PHB chapter 7, "Using Ability Scores", mentions that it's possible to "lift" more than one can normally carry:
Push, Drag, or Lift. You can push, drag, or lift a weight in pounds up to twice your carrying capacity (or 30 times your Strength score). While pushing or dragging weight in excess of your carrying capacity, your speed drops to 5 feet.
It seems implied that movement is impossible while lifting a weight that is too heavy to carry—otherwise, one could circumvent the movement restrictions on pushing and dragging by opting to lift the weight instead.
What does it mean to "lift" in this context? Off the ground? Overhead?