Never start training without a 15 minute warm-up.

Before doing anything it's important to first warm up your muscles to prevent injury. Begin by jogging gently on the spot for five minutes or so to get your circulation going. This will increase the blood flow to your muscles, warming and relaxing them. Then stretch the major muscle groups to prepare them for more vigorous use.

The following exercises are static stretches, so there should be no bouncing, no getting out of breath, no straining.

Hold each position for 10 seconds, and make sure you feel the stretch in the correct muscles. Pay particular attention to your back and knees, since these are vulnerable to injury.

If you have an existing injury about which you are worried, it is always better to protect it than to re-injure it. If in doubt about an old injury or a medical condition, consult your doctor or physiotherapist.