Video going over the training routine of Kell Brook here; This content is protected Brook has been working with a team at Sheffield Hallam University, based off this they put out this paper "strength and conditioning recommendations for professional boxing"; https://www.ingentaconnect.com/content/wk/ssc/2016/00000038/00000003/art00010 The paper sits behind a paywall though so you might not be able to see it. Most of it is covered in the youtube video. *This doesn't cover the technical aspect of boxing training just his strength and conditioning routine.
Awesome. This part is the most important part of boxing success, without being an athlete you're just a bum.