Chessboxing? Seriously?
For the benefit of the uninitiated, chessboxing combines the ultimate mental sport and the ultimate physical sport, with alternating rounds of chess and boxing so that a single chess game is fought in parallel with a boxing match. Checkmate or knockout wins, whichever comes first! You start with a round of chess, followed by a round of boxing, then another round to continue the same chess game, and so on and so forth. Each player has twelve minutes on his clock for all moves, so there is a maximum of six four-minute chess and five three-minute boxing rounds. The same people box and play chess, a common misconception is that there is a handover between a chessplayer and a separate boxer.
Perhaps I can be the first to suggest really mixed martial arts — or Go-MMA?