In Conrun you can race on one of many running tracks or you can compete in a virtual gym against AI by doing pushups, squats, crunches and other exercises.
You really do workout.

You unlock each stage by winning the previous one.

Even if you lose, you will still get XP that unlocks cosmetic items. The more you do the more XP you will get.

Game is divided in to 10 tiers.
Dificulty level increases with each tier.
Amount of earned XP also increses with each tier.

It's time to build some muscles.