Hello,
Thanks for posting your query.
It is good that you are considering exercise to control your weight and back pain. Increase in weight would contribute to the back pain because our frames are meant to carry only a certain amount of weight and increase in weight increases the pressure on our weight bearing joints ( the hips ,knees , ankles and back).
It is best to start with mild aerobic exercises and swimming. Avoid weight bearing exercises. Do only mild aerobics which does not put your back to strain. You can discuss about this with your Gym instructor.
You may do 'back strengthening exercises' also. Unfortunately those are difficult to explain in words and beyond the scope of this answer. But that you can learn from your physiotherapist or from images on internet.
I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Praveen Tayal.

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