Early in my career, I had difficulty breathing during workouts and my performance on the ice suffered. It wasn't until I was diagnosed with EIB and received the proper treatment that I was able to reach my peak performance.
My 'go to' workout is called the Asylum from Beach Body. It's intense training with lots of intervals, core work. It's hard! I travel a lot, so I can take it on the road with me and do it in a hotel room.
One things guys have to remember is consistency... You can't make up for three years of eating poorly in just one workout.