Although many factors contribute to the development of obesity, it is generally accepted that individuals become overweight and obese because they regularly consume more calories than they use doing physical activity.

The latest study conducted by the University of Bristol recorded the activity levels of 5,500 12-year-olds for at least three days using a special Actigraph activity monitor.

This monitor was fitted on a belt around each child's waist and recorded time spent on moderate and vigorous activity.

Body fat was also measured using a special X-ray emission machine.

Results from the survey found that those who had the most amount of fat were the least active.

Chris Riddoch, the lead researcher in the study, found that doing 15 minutes of moderate exercise a day lowered a student's chances of becoming obese by almost 50 per cent.

The activity needed to achieve this benefit was equivalent only to a brisk walk, or one that made the student a little out of breath.

Some activities that make you out of breath:

Brisk walking

Climbing stairs

Playing dodgeball

Playing football

Swimming

Hiking

Dancing

Skipping

Riding your bike

How active are you?

Are you physically active for at least 30 minutes each day?

Do you do moderate or vigorous exercise at least three times a week for at least 20 minutes each time?

If your answer is yes to both questions, then continue the good work.

Try to vary your activities so you don't get bored with the same routine.

Keeping fit during your teenage years will lower the likelihood of your becoming obese, or suffering from heart disease, broken bones, bone loss, diabetes and cancer in later life.

If your answer is no to both questions, then you need to start building regular exercise into your daily routine.

Try to choose activities you think are fun. Join a dance or aerobics class with friends, go hiking at the weekends with your family, or play team games such as basketball or dodgeball at lunchtime or after school.

There are so many reasons to be active besides improving your health. Exercise helps improve your mood, helps you build a positive self image, gives you more energy and helps you feel better about yourself.

Find an activity buddy because it's more fun exercising with someone else. Then make an appointment in your diary every day to do some exercise either with friends or family.

Be a role model for the rest of your family and initiate activities you can all do together.

Answers

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B. 1. d, 2. c, 3. a, 4. b

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