Bump and run
“Bump and run” describes one method of pushing a buggy uphill in which the pusher shoves the buggy ahead of them and then runs to catch up before shoving it again. The main alternative method, sometimes called the Stiff Arm, is to maintain contact with the buggy while running. Which method is fastest is a matter of debate but the ideal strategy has to do with the weight of the buggy, the strength and speed of the pusher, and the steepness of the hill.
An example of both pushing techniques on Hill 1. PiKA uses the “Bump and Run” while KDR uses the “Stiff Arm”.