Originally Posted by MagnaNasakki
Add pull-ups to that and you have my core workout. It's important to keep boxing at the forefront of your boxing. You are training to feel better in a fight, with punches flying; If you aren't punching and/or getting punched at, nothing will be good enough. Beyond that, lungs and heart and legs are what you need to last in a fight. Everything else if useful window dressing.
Skipping road work for swimming and stuff is starting to become fashionable, and it can work. Juan Diaz, a recent fighter with an unbelievable gas tank(Possibly the best work horse fighter of the past 10 years), did swimming and some stairs and rope, and that was pretty much it, and he had the best gas tank in the sport.
They're essentially the same.
Also Wladimir does swimming now and he doesn't seem to gas anymore. (A 245 pound man can't run without hurting his knees anyway)
A treadmill is probably better for your knees too.(Because of shork absorbment)
Though running on a treadmill is easier than normal running (less air friction) so you either have to run at a higher pace or longer.
Treadmills with even more shock absorbment are even better for your knees.