Tons of cardio, mostly running and rope work.
Long runs (not jogging) are done at about 60-70% your top speed so it is a quick pace. You need stamina and the capacity to work over a long period of time.
Rope work builds your shoulders, arms, calves builds coordination and cardio.
Strengh/Resistance training - calisthenics to get back in shape, weights + plyos to build your strength/speed.
Rounds and rounds of pad work + sparring. You're gonna love pyramid drills and round robbin sparring (hey a fresh dude, while I'm gasping for air and dripping with sweat!)
Heavy bag