Center for Young Women's Health

Sports Nutrition & Fitness FAQ's



  • Your body needs carbs, proteins, fats, minerals, vitamins, and water for good health.
  • Fuel your body before, during, and after exercise.
  • Athletes need more food and fluids than non-athletes.

Every day we receive questions from teens all over the world. We've answered some of the most common fitness and sports nutrition questions below.


Sports Nutrition

Should I drink sports drinks when I exercise?

Is there such a thing as drinking too much water?

Do athletes need to follow a strict diet to perform well?

Should I eat energy bars?

Should I eat extra protein?

Should I carb-load before my games or competitions?

What should I eat before a game/practice?

What should I eat after a game/practice?



Do I need to lift heavy weights to build muscle?

How can I lose weight just in my stomach?

How can I strengthen my abs?

Why do boys seem to get more muscular than girls?

Do I need to stretch when I exercise? I'm not flexible at all.

What are shin splints and how do I avoid getting them?

What are the best exercises for weight loss?

I am thinking of taking a kickboxing class. Can anyone try this?

Is yoga good for you?

Are yoga or exercise balls good to use for toning your body?

How do I fit exercise into my busy schedule?

What should I do if I feel too tired to exercise?

Should I eat before I exercise?

How often do I need to exercise?



Sports Nutrition


Should I drink sports drinks when I exercise?

Water is usually the best fluid for your body. When you exercise intensely or in the heat for longer than an hour, though, you may need to replace the carbohydrates used to fuel exercise and the electrolytes lost in sweat. Drinking sports drinks (such as Gatorade® or Powerade®) that have carbohydrates and electrolytes is a great way to hydrate during exercise that lasts longer than an hour. Make sure to pay special attention to how much you’re sweating; the more you sweat, the more you’ll need to drink to stay hydrated. If you're working out for less than an hour, water and a well-balanced meal after your workout will replace the fluid and energy that your body used while exercising. Sports drinks such as Gatorade G2®, Propel®, Vitamin Water 10®, and Powerade Zero® provide electrolytes, but they are either low in carbohydrates or have no carbohydrates in them, so they are fine to drink during shorter workouts.



Is there such a thing as drinking too much water?Back to Top

The term for drinking too much water is: “water intoxication”. This condition is rare, but can happen when a person drinks a huge amount of water in a short period of time (equivalent to drinking 5- 10 two liter bottles within a few hours). Having this much water can cause the sodium (salt) levels in the body to drop (a condition known as hyponatremia). When this happens, the cells in the body begin to swell which can cause confusion, severe headaches, dizziness, nausea, vomiting, bloating, seizures, comas, and even death.


It's important for athletes to drink plenty of fluids to prevent dehydration. However, athletes who are active for long periods of time could be at risk for water intoxication if they don’t include some food or fluids that have sodium in them to replace the sodium that's lost from sweating. This condition can easily be avoided by eating a small snack or drinking a sports drink during long periods of physical activity. Tell someone immediately if you get a headache, or feel nauseous or dizzy during exercise.



Do athletes need to follow a strict diet to perform well?Back to Top

No. An athlete's diet should be very similar to a regular well-balanced diet, except:

Should I eat energy bars?Back to Top

It depends. There are many different energy bars you can buy. Some are high in carbohydrates and others are high in protein. They do not contain any magic ingredient that will help your athletic performance. Regular foods that have some carbohydrate and protein in them such as yogurt, cheese and crackers, or peanut butter on toast are just as good and usually cost less. However, energy bars are convenient and may taste good. If you're eating them for those reasons, then they are fine. Energy bars are usually pretty dense and low in moisture so make sure you drink plenty of fluids when you eat them.


Should I eat extra protein?Back to Top

Although protein is needed to build muscle, most people eat plenty of protein and eating extra will not have any benefit. For most people, 5 ounces of protein foods (such as meat, poultry, fish, beans, tofu, or eggs) every day and 3-4 ounces of dairy protein (such as milk, yogurt, or cheese) will provide enough protein. Eating enough calories is actually more important for building muscle. Without enough calories, your body can't build new muscle.


Should I carb-load before my games or competitions?Back to Top

When you are training or competing, your muscles need energy to perform. Glycogen, which is glucose stored in our muscles and liver, is the energy used by muscles. Every time you work out, you use some of your glycogen. If you don't eat enough carbohydrates, you'll have fewer glycogen stores, and your muscles may not be able to perform their best.


Carbohydrate loading is a technique used to increase the amount of glycogen in muscles and in the liver. It involves eating extra carbohydrates during the week before a competition while at the same time cutting back on training. Carb-loading is intended for elite athletes such as marathon runners and isn't necessary for most athletes.


What should I eat before a game/practice?Back to Top

Performance depends mostly on the foods you ate in the days and weeks leading up to an event. If you usually eat a well-balanced diet with plenty of carbohydrates, you will probably have enough energy (glycogen) stored in your body to perform well. The purpose of the "pre-competition" meal is to prevent hunger and to give you the water and energy you will need during the game/practice. If you tend to get nervous before a competition or event you may also want to focus on eating foods that are gentle on the stomach before the event.


There is no magic pre-exercise diet, so use your own experience to figure out which foods work best for you. Some general tips for eating before games/practices are:


What should I eat after a game/practice?Back to Top

After a game/practice you'll need to replace the carbohydrate burned and the electrolytes lost. Electrolytes are found in nearly all foods, so you don't need to buy a special drink. Your body will replenish its energy stores (glycogen) the best if you eat a food with carbohydrates and some protein after working out such as a half of a sandwich that contains lean protein, a glass of chocolate milk, or a cheese stick and a granola bar.




Do I need to lift heavy weights to build muscle?Back to Top

No. You don't need to lift heavy weights to strengthen and tone muscles on your body. You can build muscles by doing toning exercises, lifting light weights, or playing sports. You can even strengthen certain muscle groups by doing activities such as cleaning your room and carrying your book bag.


How can I lose weight just in my stomach?Back to Top

There are no exercises or nutrition plans that can target weight loss to a specific area of your body, like your stomach. You can strengthen your core stomach muscles, and this will help your abs be stronger.


How can I strengthen my abs?Back to Top

Firming your abdominal area takes a regular exercise routine and time. Simple abdominal crunches or sit-ups are easy and effective. You do not need to buy fancy ab equipment. Combining cardio (exercises that make you sweat) with ab training will build muscle and burn stored adipose (fat) tissue. Strong abs also help prevent back injuries.


Why do boys seem to get more muscular than girls? (I go to the gym with my guy friends and they are seeing results faster than I am.)Back to Top

It's true; males build muscle faster than females do. This is because guys have more testosterone, a male hormone, which helps form muscle. Since women naturally have less testosterone, they build muscle at a slower pace. Girls can build strong muscles by exercising regularly and eating a balanced diet.


Do I need to stretch when I exercise? I'm not flexible at all.Back to Top

Yes. Proper stretching before and after exercise is important for preventing injuries in all your muscle groups (upper, mid, and lower body). It also decreases your risk of back injury. You will see improvements in flexibility over time. Everyone has the potential to become more flexible.


My friend told me that the pain I feel in the front of my lower legs is really shin splints. What are shin splints and how do I avoid getting them?Back to Top

"Shin splints" is a term used to describe any pain in the shins, the area in the front of the lower leg below the knee. You usually feel shin splints 2 to 24 hours after aerobic exercise. You can avoid getting shin splints by making sure to stretch before and after any aerobic exercise and wearing sneakers with good support. Listen to your body when you are exercising. If the exercise causes pain, stop immediately.


What are the best exercises for weight loss?Back to Top

There is no magic workout for weight loss, but cross training is a healthy plan. Cross training means balancing a variety of cardiovascular, muscle conditioning, and flexibility activities. This prevents boredom, so you will stick with your fitness routine.


Cardiovascular activities are exercises that use your heart muscle, burn energy, and build muscle. These include: sports, cheerleading, power walking, running, dancing, or other exercises that make you sweat.


Muscle conditioning exercises include weight lifting and toning exercises such as pushups, sit-ups, or leg lifts. Playing sports and doing yoga can build muscles too. Building muscle raises your metabolism (how your body burns food for energy), and may help prevent osteoporosis (thinning of the bones).


Flexibility exercises stretch your muscles. Injury prevention is an important benefit of stretching.


I am thinking of taking a kickboxing class. Can anyone try this?Back to Top

Kickboxing is a great exercise for everyone, no matter what your fitness level is. During class, you will learn fun cardio moves that tone the legs, abs, and upper-body. It's a great way to release stress and learn self-defense moves at the same time.


Is yoga good for you?Back to Top

Yoga is excellent for health. It combines stretching, muscle toning, and breathing. Yoga relaxes the body and helps you feel less stressed. You don't need fancy equipment in order to try yoga poses and breathing techniques. You can watch a yoga video or take a class.


Are yoga or exercise balls good to use for toning your body?Back to Top

Yoga balls, also known as stability or exercise balls, are a great way to add variety to your muscle conditioning routine. A yoga ball can be used to support your back when you are doing abdominal exercises. You can also sit on the ball, using it like a chair, when you are doing upper body (arms and back) exercises with weights. When doing muscle exercises for the upper body, the yoga ball keeps your core muscles (middle body) working hard. You can even use the yoga ball for different stretches for your back and abs. Make sure you receive proper instruction on your form from a fitness instructor or coach before trying the yoga ball.


How do I fit exercise into my busy schedule?Back to Top

Here are some ideas to start with:

What should I do if I feel too tired to exercise?Back to Top

Try to exercise even if you feel tired. Listening to music can help motivate you! When you exercise, you usually sleep better at night and will have more energy later. Exercise actually gives you more energy in the long run.


Should I eat before I exercise?Back to Top

If you have not eaten for several hours, you should have a snack and water before you start working out. Try something with carbohydrates such as a granola bar, fruit, peanut butter and crackers, or yogurt. Drink about 1 cup (8oz.) of fluid. This is quick and easy fuel for exercising. See our Sports and Nutrition guide for more information.


How often do I need to exercise?Back to Top

Teens should aim to include at least 60 minutes of physical activity on most days of the week.


Written and reviewed by the CYWH Staff at Boston Children's Hospital


Updated: 12/12/2013


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