I have not played the Prokofiev Toccata, but have seen several friends play it. My recommendation for a recording is the Martha Argerich debut recital recording. I think that it's absolutely incredible. Her tempo is fast, but the effects the she uses in it are spine-tingling. I love it. :-)
As for lifting weights, I would be careful. Consult your teacher and find someone to help you work out if you decide to go through with it. I knew someone who lifted weights to prepare for a masterclass with my teacher and it actually ruined her performance. Being an individual without naturally amazing technique (and one without the drive to go to the gym), I have found other alternatives to lifting. You can swim (it works the muscles, but doesn't put any strain on your wrists, joints, etc.), or run. You just have to remember that a lot of the power that goes into your playing comes from gravity (dropping your fingers into the keys) and the speed of the keystroke. Building up the biceps, or whatever, will not (in my opinion) gain you a lot of power or control. As for stamina, I'm not sure. That's what your teacher, and perhaps a doctor are for.
I hope that helps. :-)
Mike