Key Messages:

• Regular physical activity not only helps lower your risk of cancer, but it may also improve quality of life, mood, and other side effects of cancer and cancer treatment for people with cancer and cancer survivors.
• Most people should aim for a minimum of 30 minutes of moderate physical activity on five or more days each week.
• An exercise program should be based on a person's age, fitness level, stage and type of cancer, and cancer treatment.
• Before starting a program, talk with your doctor to get suggestions on the types of exercises that are appropriate for you.

Here are some tips on increasing physical activity to prevent cancer or lower the risk of return of the cancer (in those with a history of cancer):

Defining activity level

Moderate and vigorous activities can be done in a variety of settings, including at home, outside, or in a recreational setting, like a gym.

Moderate activities. These activities require an effort similar to a brisk walk. A person should be able to talk, but would prefer not to. Many adults choose walking for moderate physical activity.

Vigorous activities. These activities, such as jogging, use large muscle groups and increase heart rate, breathing rate and frequency, and sweating.

People undergoing cancer treatment

Understandably, physical activity levels tend to decline after a cancer diagnosis and during treatment. For example, various studies show that women are significantly less physically active after a breast cancer diagnosis. And, the type of treatment a woman receives for breast cancer influences how often she exercises. Studies show that there is a greater decrease in sports activity among women treated with radiation therapy and chemotherapy (50% decrease) than women treated with surgery alone (24% decrease) or those treated only with radiation therapy (23% decrease).

However, high levels of exercise may help reduce the risk of death from breast cancer, and it may be appropriate for a person with or treated for breast cancer to follow an exercise schedule.

A "prescription" of exercise is often recommended for people with other types of cancer, including those with advanced disease, and survivors. The exercise program should be based on a person's age, fitness level, stage and type of cancer, and cancer treatment. Talk with your doctor or a member of your health care team to learn more and get suggestions for appropriate exercise plans.

Patients receiving treatment, such as chemotherapy or radiation therapy, may be too tired to do more than slow walking or stretching exercises. In general, patients undergoing cancer treatment should exercise at no greater than 50% to 60% of their maximum heart rate.

Cancer survivors

Being diagnosed with cancer and undergoing treatment for the disease may result in side effects that significantly affect a survivor's quality of life. Studies show that a 12-week to 16-week aerobic exercise program, ranging from supervised aerobic sessions in facilities to home-based walking programs, results in:

• Improved fitness
• Moderate weight and fat loss
• Increased lean mass
• Reduced fatigue
• Improved mood
• Improved overall quality of life

Most people who have completed treatment can start exercising more intensely and more often, although they may need to start slowly. People who were active before their cancer diagnosis should begin at a lower level than before their diagnosis. The American Cancer Society (ACS) recommends the following guidelines for participating in a physically active lifestyle:

• Adults should be moderately or vigorously active, in addition to other daily activities, for a minimum of 30 minutes on five or more days of the week; 45 to 60 minutes of activity is better.
• Children and adolescents should be moderately to vigorously active for at least 60 minutes a day, at least five days per week.
• Survivors should follow the same recommendations for exercise and cancer prevention as people who haven't had cancer, taking overall health and the ability to exercise into consideration.

Physical activity suggestions

Scientists estimate that as many as one-third of cancers of the colon, breast, and kidney can be attributed to obesity and a lack of enough physical activity. Exercise not only reduces the risk for cancer, but also the risk for other chronic diseases such as heart disease and diabetes. Although it isn't known how intensely, how long, and how frequently people need to exercise to reduce the risk of disease, following these physical activity recommendations from the U.S. Department of Health and Human Services and the U.S. Department of Agriculture are good places to start:

• Keep body mass index (BMI) between 18.5 and 25 (talk to your doctor to determine your BMI, a formula that indicates if your weight is in a healthy range).
• Avoid unnecessary weight gain.
• Participate in moderate to vigorous activity for a minimum of 30 minutes on five or more days each week; 45 minutes or more of moderate to vigorous activity on five or more days each week may further reduce risk for breast and colon cancers.
• Perform moderate to vigorous activity 60 minutes per day on most days of the week to maintain weight; and 60-minute to 90-minute sessions each day to maintain weight loss.
• Increase activity length and intensity by no more than 10% each week.
• Exercise for several shorter sessions if you don't have the time or energy for a longer session. The health benefits of several short, 10-minute segments are similar to a one longer session of exercise.
• If you are new to exercise, start slow and gradually increase your physical activity to 30 minutes of moderate to vigorous activity.

Tips for children and teens

Childhood activity levels may predict how active a person is as an adult. The ACS recommends that children and young adults get at least an hour of moderate to vigorous physical activity on five or more days of the week. This can be done by reducing the amount of time your children and teens watch television and use a computer and through participation in sports or fitness activities at school or home.

Most children and young adults can safely participate in moderate physical activity without first talking to a doctor, but those with cancer or being treated for cancer may want to talk with their health care team when planning an exercise program.

Suggestions for older adults

Increasing the level of physical activity at any age provides important health benefits. Regular physical activity can help reduce decline in body functions associated with aging, as well reduce the risk for a variety of diseases. Men older than 40, women older than 50, and people with chronic illnesses and/or who have any kind of heart problem should talk with their doctors about how to safely begin physical activity. If an older person has problems with exercise because of poor balance, frailty, pain, or the presence of disease or other health conditions, a supervised exercise program is safest.

Questions to ask your doctor about physical activity

A doctor can help answer questions you have on physical activity and point you to resources that can help you set up an exercise routine. Consider asking your doctor:

• How will exercise improve my health?
• What type of exercise should I do?
• Are there weight limitations or specific exercises I should avoid?
• How many times a week should I exercise?
• How long should I exercise each session?
• How strenuous does my exercise session need to be to gain these benefits?
• Should I do more than one type of exercise?
• What community resources are available to me?
• Who can help me set up a safe exercise program?

More Information

Physical Activity and Cancer Risk [2]

Risk Factors and Prevention [3]

Last Updated: June 09, 2011