>>7603
>not mma which has devolved into its own style
BR floor manhug homosexuality does not represent MMA nor real fights, if you want to fight some dude in the streets it is highly frowned upon to fight him in the ground and if you are going to fight to kill the one who gets to the floor first very usually loses when getting kicked to death.
>muay thai,pro wrestling, water polo
Real Muay Thai aka the military-taught one has some form of catch wrestling movements and last-ditch maneuvers you don't see in gambling matches-style Muay Thai, if you encounter one such fighter you might want to ask him or just get a MMA-Tracker pass and look for tutorials.
Still that answer seems to imply you want real leg strength as water polo develops such thing along with some wing back (?, i mean the muscles between arms and lower back).
My rec is Muay Thai for its 8 (9 if you count head) striking point system and quick easy grappling that seems instinctive, then go for Complete Savate to develop heels and feet with shoe techniques (as opposed to shin kicking of MT) also because Savate has nasty tricks that can end fights easily like knee pushes and ankle breakers plus don't forget they also teach knife fighting and baton/stick stuff. Do not underestimate real modern Muay Thai and Integral Savate, the systems are very useful and a boxer won't knock you out if they cannot reach you in the first place.
>climbing plus acrobatics
>track and field
>decathlon
Not even the late Bruce Jenner could control so much, stick to base acrobatics and do tons of cardio if you want to compete (perhaps not professionally) in those games. Fighting system is another story and won't do much favors if you also want to do all those things. If it helps then just jog once in a while and swim like crazy.