How much activity?
How much physical activity you should do depends on where you're starting from.
Your age, general health and current activity levels will determine how far you can push yourself.
If you haven't been doing much for a while, there's good news. Evidence shows that inactive people achieve more immediate benefits from resuming activity than those who are already fit.
Many people's views on exercise were formed during school PE lessons: running on muddy playing fields or standing around in the cold in a T-shirt and shorts while the teacher explained the finer points of the Fosbury Flop high-jump technique.
The trauma doesn't end there. TV images of exhausted amateur marathon runners about to keel over or myths such as "no pain, no gain" and "I'm too old to start" have firmly wedged people to their sofas.
But getting active doesn't mean sweating it out in the gym, running yourself ragged on the treadmill or playing for your local pub team on a Sunday morning in the Arctic weeks of winter.
Physical activity is very broadly defined. On a basic level, it's any movement that makes you feel warm and slightly out of breath.
Someone unfit or overweight may only have to walk up a slope to experience this feeling, whereas an athlete may be able to run quite fast before the feeling becomes noticeable.
Physical activity includes the full range of human movement, from competitive sport and exercise to active hobbies, walking, cycling or activities of daily living, such as housework and DIY.
Adults should do a minimum of 30 minutes moderate-intensity physical activity, at least five days a week. For children and young people the target is at least 60 minutes a day.
You don't have to do the whole 30 minutes in one go. Your half-hour could be made up of three 10-minute bursts of activity spread out through the day.
This can include a lifestyle activity (e.g. walking to the shops or taking the dog out), a structured exercise or sport, or a combination of these.
"You get benefit from the total amount of activity you do throughout the week rather than how hard you push yourself," says Nick Cavill, a health promotion consultant.
'You get benefit from the total amount of activity you do rather than how hard you push yourself.'
Nick Cavill, health promotion consultant
For general health, adults should do a minimum of 30 minutes of moderate-intensity physical activity, at least five days a week. This can be achieved by doing all the activity in one session or through shorter bouts of 10 minutes or more. Older people should take particular care to keep moving and retain their mobility through daily activity. Activities to improve strength, co-ordination, balance and endurance are of particular benefit.
Activities can include:
- Walking or cycling.
- Using the stairs.
- Doing manual tasks.
- DIY
- Gardening
Overweight and obese
The 30-minutes-a-day guidelines can help with weight management. But for many people, especially if there's no change in diet, 45 to 60 minutes of activity each day may be needed to prevent the development of obesity.
People who are obese may need to do 60 to 90 minutes a day to lose weight. Activities such as brisk walking or cycling are considered as effective for weight loss as supervised exercise programmes.