The upward force gives us the upward proper acceleration on the ground, making us non-inertial as Einstein predicted. This way, falling objects (inertial) seem accelerating. So, which one is correct? The surface of the Earth is accelerating upwards, thus giving us that upward force. If this is true, the surface is accelerating at what rate? OR We are trying to follow the geodesics of spacetime, but the mechanical resistance of the Earth forbids that. Thus, we are pressed on the ground and there is an upward force exerted on us. I would like an explanation on this. Thanks.