Im not an expert on this stuff, but you should be able too...
Dont expect a high FPS, your probably never getting 60 unless yuo only have 1-2 bodies that arent colliding.
Just try to avoid too many objects and excessive collision and you will probably keep around 30 FPS on average.
NOTE: For the most part I dont have any idea what im talking about and im probably wrong, so if someone else like dan posts on here disregard this post.