What is exercise?

Exercise is any type of physical activity (body movement produced by contracting skeletal muscles), that is done to build skill levels or fitness. You need to exercise if your usual levels of physical activity are too low to keep you healthy.

Physical activity is a normal part of most people’s lives as part of their work, play or day-to-day activities. Things like housework, walking to and from work or school, or playing with the kids are all physical activities that can help to keep you well.

There’s a minimum amount of activity that you need to do to stay healthy. The intensity of the activity needs to be high enough, and you need to do it for long enough.

  • Low-intensity physical activities are things you can do while you’re having a conversation, like going for a walk
  • Moderate-intensity physical activities make you a bit puffed and make it a bit hard to speak while you’re doing them. Going for a swim or walking quickly are examples of moderate-intensity exercise
  • Vigorous intensity physical activity stops you from being able to speak comfortably while you’re doing it. Things like running, playing football, or a fast bike ride are examples of vigorous physical activities

The opposite of being physically active is being sedentary (sitting or lying down). Spending a lot of time being sedentary, like sitting at a desk all day or spending hours on the couch watching TV or gaming, is bad for your health.

Spending too much time being sedentary, or not doing enough physical activity, increases the likelihood of developing long-term health problems like obesity, diabetes and heart disease.

The World Health Organisation and the Australian Government recommend amounts of time and types of physical activities that people should undertake, depending on their age. The guidelines are developed with whole populations in mind, and there is no one-size-fits-all amount of physical activity that suits everyone.

The Australian Government physical activity guidelines recommend:

Babies (up to 12 months of age):

  • Have multiple periods of activity in between sleeps over a day, including a total of 30 minutes of ‘tummy time
  • Not spend more than an hour at a time when their movement is limited (e.g. in a pram or car seat)
  • Not have screen time

Toddlers (aged 1 or 2 years):

  • Spend a total of three hours each day being active: playing and doing things they enjoy, while exploring and discovering things
  • Not spend more than an hour at a time when their movement is limited (e.g. in a stroller, high chair or car seat)
  • Not have sedentary screen time

Pre-schoolers (3-5 years):

  • Be active for at least three hours each day, including one hour of vigorous activity, like running or playing sport
  • Not spend more than an hour at a time when their movement is limited (e.g. in a stroller or car seat)
  • Spend as little time as possible sitting still or lying down during the day. They should have no more than one hour of sedentary screen time each day

Children and adolescents (5-17 years):

  • Get at least one hour of moderate-to-vigorous physical activity each day, either all at once or broken down into a few shorter periods over the day
  • Include activities that strengthen the muscles and bones — such as running, climbing, push-ups, lifting weights, yoga — at least three days a week.
  • Have no more than two hours of sedentary screen time per day

Adults up to 64 years of age:

  • Try to be active every day
  • Do at least two-and-a-half hours of moderately intense physical activity over a week or 75 minutes of vigorous-intensity physical activity, or an equivalent mix of both.
  • Include muscle and bone-strengthening activities at least twice a week

These recommendations are designed to maximise people’s health. If your level of physical activity is lower than what’s recommended, it is still beneficial compared to if you were less active. For those people who are the least active, small increases can have large health benefits

Who needs to exercise?

Most Australian men and boys should exercise.

About 70% of Australian boys aged 2-5 years get the recommended amount of physical activity for their age group (at least three hours each day, including an hour of vigorous activity). Only a quarter of boys aged 5-12, and about one in 12 aged 13-17, meet the physical activity guidelines.

Just under half of Australian men aged 18-64 meet the physical activity guidelines, but only around a quarter do enough strengthening activity; only one in five meet both the activity and the strengthening activity guidelines. One in four men aged 65 or older meet the activity guidelines.

If your physical activity level is less than what’s recommended, exercise can help to improve your health and prevent disease. If you’re not able to be as physically active as recommended, you should increase your activity level to whatever you can manage. A small amount of physical activity is better than none. Even if you meet the physical activity guidelines, more activity can produce extra health benefits.

Spending more time being physically active can help to reduce the length of time you are sedentary, and also offset some of the bad effects of being sedentary. More than two-thirds of Australian boys have more than the recommended amount of sedentary screen time.

Health effects

The health benefits of exercise

In children, the benefits of physical activity include:

  • Physical fitness (cardiorespiratory and muscular fitness)
  • Cardiometabolic health (blood pressure, glucose and fats in the blood, insulin sensitivity)
  • Bone health
  • Cognitive function (academic performance, thinking)
  • Mental health (reduced symptoms of depression)
  • Reduced adiposity (body fat)

In adults (18-64 years), the benefits of physical activity include:

  • Reduced risk of death from all causes
  • Prevention of high blood pressure
  • Prevention of cancer
  • Prevention of type-2 diabetes
  • Mental health (reduced symptoms of depression and anxiety)
  • Cognitive function
  • Better sleep
  • Decreased adiposity

In older adults, the benefits of physical activity are the same as in younger adults but also include:

  • Prevention of falling and fall-related injury
  • Bone health
  • Functional ability

The health costs of being sedentary

In children and adolescents, being sedentary is associated with:

  • Increased adiposity
  • Poor cardiometabolic health
  • Poor fitness
  • Less positive social behaviours
  • Less sleep

In adults of all ages, sedentary behaviour is associated with:

  • Increased risk of death from all causes
  • Development of, and death from, cardiovascular disease
  • Development of, and death from, cancer
  • Development of type-2 diabetes

What should I do about exercise?

Just about everyone can benefit from moving more, so you should try to find ways to increase your amount of physical activity. Even small amounts of activity can have big health benefits if your current activity level is low.

If you have a disability or health problem that limits your activity, talk to your doctor about how you can gradually increase your physical movement.

If it’s possible, walk or ride a bike instead of driving. Take the stairs rather than the elevator. Go for a walk or find some other activity to do during your lunch break. 

If you’re not doing as much physical activity as recommended, you should find a way to incorporate some exercise into each day. Finding ways to reduce the amount of time you are sedentary will be beneficial to your health.

If you work at a desk, get up and move around regularly during the day. If you can stand at your desk, rather than sit, do that; you might need to gradually increase the amount of time you are standing each day. If you have meetings with one or two people, suggest doing them while walking, rather than sitting around a table.

Exercise is easier for some people than others. Those who are in good health and who are used to physical activity find it easier than others to increase their activity levels, perhaps because they’re more likely to believe their efforts will be effective. For adolescents, having family members that support their efforts at being physically active helps.

Some health problems, like obesity or joint pain, can be causes and consequences of not doing enough physical activity. It’s easier to prevent these problems by being physically active than it is to deal with them after they’re established.

What questions should I ask my doctor about exercise?

  1. Can you help me work out if I’m doing enough physical activity?
  2. Could increasing my physical activity level help to manage any of my health concerns?
  3. Could increasing my physical activity reduce my requirements for medications?
  4. What physical activities would you suggest for me?
  5. Can you help me work towards my exercise goals?
Email these questions to yourself to take into your doctor's appointment.