His weight against Peter McNeeley was 220lbs; which was what he reached and surpassed in the 1980's. Hell in the second Holyfield fight he was 218lbs, which was very lean. His weight went off the rails around 2000. Against Golota he was 222lbs yet 1 year later against Nielson he was 239lbs.
What's with all your Tyson threads? Is there no other boxer you'd like to rap about? To answer your question, Tyson didn't lift weights in prison. He didn't spar or hit the heavy bag either. All in all, he never even put on a glove.
He said he did a lot of press ups. Not sure if they even had weights in his prison. A lot of prisons don't believe in allowing weight lifting.
From his biography, he mentioned he did alot of shadow boxing and push ups, and there was something about weight training as he was relieved he was still in good shape as he was courting some overweight Parole officer by picking her up against the wall!
