Hello, Thanks for your query. It seems that your increase in weight; wrong body posture; inadequate exercise and reduced muscle tone is taking a toll on your back. For pain to go, it takes not only rest (on a comfortable bed) but also avoidance of particular positions (during work, rest or recreation). During the day don t sit in one position for more than an hour and take frequent stretch breaks. Do not bend forward to lift things up, bend the knees and hips for that. Also discontinue any strenuous activity or exercises for some time. I suggest you to try back strengthening exercises by extension of the back muscles which can be taught by your Physiotherapist. This will help to relieve the possible muscle spasm which causes the pain. You may go for a physical examination by your Orthopedician to rule out any spine related pathology. You may be prescribed pain killers and/or muscle relaxants which should give you relief. Physiotherapy may also be advised if necessary. I would suggest you to try swimming as this will help most in back conditions. I do hope that you have found something helpful and I will be glad to answer any further query. Take care