Suggest Solution To Ease Body Movement And Leg Pain

Hi! I am a 25 year old woman and my weight is 41 kg. My height is 5 feet and 3 inches approximately. My problem is that I do office job in which I have to sit on the chair for eight hours working on the computer. I have pain in my legs often especially at weekends. I do not feel like walking or doing anything. Its hard for me to do the domestic chores that require movement of the body. I feel like taking rest all the time on weekends. Please guide me about this problem and tell me how can it be resolved. Thanks!