Exercises to avoid

I had surgery on Friday (UK) and so far my recovery is going smoothly. I am resting a lot but also pottering around the house quite happily.

Thinking forward, I am going to see a PT again two weeks into recovery and plan on asking them about how to strengthen my core to avoid future issues. In the meantime I would like to learn what I can and can't do exercise wise in the long term. I am 44 and overweight and had finally found an exercise I loved doing (lifting weights) but know I am going to have to be very careful if I am going to continue. Can anybody point me in the direction of any reading or research to get me thinking about the future? Thanks very much