Could be China with those acrobats that travel around to perform across our USA & several sports in the Olympics. Also, they always have those pics of people, including seniors, doing those exercises in the park. I don't know how many of the citizens do those exercises & other sports. From what I've heard, they can't wait to get off their bikes & into cars & leave The Third World behind. We have little room to blame them for doing that. Who would want to bike in that pollution? Whether they all exercise in their living rooms or in the classrooms & workplaces in the morning, I simply don't know. That is the picture we sometimes see portrayed.
We do have quite a lot of people exercising now in the USA & quite a few devoted little league players. As far as spectator sports, well, they do a lot for a few athletes, but definitely not for the spectators watching at home on the tube. There are quite a few hikers & bikers now, but other countries may have far more participants in all kinds of athletics. I've never seen any statistics on it.
That's tough, but I would say China or Brazil.
I could be wrong but I will say Spain due to their love of soccer.
guessing Germany