Physical activity and cancer risk

Being physically active – move more and sit less – reduces your risk of cancer of the bowel, breast (after menopause) and endometrium. Vigorous physical activity can protect against breast cancer in premenopausal women.

Physical activity is any activity that gets your body moving and speeds up your breathing and heartbeat; including walking, running, swimming, team sport, exercise classes or housework. Being active also lessens the time we spend sitting, e.g., in front of screens.

Physical activity also helps to prevent weight gain. Being above a healthy weight is a risk factor for many cancers including bowel, breast (after menopause), endometrium, kidney, pancreas, liver and oesophagus.

Even if you are a healthy weight, physical activity reduces cancer risk.

How physical activity reduces your cancer risk

Researchers are still investigating how physical activity reduces cancer risk. However, there are several likely reasons:

• When you are active, your body produces less insulin and insulin-like growth factor, which promote the growth of cancer cells.
• Physical activity may help reduce different hormone levels that are linked to cancer.
• For bowel cancer, physical activity helps move waste through the bowel faster, limiting the time harmful compounds stay in contact with the bowel lining.

How active should you be?

Australia’s Physical Activity and Sedentary Behaviour Guidelines encourage adults to be active every day in as many ways as possible.

Adults should do 2½ to 5 hours of moderate activity or 1¼ to 2½ hours of vigorous activity every week, or a combination of moderate and vigorous activities.

What is moderate and vigorous exercise?

Moderate intensity activities increase your breathing and heart rate:

• brisk walking
• swimming
• golf
• household chores

Vigorous intensity activities make you huff and puff:

• jogging/running
• aerobics
• organised sports such as football or netball
• fast cycling

If you have a medical condition or are unsure about your health, ask your doctor for advice before starting any new physical activity.

If you are currently inactive, any increase in activity is beneficial.

Sit less

Reduce the amount of time you spend sitting by organising walking meetings or a lunchtime walk. Break up sitting time with a short stretch or a few exercises or a short walk.

How can I get more active?

Make time for a walk

• Walk with a friend, work colleague or join a walking group.
• Turn off the television or computer and go for a walk instead.

Plan activity into your daily routine

• Take up a sport or join an exercise group or a local gym.
• Have some active fun, e.g. cycling, bushwalking, surfing, team sports, dancing.
• Be more active on the weekend, on days off or when catching up with friends. e.g. go for a bushwalk or play cricket in the park.
• While watching television, do some simple exercises such as sit-ups or lunges.

Use active transport

• Walk, cycle or scoot part or all the way to work, activities or taking children to school.
• Catch public transport and walk to the bus or train stop.

Increase incidental activity

• Take the stairs instead of the lift and walk up and down escalators.
• Stand up to change the TV channel.
• Spend time gardening or mowing the lawn.

Remember to slip on clothing, slop on sunscreen, slap on a hat, seek shade and slide on your sunglasses to protect yourself while in the sun.

Supporting healthy lifestyles: Government policies can influence the food environment, how and where food is priced, marketed and sold; and the physical environment, how easy it is to be active. Read more about supporting healthy lifestyles.