Evidation

Evidation isn’t actually a game, but it does a decent job motivating people to work out. The app basically pays you to do fitness stuff. You won’t be able to quit your job or anything, but you should get enough to spoil yourself with something occasionally. Basically, the app keeps track of your various stats, and academics use it as source material for studies. Every time you log your stats, you get points. You eventually trade those points for prizes. Since there are prizes, this totally counts as a game.