Sitting in front of a computer all day sounds like it should be easy on the body. It's not exactly manual labour, after all. But it's the little things we do that lead to pain. The problems will probably be familiar to many: a strain in the neck, a spasm that shoots down to the shoulder blades, difficulty turning the head and a numbness or tingling in the arms. Marla Apt, a Los Angeles-based yoga instructor who is in town this week for the Asia Yoga Conference, says most of these injuries can be attributed to incorrect postural habits. 'Our interaction with many of the conveniences of modern life causes the majority of repetitive strain injuries,' she says. Spending hours slumped forward in a chair makes the upper back and upper arm muscles lose the tone which helps to hold us upright. The muscles in the chest and the front of the shoulder become disproportionately tight. As a result, the shoulders are pulled forward and down, the upper trapezius muscles (between the neck and shoulders) become hard and the head projects forward. A few minutes of simple yoga stretches interspersed through the work day will help to relieve the pain. Apt, who will conduct a 'yoga for the neck and shoulders' session at the conference on Thursday, explains: 'Yoga strengthens weak parts and relaxes and stretches overused areas that are holding tension.' Below, Janet Lau, an instructor at Pure Yoga studio, demonstrates seven stretches suggested by Apt that you can do in the office or any workplace. For more details on the conference, which runs from Thursday to Sunday, visit www.asiayogaconference.com . Upward extended arm pose Stand with your back against a wall, with feet hip-width apart. Press your thighs and shoulders against the wall. Raise your arms straight overhead. Reach the hands upwards while releasing your shoulders down and keeping your lower back against the wall. Rotate your arms so that the biceps revolve back towards the wall. Continue reaching upwards with the arms straight as you release the trapezius muscles away from the ears. Exhale and lower arms back down by your sides into Tadasana. Cow face pose - arms only Raise your right arm, bend the elbow and place your hand on your upper back. Bend the left elbow and place the back of the hand between the shoulder blades. Clasp hands or use a belt. Turn the upper left arm outward and roll the left shoulder back and down, while extending the right elbow. Continue to expand the chest without turning the torso or arching the lower back. Return to Tadasana briefly before repeating on the other side. Clasped fingers pose Interlock fingers snugly. Turn the palms away from your chest and stretch the arms in front of you, parallel to the floor. Keep the arms straight and raise them overhead. Try to take the hands farther back so that the arms come beside the ears. Without dropping the arms, release the trapezius muscles. Exhale and return to Tadasana. Repeat with the hands clasped the other way, so that that the opposite index finger rests on the top. Side arm pose Stand with your right side facing the wall. Place your right palm on the wall in line with the shoulder, with the hand turned outward so that the middle finger is parallel to the floor. With the right elbow slightly bent, turn your upper arm out from the shoulder socket. Press the entire hand into the wall. Drop your right shoulder back and down, away from the ear, and straighten your right arm. If the wrist hurts, try facing fingers upwards. Return to Tadasana, the basic standing position, and repeat on the other side. Cobra pose Lie face down. Place your hands below the shoulders. With your forehead on the floor, lift the shoulders, expand the chest and press your tailbone down. Roll your shoulders back as you lift the head and chest off the floor. Arch the upper back, keeping the tailbone pressed down. Lengthen forward from the lower abdomen towards the top of the sternum. If your chest feels open and your neck feels free, look up . Twist on a chair Sit on the right side of a chair and place your feet flat on the floor, hip-width apart. Turn to the right and place your hands on the top corners of the chair's back. As you inhale, lift the sides of the torso and roll the shoulders back. Spread the elbows apart and expand the chest. As you exhale, turn your chest to the right. Lift and turn the chest without pushing the lower back forward. Keep weight on both feet equal and both hips even on the chair. Exhale and revolve the chest to the right and turn the head to look over your right shoulder. Exhale and turn to the centre, then repeat on other side. Half forward bend at wall Stand facing a wall. Place your hands on the wall, shoulder-width apart at chest height. Spread the fingers. Without moving your hands, step back and lower your chest towards the floor until the spine is parallel with the floor. Place the feet directly under hips, legs perpendicular to the floor. Look down. Rotate the upper arms out until you feel the shoulders spread away from the neck. Push your palms into the wall and spread your shoulder blades. Press the heels into the floor and your thighs back as you expand the rib cage.