I'm a firm believer in sparring while conditioning. Someone here already said it I think but these guys are training to fight so they have to fight each other to get there reflexes and techniques down. When my guys complain about sparring I'll mix it up a little bit. Here's a couple examples of how you can shark tank someone (round robin) or take your team to a track/stairs/hill to get them running and sparring. Both work tremendously well in getting your athletes in shape!