Some advices for people which use computers:
It‘s very important to relax the eyes so you should sit properly with your back straight then you look to the left side, after to the right side and you repeat this movement slowly without turning your neck or head. Then you do the same way but to top and bottom.
Another thing you should do to rest your eyes is to look into the distance from time to time.
It’s a blood circulation problem for the legs because of people keep a prolonged static posture, so you should try to stand up every hour, more o less, to stretch your legs or walk a bit.
To keep your hands in good health you should roll your wrists regularly when you spend a lot of time typing and you extend gently the fingers back first one by one, after all of them at the same time.
Finally, in order to stretch your neck you should flex your head forward and backward and from the right side to the left side.