1. Stand up from your chair every 30 minutes. Standing up engages your core muscles and the major muscle groups in your legs. Carefully try to get to your feet without using your arms to press upwards. | 2. Use a large exercise ball as a chair, which encourages better posture and improves core strength. | 3. Stop typing and stretch your arms in front of you. Rotate your wrists in gentle circles, first in one direction, then the other. |