Rewards and Benefits
You should try to exercise at a moderate level for at least 60 minutes most days of the week. In addition to being active everyday, it is recommended that you spend 20 to 30 minutes of your exercise time doing vigorous aerobic activity at least 3 times a week. Starting slow and building up to this is just fine. Every little bit counts when you're just beginning, so take time for a short walk or bike ride a few times during the day. It is important to pay attention to how your body feels, such as getting really tired, out of breath or being too sore the next day. If you are unsure, ask your health care provider, coach, physical education teacher, or school nurse. Always, drink water before, during and after exercise.
Here are some of the reasons why exercise is so important:
- Exercise benefits every part of the body, including the mind. Exercising causes the body to produce endorphins, chemicals that can help a person to feel more peaceful and happy. Exercise can help some people sleep better. It can also help some people who have mild depression and low self-esteem. Plus, exercise can give people a real sense of accomplishment and pride at having achieved a certain goal -- like beating an old time in the 100-meter dash.
- Exercising can help you look better. People who exercise burn more calories and look more toned than those who don't. In fact, exercise is one of the most important parts of keeping your body at a healthy weight.
- Exercise helps people lose weight and lower the risk of some diseases. Exercising to maintain a healthy weight decreases a person's risk of developing certain diseases, including type 2 diabetes and high blood pressure. These diseases, which used to be found mostly in adults, are becoming more common in teens.
- Exercise can help a person age well. This may not seem important now, but your body will thank you later. Women are especially prone to a condition called osteoporosis (a weakening of the bones) as they get older. Studies have found that weight-bearing exercise, like jumping, running or brisk walking, can help girls (and guys!) keep their bones strong.
There are three components to a well-balanced exercise routine: aerobic exercise, strength training, and flexibility training.
What does it mean to be physically "fit?"
Physical fitness is defined as "a set of attributes that people have or achieve that relates to the ability to perform physical activity." In other words, it is more than being able to run a long distance or lift a lot of weight at the gym. Being fit is not defined only by what kind of activity you do, how long you do it, or at what level of intensity. While these are important measures of fitness, they only address single areas. Overall fitness is made up of five main components:
- Cardio respiratory endurance
- Muscular strength
- Muscular endurance
- Body composition
In order to assess your level of fitness, look at all five components together.
What is "cardio respiratory endurance (cardio respiratory fitness)?"
Cardio respiratory endurance is the ability of the body's circulatory and respiratory systems to supply fuel during sustained physical activity. To improve your cardio respiratory endurance, try activities that keep your heart rate elevated at a safe level for a sustained length of time such as walking, swimming, or bicycling. The activity you choose does not have to be strenuous to improve your cardio respiratory endurance. Start slowly with an activity you enjoy, and gradually work up to a more intense pace.
What is "muscular strength?"
Muscular strength is the ability of the muscle to exert force during an activity (USDHHS, 1996 as adapted from Wilmore & Costill, 1994). The key to making your muscles stronger is working them against resistance, whether that is from weights or gravity. If you want to gain muscle strength, try exercises such as lifting weights or rapidly taking the stairs.
What is "muscular endurance?"
Muscular endurance is the ability of the muscle to continue to perform without fatigue (USDHHS, 1996 as adapted from Wilmore & Costill, 1994). To improve your muscle endurance, try cardio respiratory activities such as walking, jogging, bicycling, or dancing.
What is "body composition?"
Body composition refers to the relative amount of muscle, fat, bone, and other vital parts of the body. A person's total body weight (what you see on the bathroom scale) may not change over time. But the bathroom scale does not assess how much of that body weight is fat tissue and how much is lean mass (muscle, bone, tendons, and ligaments). Body composition is important to consider for health and managing your weight!
Body Mass Index
Body Mass Index (BMI) is a number calculated from a person's weight and height. BMI does not measure body fat directly, but research has shown that BMI correlates to direct measures of body fat. BMI can be considered an alternative for direct measures of body fat. Additionally, BMI is an inexpensive and easy-to-perform method of screening for weight categories that may lead to health problems.
For children and teens, BMI is age- and sex-specific and is often referred to as BMI-for-age percentile.
How is BMI used with children and teens?
BMI is used as a screening tool to identify possible weight problems for children. CDC and the American Academy of Pediatrics (AAP) recommend the use of BMI to screen for overweight in children beginning at 2 years old.
For children, BMI is used to screen for overweight, at risk of overweight, or underweight. However, BMI is not a diagnostic tool. For example, a child may have a high BMI for age and sex, but to determine if excess fat is a problem, a health care provider would need to perform further assessments. These assessments might include skinfold thickness measurements, evaluations of diet, physical activity, family history, and other appropriate health screenings.
What is "flexibility?"
Flexibility is the range of motion around a joint. Good flexibility in the joints can help prevent injuries through all stages of life. If you want to improve your flexibility, try activities that lengthen the muscles such as swimming or a basic stretching program.
What's Right for Me?
One of the biggest reasons people drop an exercise program is lack of interest: If what you're doing isn't fun, it's hard to keep it up. The good news is that there are tons of different sports and activities that you can try out to see which one inspires you.
When picking the right type of exercise, it can help to consider your workout personality. For example, do you like to work out alone and on your own schedule? If so, solo sports like biking or snowboarding may be for you. Or do you like the shared motivation and companionship that comes from being part of a team?
You also need to plan around practical considerations, such as whether your chosen activity is affordable and available to you. (Activities like horseback riding may be harder for people who live in cities, for example.) You'll also want to think about how much time you can set aside for your sport.
It's a good idea to talk to someone who understands the exercise, like a coach or fitness expert at a gym. He or she can get you started on a program that's right for you and your level of fitness.
Another thing to consider is whether any health conditions may affect how -- and how much -- you exercise. Doctors know that most people benefit from regular exercise, even those with disabilities or conditions like asthma. But if you have a health problem or other considerations (like being overweight or very out of shape), talk to your doctor before beginning an exercise plan. That way you can get information on what exercise programs are best and what to avoid.
Too Much of a Good Thing
As with all good things, it's possible to overdo exercise. Although exercising is a great way to maintain a healthy weight, exercising too much to lose weight isn't healthy. The body needs enough calories to function properly. This is especially true for teens, who are still growing.
Exercising too much in an effort to burn calories and lose weight (also called compulsive exercise) can be a sign of an eating disorder. If you ever get the feeling that your exercise is in charge of you rather than the other way around, talk with your doctor, a parent, or another adult you trust.
For more information on the importance of physical activity go to www.cdc.gov.
It's also possible to over train -- something high school athletes need to watch out for. If you participate in one sport, experts recommend that you limit that activity to a maximum of 5 days a week, with at least 2-3 months off per year. You can still train more than that as long as it's cross training in a different sport (such as swimming or biking if you play football).
Participating in more than one activity or sport can help athletes use different skills and avoid injury. Also, never exercise through pain. And, if you have an injury, make sure you give yourself enough time to heal. Your body -- and your performance -- will thank you.
Considering the benefits to the heart, muscles, joints, and mind, it's easy to see why exercise is wise. And the great thing about exercise is that it's never too late to start. Even small things can count as exercise when you're starting out -- like taking a short bike ride, walking the dog, or raking leaves.
If you're already getting regular exercise now, try to keep it up after you graduate from high school. Staying fit is often one of the biggest challenges for people as they get busy with college and careers.