So I was at the gym today, running on the treadmill, when the question hit me:
If I run with the treadmill on incline, I burn more calories. Since I run at the same speed, kinetic energy is constant, and since I am not travelling towards the sky, the potential energy stays constant as well.
So I come up with a hypothesis : Running on incline burns the same amount of calories than running without any incline.
I immediately dispose of this since I clearly tire a lot faster when running on incline, so obviously I'm doing more work, hence exerting more power.
So my question remains the same : Why does running on incline burn calories faster?