It is important as a fighter to maintain cardio whilst doing wieghts. you do not want to be huge and get puffed easily in a fight. cardio builds your slow twitch muscle fibres up which builds your endurance, power lifting will give you more fast twitch muscle fibres, used for power. as a rule of thumb my trainer has always said you should be about 50/50 of slow and fast twitch fibres... so my suggestion is to do pretty much an equal amount of work on cardio and heavy weights.
