Stretching should be a crucial part of any routine, whether you work out in the gym, at home or in the park, or if you play sports and ride your bike. Muscles react to what they are asked to do, contracting and shortening if they are worked hard. In reality, this “shortening” is a building of tension, as they cannot really change their length. But it can have a significant effect on your posture, performance and mobility.

Particular areas of your body become “tighter” as a result of exercise, most commonly your thighs, hamstrings and the outsides of your legs. It is important to keep these areas supple as lack of flexibility is one of the key causes of back pain and impaired knee function.

But it's not just sportsmen and women who need to stretch: inactivity is just as big a culprit in creating stiffness. If you're sedentary, your muscles become tighter, your joints don't move freely and you become stiff.

It sounds obvious, but being mobile is crucial to retain mobility. For instance, if you spend a lot of time working at a desk, your posture will be drawn forwards, building tension in your chest and shoulders, putting a strain on your back. Yet, just a few movements, done regularly, will improve your posture and prevent long-term damage to your back.

It is also vital to keep yourself active as you get older. It needn't be structured exercise: dancing, gardening, and spending a small amount of time moving your joints and stretching your muscles can leave you feeling more mobile and, therefore, younger, too.

When should you stretch?

It is better to stretch in the morning once you have been up and about for a bit. So if exercise is not part of your regimen, try stretching mid-morning. This can be tricky if you work in an office, so don't worry if you have to leave it until you get home; it's just as effective.

Pre-workout: You don't need to stretch before exercise, but you do need to warm up. For example, if you are about to play tennis and you can move your arm in all directions - above, sideways and behind you - without limitation, you are already stretched. Therefore, a range of pre-exercise warm-ups that will simulate the movements of the activity you're about to embark on will provide all of the “stretch” that you need.

Post-workout: Stretching is a must here as it alleviates the muscular tension that exercise creates. And while it will not prevent next-day muscle pain, it will reduce stiffness and increase mobility.

Which areas do you stretch?

Focus on the big muscle groups, such as thighs, hamstrings, chest, upper and lower back. Working on these key areas will mean that you've stretched all of the muscles that affect your posture and you'll retain good postural balance.

How long should you stretch?

Post-workout, you should hold each stretch for 8 to 12 seconds. If you want to increase your mobility, hold each stretch for between 20 and 60 seconds.

Hamstrings

This stretch should be felt along the back of your thigh. Lie on your back with your left knee bent and foot flat on the floor. Raise your right leg in the air and place your hands behind your calf or thigh, and bring your knee in towards your chest. As you do this, slowly straighten your leg so the sole of your foot is facing up to the ceiling. Pull your leg in as close to your body as you can. Repeat two to three times on each leg.

Quad standing stretch

This time you're aiming to feel it along the front of your thigh. Stand up on one leg and clasp the foot/ankle of your other leg behind your back and bring the heel up towards your bottom. Keep your hips facing forwards. For a deeper stretch, push your hips forward. Repeat on the other side.

Hip flexer

Start by kneeling and putting your right leg out in front of you with your foot flat on the floor. Your front knee should be bent to 90 degrees and at 90 degrees to your hip. Tilt your hips forwards, keeping your torso straight and upright. Repeat on the other side.

Torso

Lie on your back with your arms outstretched on either side. Bend your right knee and bring it up to hip height. Keep your left leg straight and bring your right knee over your body to the left side. Place your left hand on your right outer knee and press down gently. Put a pad or object on the floor underneath your bent knee to make sure that that you don't stretch your lumbar spine. You should feel this along the side of your torso and into the side of your abdomen. Repeat on the other side.

Upper back

Place your hands together in front of you and then push out away from you, keeping your hands clasped so you round out your upper back. You should feel the stretch between your shoulder blades. Repeat three times.

Outer thigh stretch

You should feel this along your right outer thigh and around your hip and/or knee. Stand on your left leg and cross your right leg behind your left. Lean over to the left, pushing your right hip out to the right, keeping your knee straight. Repeat on the other side.

Shoulders

Place your elbow against a wall at a height that is level with your shoulder. Your hand should face towards 12 o'clock. Turn away from the wall, leaving your elbow in place, so you feel the stretch in the front of your shoulder. Repeat on the other side.

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