throughout the exercise session. For example, if you lose an average of 2 lbs during an hour of exercise, you need 4 cups of fluid. You could drink 1 cup of fluid every 15 minutes throughout the workout. To determine whether you are adequately hydrated, make sure your urine color is pale yellow or lighter. If you are taking a multi-vitamin supplement with B vitamins, it will be darker. If you are not taking a B vitamin or haven’t taken one in a few hours, and your urine is about the color of apple juice, more fluids are needed.
There are many different commercial sports drinks available. They contain various types and amounts of sugars and electrolytes. Whether they offer advantages over plain water depends on how intensive the sport or event is. For the less-intense sports with periods of rest, plain water is all that an athlete needs. In fact, the more highly concentrated sports drinks can delay fluid absorption. Also, avoid drinks that contain only glucose or only fructose as their single source of carbohydrates. It is better to have a beverage with a mixture of carbohydrate sources, such as glucose and fructose combined. And remember, for endurance athletes, a good sports drink is recommended to help keep you hydrated and fueled to perform at your best.
10. Are multi-vitamins good for you?
In general, athletes that have a balanced diet which meets their nutritional needs do not need a multi-vitamin. However, high school and college athletes may not get enough calcium and iron. By consuming 3 servings of dairy/calcium-fortified foods, like milk or calcium-fortified orange juice, athletes will likely meet their calcium needs. Iron requirements are higher during puberty, but can be met by eating a variety of foods that contain iron-fortified grains, such as cereals, breads, and sports bars. There is no harm in taking a once-daily multi-vitamin as extra nutritional insurance, but don’t substitute pills for a balanced diet.
By: Kelly Pritchett, PhD, RD, CSSD
Board Certified Specialist in Sports Dietetics, Assistant Professor in Exercise Science and Nutrition
“Don’t eat to keep up with your competitors — eat to win!”
As a sports dietitian working with teenage athletes, I tend to get a lot of questions concerning nutrition and its effects on performance. The following were submitted to me by the DyeStat online track-and-field community. Though the questions came from track-and-field athletes, the answers can be applied to many high school and college team sports and training exercises.
1. What is “carb loading?” Does it really help?
Most people tend to associate carb loading with eating almost no carbohydrates from 4–7 days prior to a big endurance event, then switching to consuming large quantities of carbohydrates (potatoes, rice, pasta, bread) for the final 4 days before the event. This describes the old method of carb loading. In the new method, the athlete simply increases carbohydrate intake prior to an event, while decreasing training volume. By increasing carbohydrates in the diet, adult athletes are able to maximize amounts stored as glycogen (the body’s “high-octane fuel”
in the muscles. Athletes typically deplete their glycogen stores when they exercise longer than 90 minutes without any food. Therefore, endurance athletes participating in events lasting longer than 90 minutes may benefit from carb loading.In general, carbohydrate loading is not necessary for track-and-field athletes because the events are not long enough to deplete glycogen levels. The disadvantages of carb loading may outweigh the advantages due to common side effects of major dietary changes, such as water-weight gain, stiffness, nausea, and diarrhea. Young athletes that are concerned about this can ensure sufficient glycogen stores by slightly or moderately increasing their dietary intake of starchy foods and reducing training 24–48 hours prior to their events.
2. What and when do I eat on race day?
No matter what you eat on race day, it’s very important to provide energy for the event and to be confident that your body is properly fueled. Many athletes have a “magic meal” that they like to eat on race day. This is a meal that they have already tested on numerous occasions that works for them. It’s important not to try anything new on race day. If you don’t already have a good pre-event meal, test one by scheduling a few workouts that are similar to your event to see how your body responds to it. If you have an early-morning event or a queasy stomach, it is unrealistic to consume a large meal; therefore, it becomes important to consume a high-carbohydrate meal, such as pasta, the evening before your event. For such athletes, a pre-event carbohydrate-rich smoothie or liquid protein/carbohydrate meal may be better tolerated. In general, 200–300 calories of carbohydrates (50–75 grams) consumed an hour or 2 before an event has been shown to work for a majority of athletes. The following are examples of pre-race meals:
- Instant oatmeal with low-fat milk
- Pancakes, fresh fruit, and low-fat milk
- Oatmeal, raisins, and low-fat milk
- English muffin with cheese
- 1 whole grain bagel with peanut butter and jelly
- Cereal with low-fat milk, and orange juice
- Low-fat yogurt, fruit, and granola
- Smoothie mixed with milk or juice, with fresh or frozen fruit
- ½ baked potato with low-fat cheese
- 1–2 PowerBar® Performance Energy bars
- Cottage cheese, toast, and fruit
- Turkey sandwich and applesauce
3. Does soda really adversely affect runners?
Sodas have a lot of sugar and many have caffeine. The sugar levels are typically high, and may lead to an upset stomach if consumed too near to race time. It is better to consume a sports beverage, which contains sodium and a more effective concentration and blend of sugars.
Regarding caffeine, research suggests that endurance athletes participating in events lasting more than an an hour may benefit from a small amount (100 mg) of caffeine. Caffeine works by decreasing the perception of effort during exercise, therefore allowing the athlete to perform at a higher intensity. However, there is no research supporting the safety and effectiveness of its use by high school athletes. High doses of caffeine are also known to cause nervousness, an upset stomach, difficulty in sleeping, anxiety, or rapid heartbeat in some individuals. If you choose to try products with caffeine, it’s important to test them in practice before using them in competition.
4. What makes a good recovery drink?
Choosing your foods wisely after a race or workout will help you recover more quickly next time. To replace your muscles’ glycogen (energy) stores, it is recommended that you drink or eat carbohydrates and protein within 30 minutes after exercise. Around 6–8 grams of protein (the amount in 2 slices of turkey or a cup of low-fat chocolate milk) taken in combination with high-carbohydrate foods is the best way to maximize recovery. In addition, consume another small carb/protein meal within the second hour after your workout. The availability of amino acids from protein may help with muscle repair and optimize recovery after exercise. Low-fat chocolate milk is a great example of a cost-effective and convenient recovery beverage. For instance, a gallon of chocolate milk costs only about $3, and an 8-fl-oz serving has 30 grams of carbohydrates and 8 grams of protein. If you don’t like chocolate, then strawberry-flavored Nesquik® or Carnation® Instant Breakfast Essentials™ (which comes in a variety of flavors) mixed with milk are great, affordable options.
5. Which supplements are okay to take, and which are a waste of time? What about caffeine?
The goal for — or perhaps the pressure on — many young athletes is to perform faster and stronger. We are constantly bombarded with ads for supplements that promise to give you that edge. Many athletes resort to powders and pills, without really knowing what they are or how they work, and some believe they can substitute them for a balanced, healthful diet. Athletes should first look at their overall diets and see where there are opportunities for improvement. An athlete can make huge gains in performance by using sound sports nutrition strategies, as outlined in the PowerBar Nutrition Coach Teaching Guide. If you follow these strategies, then normal multi-vitamin and mineral supplements that provide about 100% of your recommended daily values are okay to take — for insurance — but could also be a waste of time if you maintain a good diet. High-dose nutrients are probably just a waste of time unless you don’t eat dairy and need extra calcium, or if you are a teenage female and need supplemental iron.
If you are considering supplements to help enhance your performance, you should be extremely careful: Many substances are present in these supplements that could lead to a positive drug test. This could be the difference between an NCAA Division I full ride and a community college bench seat. To be safe, look for the NSF Certified for Sport™ on the label, which ensures that each batch is tested, is free of banned substances, and contains exactly what is on the label. (www.nsf.org) Also, see Question 6 below.
Two of the most commonly used supplements are creatine and caffeine.
The effects ascribed to using creatine are increased strength and muscle mass. It is found naturally in meat and fish. A research overview of many studies shows that creatine is useful for increasing muscle when you are doing repeated short-duration, high-intensity exercise. While creatine seems to be safe for use by adults, there is little or no research supporting its safety and effectiveness in athletes under 18 years old, so you may be better off just skipping it for now.
Caffeine is used as an ergogenic aid to improve endurance performance because it slightly increases your tolerance for pain. It is essential to know the adverse side effects of using higher doses of caffeine, such as nervousness, irritability, an upset stomach, and headaches. It is also important to note that the NCAA prohibits the use of caffeine in higher doses. While caffeine is considered safe to use by adults, again, there is little research supporting its safety and effectiveness in teenage athletes. If you do use products with caffeine, keep the dose between 50 and 100 mg.
6. I am a college athlete. I was wondering why my NCAA compliance officer told me to avoid vitaminwater®?
In January of 2009, the NCAA Convention informed its members that 6 flavors of vitaminwater® contained non-permissible substances. A non-permissible substance cannot be provided by the schools to student athletes. The NCAA considers caffeine and added amino acids as non-permissible, so the flavors with caffeine or added taurine and theanine are not allowed. These varieties may be purchased and consumed by student athletes on their own without any risk to their NCAA eligibility.
Banned or Non-Permissible Vitaminwater Flavors:
Energy Tropical Citrus (contains caffeine and guarana seed extract)
Rescue Green Tea (contains caffeine, green tea extract, and ECGC)
Power-C Dragon Fruit (contains taurine)
B-Relaxed Jackfruit Guava (contains theanine)
Vital-T Lemon Tea-Rooibos (contains rooibos tea extract)
Balance Cran-Grapefruit (contains glucosamine)
NCAA-Approved Vitaminwater Flavors:
Revive: Fruit Punch
Essential: Orange-Orange
XXX: Acai-Blueberry-Pomegranate
Focus: Kiwi Strawberry
Formula 50: Grape
Multi-V: Lemonade
Charge: Lemon-Lime
Endurance: Peach-Mango
Defense: Raspberry-Mango *
* il paragrafo 7 riguarda solo una regola NCAA (gli atleti universitari americani)
7. How does alcohol affect athletic performance/training long term?
Alcohol is discouraged since all high school athletes and many college athletes are below the legal drinking age. It is considered to be a drug because of the harmful effects it has on the central nervous system (the brain and the spinal cord). It contains 7 calories per gram, almost as many as fat and nearly twice as many as carbohydrates and protein. Therefore, alcohol is just empty calories with no nutritional value. It is also known to increase appetite, which results in the consumption of more calories during or after drinking. From a performance perspective, it is detrimental: Your caloric intake should be from nutrient-dense foods. It is also a myth that alcohol is high in carbohydrates and therefore good for athletes: A beer contains only around 10–12 grams of carbs, so it is not a good source of carbohydrates for replacing glycogen stores after a workout.
8. What are the best foods to eat within an hour of competition? What about during competition (for field event athletes)?
Eating before competition provides many benefits to the athlete. The pre-exercise meal will provide energy during competition; help prevent hypoglycemia (low blood sugar), which can interfere with performance; fuel your muscles; help settle your stomach by absorbing gastric juices; help curb hunger; and top off glycogen stores. In general, it is recommended to eat 40–80 grams of carbohydrates 1 hour before exercise to top off your energy stores. The following are examples of pre-exercise fueling options that can be consumed 1 hour before an event:
- 1 large banana with 1 tbsp low-fat peanut butter
- Trail mix with nuts and dried fruit
- English muffin with low fat peanut butter and jelly
- ½ plain bagel with cheese
- 1 apple with string cheese and rice crackers
- ½ cup of oatmeal with low-fat milk
- Smoothie mixed with milk or juice, with fresh or frozen fruit
- 1 PowerBar® Performance Energy bar
- 1 PowerBar® Fruit Smoothie Energy bar
- PowerBar® Energy bites (1 package)
- PowerBar® Gel Blasts™ energy chews (1 package)
Eating during events for field-event athletes will provide energy and increase your stamina. This is particularly helpful during a long competition day whereyou are competing in multiple events. It is recommended to consume 30–60 grams of carbohydrates per hour during competition. The following are examples of meals meeting this recommendation:
- 1 banana, and 2 cups of sports drink (PowerBar® Endurance sports drink)
- 1–1½ energy bars (PowerBar Performance Energy bar)
- 4 cups of a sports drink
- 1 pack of PowerBar® Gel Blasts™ energy chews
- 1–2 gel packets (PowerBar® Gels)
- ½ bagel and 1 cup of a sports drink
9. Which sports drinks are best? Which are worst?
It is important to understand the difference between sports drinks and energy drinks. Sports drinks contain 4%–8% carbohydrates plus electrolytes. They are recommended when exercising in the heat, or when exercising for more than 60 minutes. These beverages have the optimal amounts of carbohydrates (including sugars) and electrolytes (especially sodium) lost in sweat, to help prevent dehydration. On the other hand, energy drinks such as Monster Energy® drink and Rockstar Energy Drink® contain extra sugar and caffeine. They are considered to be empty calories and have not been shown to enhance exercise performance.
To determine your fluid needs during exercise, weigh yourself before and after exercise to assess sweat loss per hour. For every 1 lb lost, drink 2 cups (16 fl oz) of water. You can space this out throughout the exercise session. For example, if you lose an average of 2 lbs during an hour of exercise, you need 4 cups of fluid. You could drink 1 cup of fluid every 15 minutes throughout the workout. To determine whether you are adequately hydrated, make sure your urine color is pale yellow or lighter. If you are taking a multi-vitamin supplement with B vitamins, it will be darker. If you are not taking a B vitamin or haven’t taken one in a few hours, and your urine is about the color of apple juice, more fluids are needed.
There are many different commercial sports drinks available. They contain various types and amounts of sugars and electrolytes. Whether they offer advantages over plain water depends on how intensive the sport or event is. For the less-intense sports with periods of rest, plain water is all that an athlete needs. In fact, the more highly concentrated sports drinks can delay fluid absorption. Also, avoid drinks that contain only glucose or only fructose as their single source of carbohydrates. It is better to have a beverage with a mixture of carbohydrate sources, such as glucose and fructose combined. And remember, for endurance athletes, a good sports drink is recommended to help keep you hydrated and fueled to perform at your best.
10. Are multi-vitamins good for you?
In general, athletes that have a balanced diet which meets their nutritional needs do not need a multi-vitamin. However, high school and college athletes may not get enough calcium and iron. By consuming 3 servings of dairy/calcium-fortified foods, like milk or calcium-fortified orange juice, athletes will likely meet their calcium needs. Iron requirements are higher during puberty, but can be met by eating a variety of foods that contain iron-fortified grains, such as cereals, breads, and sports bars. There is no harm in taking a once-daily multi-vitamin as extra nutritional insurance, but don’t substitute pills for a balanced diet.
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