Shunsuke Nagasaki and his brother both performed incredibly well at the initial stages of Ninja Warrior (not sure if they both finally made the title Ninja Warrior). In terms of overall physical fitness (not necessarily combat or martial arts skill), the guys who make the title Ninja Warrior are even fitter than most PTIs, OCS officers, Commandoes or Rangers.
It's impossible to be a Master of All Trades, of course.
It's like in the movie (now showing) District 13 : Ultimatum. The two main heroes are ultimate specialists in their own areas : one in martial arts - Damien Tomaso (actor Cyril Raffaelli), the captain of the commandoes; the other in Parkour or free running - Leïto (actor David Belle, the original founder or Parkour).
That's not to say Cryil can't do free running (he's also a Parkour expert) and that David can't do martial arts (he holds a black belt in several martial arts), but when you get to such high levels in an art or science, you'd want to specialize and boldly go where no man has gone before, for your own personal achievement, accomplishment, satisfaction, gain, name and fame.