You may wonder if being physically active is really worth the time and effort. Well, lots of girls think so! They know being active is a great way to have fun and hang out with friends. And fitness can do some pretty amazing things for your mind and body.

What being active does for your mental health

Did you know being physically active can affect how good you feel? It also can affect how well you do your tasks, and even how pleasant you are to be around. That's partly because physical activity gets your brain to make "feel-good" chemicals called endorphins (say: en-DOR-fins). Regular physical activity may help you by:

• Reducing stress
• Improving sleep
• Boosting your energy
• Reducing symptoms of anxiety and depression
• Increasing your self-esteem
• Making you feel proud for taking good care of yourself
• Improving how well you do at school

What being active does for your body

Being physically active is great for your muscles, heart, and lungs. It may even help with nasty PMS symptoms! Some other possible benefits of activity include:

• Building strong bones. Your body creates the most bone when you are a kid and a teen. You can learn more about how to build great bones.
• Promoting a healthy weight. Obesity is a serious problem among kids in the United States. It can lead to problems with your sleep, knees, heart, emotions, and more, but exercise can help.
• Helping avoid diabetes. A lot more young people are getting diabetes than ever before. Regular physical activity can help prevent one type of diabetes.
• Building healthy habits. If you get used to being active now, you will more likely keep it up when you're older. You'll thank yourself later!
• Fighting cancer. Research shows that exercise may help protect against certain kinds of cancer, including breast cancer.
• Helping prevent high blood pressure. The number of kids with high blood pressure is growing. High blood pressure makes your heart and arteries work extra hard to pump blood. It also puts you at risk for things like kidney and eye disease.

Are you worried that exercise will bulk you up? Exercising won't give you big, bulging muscles. It takes a very intense weightlifting program to get a body-builder look. And exercise and other forms of physical activity can help if you need to lose weight or want to stay a healthy weight.

Regular physical activity (exercise) can help lower your risk for many diseases that affect women, including heart disease and stroke. Exercise can also help relieve symptoms of some conditions, such as depression, type 2 diabetes, and high blood pressure. Women need to do different types of physical activities to reach or stay at a healthy weight and build strength and endurance.

How can physical activity help my health?

Getting regular physical activity is one of the best things you can do for your health. Regular physical activity can help:

• Lower your blood pressure and cholesterol
• Lower your risk of dying early
• Help you lose weight (if you combine it with cutting calories) or keep your weight where it is as you get older
• Improve depression
• Improve sleep
• Lower your risk of diseases such as breast cancer, colon cancer, type 2 diabetes, heart disease, and stroke

How can physical activity help my health as I age?

Physical activity can help with your health when you get older. Regular physical activity helps:

• Keep bones strong
• Prevent hip fracture (breaking your hip)
• Decrease pain from arthritis
• Prevent dementia
• Maintain the independence to do basic everyday activities, like getting dressed, going to the bathroom, bathing, and eating

How much physical activity should I do?

Researchers know that the more physical activity you do, the more your health benefits. The more time you spend being active each week, the lower your risk is for dying early.

The Physical Activity Guidelines suggest that each week, women get at least:

• 2 hours and 30 minutes (150 minutes) of moderate-intensity aerobic physical activity. You know you are doing a moderate-intensity activity when your heart is beating faster but you can still carry on a conversation. Try a brisk, 30-minute walk five times a week.

OR

• 1 hour and 15 minutes (75 minutes) of vigorous-intensity aerobic activity. You know you are doing a vigorous-intensity physical activity when you are breathing hard and it is difficult to have a conversation. This could be a 40-minute jog or step class twice a week.

OR

• A combination of moderate- and vigorous-intensity aerobic activity

AND

• Muscle-strengthening activities on two or more days

You should aim for these amounts, but any physical activity is better than no physical activity. Try to spread your activity out over the week so that you are active on at least three days. You need to be active for at least 10 minutes at a time to get health benefits.

Physical activity should be in addition to the normal activities of daily living, such as cleaning, walking from the parking lot, or taking public transportation.

Can I exercise if I have underweight, overweight, or obesity?

Maybe. People who are underweight due to an eating disorder should not exercise unless their doctor tells them to. Your doctor or nurse can help you develop an exercise plan that is healthy and safe for a person of your current weight.

Women who have overweight or obesity should talk to their doctor or nurse about any concerns they have about beginning an exercise program. For most people, any amount or type of physical activity will help your overall health. Physical activity can also improve muscle strength, balance, and flexibility.

Can I exercise if I never have before?

Yes. Start slowly if you haven’t been physically active before or if it has been a while. Talk to your doctor or nurse about exercise if you have a health condition.

Talk to your doctor or nurse about ways you can fit physical activity into your life.

How much physical activity do I need to lose weight?

Everyone is different. How quickly you burn calories when you are physically active can be very different from other people, based on your specific genes, biology, and past. While scientists know that there are 3,500 calories in a pound, burning 500 extra calories every day (or 3,500 calories in a week) does not always result in losing exactly one pound. This is also true if you eat 500 fewer calories every day for a week, for a total of 3,500 fewer calories in one week.

Find a personalized healthy eating plan using the MyPlate Plan tool. The best way to lose weight is to combine healthy eating with exercise.

How much physical activity should I do if I’m trying to avoid weight gain?

Everyone is different. Physical activity is important to help you maintain your weight. But the amount of physical activity you need to stay the same weight depends on your specific genes, biology, past, and age.

Some women can maintain their weight by doing five hours or less of moderate-intensity activity a week. Some women may need to do more than five hours of moderate-intensity activity a week to stay at the same weight.

Talk to your doctor or nurse about how much physical activity you need and how to do it safely.

How can I avoid gaining weight after menopause?

As you age, and especially in the years after menopause, you may find it harder to maintain your weight. You may need to increase the amount of physical activity you get and lower how many calories you eat to stay the same weight.

What types of physical activity should I do to be healthy or lose weight?

You should do two types of physical activities on a regular basis: aerobic and muscle-strengthening activities.

Aerobic activities

Aerobic activities (also called “cardio”) make you breathe harder and your heart beat faster. During aerobic activities, such as running or dancing, you move your whole body, or a combination of arms and legs, over and over again.

Muscle-strengthening activities

Muscle-strengthening activities include working out with weight machines, free weights, or exercise bands. You also can do exercises that use your own body weight to create resistance, such as yoga, sit-ups, or push-ups.

The muscle you build helps you have the strength to do daily activities, such as climbing stairs or carrying groceries.

During strength training, you should do different exercises to work all the major muscle groups of your body (legs, hips, back, chest, abdomen, shoulders, and arms). You should try to do muscle-strengthening activities on two or more days each week. Allow one day in between sessions to avoid too much stress on your muscles and joints.

Will I bulk up too much if I do weightlifting or strength training?

Many women do not do any type of muscle-strengthening exercise because they are afraid of becoming too muscular. But women’s bodies are different from men’s bodies. Women naturally have more body fat and less muscle. Unless you are a professional bodybuilder or athlete, it is very unlikely that you would become more muscular or bulky than you would like from strength training.

Strength training or weightlifting is very healthy for most women.

Many women wonder whether it is OK to work out during their period. The answer is easy: Yes! In fact, you may find that you can be more physically active and at a greater intensity at certain times of the month than at other times.

Does my energy level change during my period?

It might. Some women report low energy levels during their period, while other women have more energy than usual during this time. Changing hormone levels through the menstrual cycle may be the cause.

Week 1: On the first day of your period, estrogen and progesterone levels are at their lowest. But they begin a gradual rise during your period. It may be easier to get active than in the previous weeks.

Week 2: In the week after your period ends, your energy levels might begin to go up. Estrogen levels begin rising quickly in preparation for ovulation (releasing an egg from the ovary).

Week 3: Estrogen levels peak around the time of ovulation, about two weeks before the next period for most women. When estrogen levels fall quickly after ovulation and progesterone levels begin rising, you may feel more tired or sluggish than usual. This does not mean that you should not exercise. In fact, being active might help boost your mood and give you more energy. Try exercising first thing in the morning, before your energy level goes down as the day goes on.

Week 4: In the week before your next period, you may feel less energy as both estrogen and progesterone levels are falling (if you are not pregnant). Physical activity may help premenstrual symptoms (PMS) get better even if your energy levels are low.

Try keeping a fitness journal to track your menstrual cycle and your energy levels during each workout. After a few months, you should be able to see when you have more or less energy during your cycle.

If you take hormonal birth control, like the pill, patch, shot, or vaginal ring, your energy levels may still go up and down with your cycle, but the differences may not be as noticeable.

Does my menstrual cycle affect my ability to exercise?

No. Researchers have not been able to find any differences during the menstrual cycle in a woman’s ability to exercise. The only significant finding was for endurance events, or long sports events, like marathons. In endurance events, women who had already ovulated but not started their period yet had a harder time exercising during hot and humid weather.

Can exercise help menstrual cramps?

Maybe. Researchers have found that some women have fewer painful cramps during menstruation if they exercise regularly. There are over-the-counter medicines for menstrual cramps or pain that work well with very few risks. There are almost no risks to regular physical activity, like walking, which may also help you feel better during your period.

What if I’m working out a lot and I don’t get my period?

Exercising too much can cause missed menstrual periods or make your periods stop entirely. Irregular or missed periods are more common in athletes and other women who train hard regularly. But if you haven’t worked out in a long time and suddenly start a vigorous fitness routine, your period could stop or become irregular.

Talk to your doctor or nurse if you have irregular or missed periods. A regular period is a sign of good health. These period problems can lead to more serious health problems, including problems getting pregnant and loss of bone density.

Are you exercising too much? Eating too little? Have your menstrual periods stopped or become irregular? If so, you may be putting yourself at high risk for several serious problems that could affect your health, your ability to remain active, and your risk for injuries. You also may be putting yourself at risk for developing osteoporosis, a disease in which bone density is decreased, leaving your bones vulnerable to fracture (breaking).

Why is missing my period such a big deal?

Some athletes see amenorrhea (the absence of menstrual periods) as a sign of successful training. Others see it as a great answer to a monthly inconvenience. And some young women accept it blindly, not stopping to think of the consequences. But missing your periods is often a sign of decreased estrogen levels. And lower estrogen levels can lead to osteoporosis, a disease in which your bones become brittle and more likely to break.

Usually, bones don’t become brittle and break until women are much older. But some young women, especially those who exercise so much that their periods stop, develop brittle bones and may start to have fractures at a very early age. Some 20-year-old female athletes have been said to have the bones of an 80-year-old woman. Even if bones don’t break when you’re young, low estrogen levels during the peak years of bone-building, the preteen and teen years, can affect bone density for the rest of your life. And studies show that bone growth lost during these years may never be regained.

Broken bones don’t just hurt – they can cause lasting physical malformations. Have you noticed that some older women and men have stooped postures? This is not a normal sign of aging. Fractures from osteoporosis have left their spines permanently altered.

Overtraining can cause other problems besides missed periods. If you don’t take in enough calcium and vitamin D (among other nutrients), bone loss may result. This may lead to decreased athletic performance, decreased ability to exercise or train at desired levels of intensity or duration, and increased risk of injury.

Who is at risk for these problems?

Girls and women who engage in rigorous exercise regimens or who try to lose weight by restricting their eating are at risk for these health problems. They may include serious athletes, “gym rats” (who spend considerable time and energy working out), and girls and women who believe "you can never be too thin."

“I was training really hard – all the time. Finally, my parents made me quit the cross country team…I was eating almost nothing, training with a stress fracture…I trained even when my body ached. I thought the pain, the headaches, and the missed menstrual periods were normal. I thought that was how a ‘champion’ was supposed to feel and train. I was proud of myself for being so thin and disciplined, and losing all the ‘baby fat’ I had carried throughout junior high school. My friends all said, “Gosh, you have lost so much weight!” But I wasn’t in control. After my parents made me quit the team and took me to get help, I realized that my training regimen was not normal or healthy. I realized that I was hurting myself, and that I did not have to be obsessive about my weight, eating habits, and exercise in order to be attractive. I still exercise now, and I watch what I eat, but I am much more relaxed, healthier (my doctor says!), and happier. I have more energy – and more fun. I don’t have to set any records anymore, and I am a champion anyway!”

—An athlete who recovered from problems associated with overtraining and missed periods.

How can I tell if someone I know, train with, or coach may be at risk for bone loss, fracture, and other health problems?

Here are some signs to look for:

• Missed or irregular menstrual periods.
• Extreme or “unhealthy-looking” thinness.
• Extreme or rapid weight loss.
• Behaviors that reflect frequent dieting, such as eating very little, not eating in front of others, trips to the bathroom following meals, preoccupation with thinness or weight, focus on low-calorie and diet foods, possible increase in the consumption of water and other no- and low-calorie foods and beverages, possible increase in gum chewing, limiting diet to one food group, or eliminating a food group.
• Frequent intense bouts of exercise (e.g., taking an aerobics class, then running 5 miles, then swimming for an hour, followed by weight-lifting).
• An “I can’t miss a day of exercise/practice” attitude.
• An overly anxious preoccupation with an injury.
• Exercising despite illness, inclement weather, injury, and other conditions that might lead someone else to take the day off.
• An unusual amount of self-criticism or self-dissatisfaction.
• Indications of significant psychological or physical stress, including: depression, anxiety or nervousness, inability to concentrate, low levels of self-esteem, feeling cold all the time, problems sleeping, fatigue, injuries, and constantly talking about weight.

How can I make needed changes to improve my bone health?

If you recognize some of these signs in yourself, the best thing you can do is to make your diet more healthful. That includes consuming enough calories to support your activity level. If you’ve missed periods, it’s best to check with a doctor to make sure it’s not a sign of some other problem and to get his or her help as you work toward a healthier balance of food and exercise. Also, a doctor can help you take steps to protect your bones from further damage.

What can I do if I suspect a friend may have some of these signs?

First, be supportive. Approach your friend or teammate carefully, and be sensitive. She probably won’t appreciate a lecture about how she should be taking better care of herself. But maybe you could share a copy of this fact sheet with her or suggest that she talk to a trainer, coach, or doctor about the symptoms she’s experiencing.

My friend drinks a lot of diet sodas. She says this helps keep her trim.

Girls and women who may be dieting often drink diet sodas rather than milk. Yet, milk and other dairy products are a good source of calcium, an essential ingredient for healthy bones. Drinking sodas instead of milk can be a problem, especially during the teen years when rapid bone growth occurs. If you (or your friend) find yourself drinking a lot of sodas, try drinking half as many sodas each day, and gradually add more milk and dairy products to your diet. A frozen yogurt shake can be an occasional low-fat, tasty treat. Or try a fruit smoothie made with frozen yogurt, fruit, or calcium-enriched orange juice.

For fitness instructors and trainers

It’s important for you to be aware of problems associated with bone loss in today’s active young women. As an instructor or trainer, you are the one who sees, leads, and perhaps even evaluates the training sessions and performances of your clients. You may know best when something seems to be amiss. You also may be the best person to help a zealous female exerciser recognize that she is putting herself at risk for bone loss and other health problems and that she should establish new goals.

Trainers and instructors also should be aware of the implicit or explicit messages they send. Health, strength, and fitness should be emphasized, rather than thinness. Use caution when advising female clients to lose weight. And, if such a recommendation is deemed necessary, knowledgeable personnel should offer education and assistance about proper and safe weight management. As an instructor or trainer, it’s best to maintain a professional rapport with your clients, so they can feel comfortable approaching you with concerns about their exercise training programs, appropriate exercise goals and timelines, body image and nutrition issues, as well as more personal problems regarding eating practices and menstruation.

My coach and I think I should lose just a little more weight. I want to excel at my sport!

Years ago, it was not unusual for coaches to encourage athletes to be as thin as possible for many sports (e.g., dancing, gymnastics, figure skating, swimming, diving, and running). However, many coaches now realize that being too thin is unhealthy and can negatively affect performance. It’s important to exercise and watch what you eat. However, it’s also important to develop and maintain healthy bones and bodies. Without these, it will not matter how fast you can run, how thin you are, or how long you exercise each day. Balance is the key!

I’m still not convinced. If my bones become brittle, so what? What’s the worst thing that could happen to me?

Brittle bones may not sound as scary as a fatal or rare disease. The fact is that osteoporosis can lead to fractures. It can cause disability.

Imagine having so many spine fractures that you’ve lost inches in height and walk bent over. Imagine looking down at the ground everywhere you go because you can’t straighten your back. Imagine not being able to find clothes that fit you. Imagine having difficulty breathing and eating because your lungs and stomach are compressed into a smaller space. Imagine having difficulty walking, let alone exercising, because of pain and misshapen bones. Imagine constantly having to be aware of what you are doing and having to do things so slowly and carefully because of a very real fear and dread of a fracture – a fracture that could lead to a drastic change in your life, including pain, loss of independence, loss of mobility, loss of freedom, and more.

Osteoporosis isn’t just an "older person’s" disease. Young women also experience fractures. Imagine being sidelined because of a broken bone and not being able to get those good feelings you get from regular activity.

Eating for healthy bones

How much calcium do I need? It’s very important to your bone health that you receive adequate daily amounts of calcium, vitamin D, phosphorus, and magnesium. These vitamins and minerals are the most influential in building bones and teeth. This chart will help you decide how much calcium you need.

Recommended calcium intakes (mg/day)

Where can I get calcium and vitamin D? Dairy products are the primary food sources of calcium. Choose low-fat milk, yogurt, cheeses, ice cream, or products made or served with these choices to fulfill your daily requirement. Three servings of dairy products per day should give you at least 900 mg (milligrams) of calcium. Green vegetables are another source. A cup of broccoli, for example, has about 136 mg of calcium.

Milk and dairy products. Many great snack and meal items contain calcium. With a little planning and "know-how," you can make meals and snacks calcium-rich!

• Milk. Wouldn’t a tall, cold glass of this refreshing thirst quencher be great right now? If you’re concerned about fat and calories, choose reduced-fat or fat-free milk. You can drink it plain or with a low- or no-fat syrup or flavoring, such as chocolate syrup, vanilla extract, hazelnut flavoring, or cinnamon.
• Cheese. Again, you can choose the low- or no-fat varieties. Use all different types of cheese for sandwiches, bagels, omelets, vegetable dishes, pasta creations, or as a snack by itself!
• Pudding (prepared with milk). You can now purchase (or make from a mix) pudding in a variety of flavors with little or no fat, such as chocolate fudge, lemon, butterscotch, vanilla, and pistachio. Try them all!
• Yogurt. Add fruit. Eat it plain. Add a low- or no-fat sauce or syrup. No matter how you choose to eat this calcium-rich food, yogurt remains a quick, easy, and convenient choice. It’s also available in a variety of flavors. Try mocha-fudge-peppermint-swirl if you’re more adventurous at heart and vanilla if you’re a more traditional yogurt snacker!
• Frozen yogurt (or fat-free ice cream). Everybody loves ice cream. And now, without the unnecessary fat, you can enjoy it more often! Mix yogurt, milk, and fruit to create a breakfast shake. Have a cone at lunchtime or as a snack. A scoop or two after dinner can be cool and refreshing.

What are other sources of calcium? Many foods you already buy and eat may be "calcium fortified." Try calcium-fortified orange juice or calcium-fortified cereal. Check food labels to see if some of your other favorite foods may be good sources of calcium. You also can take calcium supplements if you think you may not be getting enough from your diet.

Are you thinking about exercising to lose weight? First, find out if you need to lose weight. Your doctor can help you figure out what weight is right for you. You also can learn more about healthy weight ranges from our body mass index (BMI) info. If you do need to lose weight, your doctor can help with advice on how to do it. (You can learn more about working with doctors, including getting help paying for appointments.)

Being physically active definitely is a smart move if you're trying to reach a healthy weight and stay there. Plus, being active has lots of other benefits too!

Weight loss success

If you need to lose weight, make sure to set realistic goals and start with small steps. If you aim for a goal you can't reach, you may feel annoyed, weak, or disappointed. That really won't help!

It's a good idea to avoid:

• Trying to lose weight very fast (like in time for a certain party)
• Deciding you want to weigh as much as someone you know (because every body is different)
• Hoping to look like models (since some of them are a very unhealthy weight or their pictures are changed to make them look thinner)
• Following extreme diets and exercise plans that can hurt your body and make you frustrated
• Being hard on yourself if you miss a workout or eat something unhealthy

Two of the main things that affect whether or not you lose weight include:

• How active you are. To lose weight, you need to "burn" (use) more calories than you take in from foods and drinks. Physical activity helps you burn calories.
• How much and what kinds of food you eat. Some foods, like fruits and veggies, have fewer calories than other foods, like cookies and cakes. (And they are healthier too!) Visit our section on nutrition to learn what kinds of foods to eat and how much food you need to stay healthy.

If you think you may need to lose weight, your best bet is to make healthy habits part of your everyday life. Here are some tips:

• Talk to a doctor or nurse about a healthy weight goal. Work together to set weight-loss goals that are right for you. You might ask about this during your regular checkup.
• Try following a healthy eating and exercise plan. A doctor, nurse, nutritionist, or dietitian can help you make a healthy eating plan. Aim to lose weight slowly and steadily (about 1 to 2 pounds per week).
• Think about whether you eat when you're sad or worried. You can find other ways to cope with these feelings. Visit our section on your feelings, or talk with a friend or trusted adult.

Physical activity is important for all women throughout their lives. Read on for ways you can change your physical activity routine to fit your needs based on your age, stage of life, or physical abilities.

Physical activity for every woman

Regular physical activity benefits your health. Any physical activity is better than no physical activity. The Physical Activity Guidelines can help you plan how much physical activity to do each week. Talk to your doctor or nurse about how to fit physical activity into your life.

Physical activity for larger women

Carrying extra weight can make moving around much more difficult.

If you have overweight or obesity and you want to begin exercising, start slowly by moving more around your home. Try doing stretches or lifting weights while watching TV. You can lift cans of food, jugs of water, or other household items as weights.

Walking in a safe place near where you live is a great way to begin getting more exercise or physical activity for women of any age or shape. You don’t need special clothes or sports equipment, just comfortable walking shoes. Start with 10-minute walks at a comfortable pace (you can still breathe normally and talk while walking) at least three days a week. Add more minutes of walking and increase how fast you walk as your body gets used to the activity.

Here are some tips to get you started:

• Get moving at home. You don’t have to leave your house to be active. Try a free on-demand workout video, a free online workout video, or a DVD from your local library.
• Choose activities like swimming or riding a stationary bikeif your feet or joints hurt when you stand. These activities put less stress on your joints because your legs are not supporting the weight of your body. Ask your doctor or nurse for help in coming up with a physical activity plan that is right for you.
• Physical activity does not have to be hard or boring to be good for you. Anything that gets you moving — even for only a few minutes a day — is a great start. Being physically active on a regular basis can make a big difference in your health.

Physical activity for older women

As you get older, it’s important to stay active. Regular physical activity can help keep you healthy and strong. Physical activity offers many benefits for older women:

• Preventing muscle and bone loss
• Reducing the risk of falling and breaking bones
• Helping prevent or delay conditions like diabetes and heart disease
• Reducing the joint swelling and pain of arthritis
• Reducing symptoms of anxiety and depression
• Helping make you feel good and enjoy life more
• Helping you stay independent longer

All women of all ages, shapes, and abilities should get at least 2 hours and 30 minutes each week of moderate-intensity aerobic physical activity. You also need muscle-strengthening activities on at least two days each week.

Balance exercises are important for all women, but especially older women who are at a higher risk of falls. This includes women who have had falls in the recent past or have trouble walking. Researchers know that doing balance and muscle-strengthening activities for at least 1 hour and 30 minutes a week helps lower the chance that you will fall down and hurt yourself. Examples of these exercises include tai chi, walking backward, and standing from a sitting position.

Getting active can help you live a longer, healthier life.

Physical activity for women with disabilities

A disability may make it harder to stay active, but there are still many ways to be physically active. There are also many reasons why being physically active is important if you have a disability.

Physical activity helps with flexibility, mobility, and coordination. Getting regular physical activity can also help you stay independent by preventing health problems, such as heart disease, that can make it harder for you to take care of yourself.

Benefits of physical activity for women with disabilities include:

• Helping lower the risk of heart disease, high blood pressure, colon cancer, and diabetes
• Helping improve your endurance and muscle strength, including toning muscles you may use less often because of your disability
• Reducing symptoms of anxiety and depression
• Reducing the joint swelling and pain of arthritis

Women with disabilities should try to get the same amount of physical activity as all adults. That means getting at least 2 hours and 30 minutes each week of moderate-intensity aerobic physical activity and two or more days each week of muscle-strengthening activities.

Before you start, talk to your doctor, physical therapist, or exercise specialist about how you can modify physical activity to accommodate your disability.

If you're active, you need fuel. But how much do you need, and when? Keep reading to learn more.

• Foods for working out
• What to drink during physical activity
• What about sports drinks, energy drinks, and vitamin waters?

Foods for working out

Everybody needs to eat a variety of healthy foods. But you may need to eat more if you are very active, like if you run several days each week or are on a sports team. That's because you need food to grow and to fuel all your activity. If you are very active but don't eat enough healthy food, your body may slow down and not work as well.

Confused about how much you need to eat? Use the MyPlate Checklist Calculator to find a personalized eating plan. You can look at the eating plans with a parent or guardian. In addition, you can get nutrition help from people like a doctor, school nurse, and nutritionist or dietitian. A coach or trainer also might be able to help. And you can learn more about healthy eating in our Nutrition section.

Wondering when to eat? Try not to eat a meal right before exercising, or you could get a stomach ache. It can take a few hours to digest a big meal. After a smaller meal, waiting around an hour should be fine. If you have several athletic events in one day (such as a few tennis matches), you can eat small snacks between events.

What about bars? Energy bars can give you energy. But they can also give you hundreds of extra calories. (One bar can have as many calories as a small order of fries!) That may be fine for teens who often do things that burn a lot of calories, like going on long runs or playing on the soccer team. For some teens, though, energy bars may pack on too many pounds. Instead, try other on-the-go snacks, like air-popped popcorn, whole-grain cereal, a banana, low-fat cheese sticks, or unsalted nuts.

What to drink during physical activity

If you are active, you need to make sure to get enough water and other fluids. Getting too little fluids can mess up your memory, concentration, athletic ability, and more. Check out some helpful tips below.

Water works! It does a great job of replacing fluids you lose when you sweat, for example. How much do you need? That depends on lots of things, including how active you are and how hot it is.

Experts suggest drinking about a cup of water an hour or two before getting active. During your activity, try to drink around a cup every 15 or 20 minutes. Keep drinking water after the activity ends and sipping throughout the day.

You may need to drink even more if you are going to be working out very hard, such as in something like competitive soccer or cross-country running. You can ask your doctor, coach, or trainer for more information.

One way to tell if you're getting enough water is to check your urine (pee). It should be light yellow. If it's dark yellow, you probably need more water.

Don't wait until you feel thirsty. If you feel thirsty, you could be getting dehydrated. Being dehydrated means that your body does not have as much fluid as it should. It can be dangerous. Signs of dehydration include:

• A dry or sticky mouth
• Having less or darker urine
• Fast heart rate
• Feeling irritable or confused
• Feeling dizzy or weak
• Having a headache

If you have any of the symptoms above, tell an adult.

What about sports drinks, energy drinks, and vitamin waters?

Usually, water is all you need when you are active.

Sports drinks can help athletes when they are active for more than an hour doing an intense activity, such as running, biking, or playing basketball or soccer. That's because sports drinks (such as Gatorade) have sugars and salts you lose when you work out. If you don't exercise that much, it's best to avoid sports drinks because they have extra sugar and calories that may lead to cavities and weight gain.

Energy drinks are a bad idea for teens. For one, energy drinks often have a lot of caffeine. In fact, one energy drink could have as much caffeine as 14 cans of soda. What's wrong with caffeine? It can cause problems like increased blood pressure, trouble sleeping, and feeling nervous. It's also possible caffeine may block your body's use of calcium (which you need for strong bones). Plus, energy drinks can have things that are not good for your health, like lots of added sugar.

Vitamin waters or enhanced waters have extra vitamins and minerals. They may also be packed with extra calories, artificial sweeteners, caffeine, or ingredients that may not be safe for kids. The best way for you to get the nutrients you need is by eating a wide variety of healthy foods.

Wondering what to wear when you work out? Well, lots of activities don't require any special clothes. Sometimes, your clothes do matter. (And we don't mean how cool they look! Anybody who is working out looks cool, we say!)

Choosing workout clothes

When picking a workout outfit, remember:

• Don't wear clothes that are very tight. You need to be able to move freely. And if you want to stay cool, air needs to reach your skin so it can dry your sweat.
• Color matters (really). In the summer, lighter colors will help you keep cooler. In the winter, dark clothes trap light and help you stay warm.
• Wear layers when it is cold out. You can take some off as you warm up.
• The right stuff. Don't forget about safety! Wearing the right equipment can help keep you safe when you're playing sports or being active. Read more about equipment and staying safe.
• Think about your head. Wear a hat or cap for sun protection. In cold weather, wear wool or ski caps to stay warm.
• Find the right fabric. If you are going to sweat, you may be more comfortable in material that soaks up wetness. Try a synthetic, like polypropylene (say: pol-ee-PROH-puh-leen). Cotton may be less comfortable because it stays wet longer.
• Consider wearing a comfortable sports bra. Wearing a supportive sports bra can help protect your breasts and keep them from bouncing painfully while exercising. Try on a few to see which style you prefer. If you need help finding the right fit, ask for help in a department store or bra store.

How to pick the right workout shoes

Wearing the right shoes when you work out is very important. To find the right pair, follow these tips:

• Make sure your shoes protect your feet. They should be sturdy and have cushioned soles. They should also have arch supports (the raised part inside that curves under the bottom of your foot).
• Make sure the shoe is right for what you do. If you plan to run or play a certain sport a lot, consider shoes made for that activity. Tennis players should wear tennis shoes and runners should wear running shoes, for example. Ask a sports shoe salesperson for help.
• Get the right fit. Ask a salesperson to measure your foot and then to check the fit. The wrong fit can hurt or even cause foot problems. Try to shop at the end of the day when your feet are a little larger (just like they are when you exercise). Also, when trying on shoes, wear the kind of socks you wear to work out.

Physical activity has many benefits for your health. But staying safe during physical activity is just as important for your health. Start slow if you have not been physically active for a while. This will help you stick with it and avoid injury.

Should I talk to my doctor before starting a physical activity program?

Maybe. Most healthy women do not need to talk to their doctor or nurse before becoming active. But if you have health concerns or have not worked out in a while, it is a good idea to talk to a doctor or nurse about the types of physical activity that are right for you.

This is especially important if you:

• Have or are at high risk of heart disease
• Have had or are at high risk of a stroke
• Have or are at high risk of diabetes
• Have obesity (body mass index of 30 or greater)
• Have an injury
• Are pregnant

Are women more at risk than men are for injuries during physical activity?

Yes and no. Both women and men are at risk for injuries during physical activity. The degree of risk depends on the type of activity. For example, contact sports carry more of a risk than activities like walking.

But women are more likely than men to develop “runner’s knee” during physical activity. This condition may happen when the shock-absorbing tissue (called cartilage) in the knee wears down or when there are problems with the alignment of the bones, tendons, and muscles of the knee. It can happen because of many sports or activities, not just running.

Women are three times more likely to have an anterior cruciate ligament (ACL) tear than men are. The ACL holds the knee in place.

Reasons for the difference in injury may include the following:

• Women’s anatomies (body structure) are different from men. Women have smaller, weaker muscles supporting the knee.
• Women and men land differently when running or jumping. Women and men also move in different ways during physical activity because of differences in the shape of the hips, muscle strength, and leg alignment. This puts women more at risk for injury during activities that include jumping, twisting, and turning, such as skiing, basketball, and tennis.
• Changing hormones during the menstrual cycle or pregnancy may loosen and weaken joints.

You may benefit from exercises you can do to strengthen your knee joint and lower the chance for ACL injuries. Talk to your doctor or nurse about your risk and what you can do to prevent injury.

How can I help prevent an injury?

You can take the following steps to help prevent an injury:

• Use safety equipment. For example, wear a helmet for bike riding or supportive shoes for walking or jogging.
• Warm up to your workout. Spend five to 10 minutes doing a “light” version of your workout. For example, if you’re taking a brisk walk, walk slowly or march in place. If you’re biking, keep it slow before building your speed. Slow down again after working out until your heart rate returns to normal.
• Drink plenty of fluids when you are physically active, even if you are not thirsty.
• Always bend forward from the hips, not the waist. For most types of exercise, if you keep your back straight, you’re probably bending the right way. If your back “humps,” that’s probably wrong. Talk to an exercise trainer or physical therapist if you have questions or concerns.
• Stop being active if you feel very out of breath, dizzy, or nauseated or have pain. If your chest feels tight or painful or you feel faint or have trouble breathing, stop the activity right away. Always call 911, or have someone call for you, if you lose consciousness, cannot breathe, have uncontrollable bleeding, or have a serious injury like a broken bone. Talk to your doctor or nurse if you regularly have trouble exercising because you get dizzy or nauseated, cannot breathe well, or have pain during or after exercise.

You will probably feel some soreness or discomfort when starting any physical activity. But in many ways, being active will probably make you feel better. If you do have pain that continues for days after an activity, talk to your doctor or nurse.

Is there an athlete inside you waiting to get out? You can read about the topics below. (And remember, if sports aren't your thing, there are lots of other ways to be active!)

Why choose sports?

Playing sports can help you make friends, boost your mood, and teach you tons of skills. Girls who play sports may:

• Have greater self-esteem and less depression
• Learn how to set goals and work hard
• Have a more positive body image
• Learn about working as part of a team
• Do better in school

Picking a sport

It helps to think about a few issues when choosing a sport. Start by asking yourself some questions:

• Do you like to work together with teammates, the way you do in soccer or lacrosse?
• Do you prefer to work more on your own, as in swimming or track?
• How do you feel about competition? Does it twist your tummy? Maybe inviting a friend to shoot hoops or go hiking is more for you.
• Do you like to keep moving? Does soccer, basketball, or field hockey sound fun to you?
• Do you like music? You might think about dance and cheerleading, which can offer great workouts.
• Are you interested in relaxing and connecting your mind and body, like you do in yoga or Pilates?

Safety in sports

Stay in the game with these tips:

• If you're new to a sport, work your way up slowly.
• Before you start a sport, see your doctor for a sports physical. Some states require these examinations to make sure you are healthy enough to play. But even if a sports physical is not required, it makes good sense to get one.
• Follow safety rules for your sport. In cheerleading, for example, don't practice on hard, wet, or uneven surfaces, and don't create pyramids that are more than two people high. And learn what to do in case of an injury or emergency.
• Talk to your coach about any safety concerns, or ask your parent or guardian to talk to your coach.
• Learn how to help your teammates stay safe. For sports like cheerleading or gymnastics, for example, learn how to be a good spotter.
• Make sure to read about concussions. Anyone who might have a head injury should not practice or compete until a health professional says it's safe.
• Give your body a break. Experts suggest the following:
  • Take at least one day off per week from your sport or training schedule.
  • Take at least two to three months off from your sport each year.
  • If you train a lot in a high-impact sport, such as running, try replacing some intense training with lower-impact activities, such as biking.
• Try different sports. Playing the same sport over and over can put repeated stress on certain parts of your body. Doing a mix of sports and activities can help prevent this problem.
• Strengthen your muscles. Conditioning exercises, such as sit-ups and push-ups, can strengthen the muscles you use when you compete. Learn more about strengthening exercises.
• Skip special supplements. Products may claim to help you lose weight, bulk up, or improve your performance. Often these don't work, and they can even hurt you. Remember, all you really need to succeed is good nutrition.

Between work, school, errands, volunteering, and family commitments, finding time for physical activity can be challenging. If that describes you, remember that some movement is better than none! Even small bouts of physical activity provide some health benefits.

Walking more is an easy way for most people to add physical activity to their day. Try these tips and see how fast the minutes add up.

• Instead of sitting and waiting while your child is at sports practice, walk around the field.
• Walk your dog a little farther than you normally do.
• Find a convenient path near your home or work. Set specific times to walk there and walk to routine destinations.
• Host a virtual walking meeting. Walk and talk over work problems with your co-workers for the first 20 minutes.
• Make a walking date with a friend or family member. Skip the flavored coffee and do a loop around a park or the neighborhood instead.
• Take a walking lunch break. Keep walking shoes and socks in your car or filing cabinet.
• If you normally walk outside but the weather is bad, head to the local mall for a climate-controlled walk.
• Stop circling parking lots looking for a close spot. Park further away and walk briskly to your destination. You could get a few more minutes of physical activity by walking around the entire parking lot before going inside.
• At airports, walk to your concourse instead of taking a shuttle or tram.

Getting Started

Start slowly and work up to being physically active 150 minutes a week. You might split that into 30 minutes a day, 5 days a week. See examples of weekly physical activity schedules for adults and come up with a plan that works for you. Using a physical activity diary might help.

Eventually, you will want to walk at a moderate intensity pace. That means you’ve raised your heart rate and broken a sweat. In general, at moderate intensity, you can talk, but you can’t sing.

Finding time to be consistently physically active is one of the most important things you can do to improve your health. Being physically active can help you feel better immediately, and regular physical activity can reduce the risk of many chronic diseases, including heart disease and some cancers. Start with a few extra minutes of physical activity today, then add a few more minutes tomorrow, and soon you’ll reach the goal of 150 minutes a week.

Trying to get more physically active? You don’t have to go it alone. How about working out with a little help from your friends? You and your workout buddy can cheer each other on.

When you work out with a partner, you’re likely to:

1. Feel more motivated. When you and your buddy encourage each other, you’ll work harder (and get better results!). And there’s nothing wrong with a little friendly competition.
2. Be more adventurous. It’s easier to try new things with a buddy. You may just find an activity you love, one that feels more like fun and less like a workout.
3. Be more consistent. When someone else is counting on you to show up, you won’t want to let them down.

To enjoy all those benefits, you’ll need the right workout buddy. Look for someone with the same goals, schedule, and commitment you have. Someone who makes you feel positive and inspires you to hit the trail or treadmill on a regular basis.

How do you find the right fit? Talk to friends, co-workers, neighbors, people at the gym. Or find a buddy closer to home: What about a hike with your dog, who thinks every walk is the best walk ever? Now quality time is also fitness time. Good move! You could also try a workout app to connect with friends and others that share your goals and can help keep you motivated.

Even if you like to work out alone, changing things up with a buddy every once in a while can help you work out harder and learn new things. You can always switch back to solo workouts any time.