Padding activities duration estimates refers to adding an extra amount of time to the original estimate of an activity, in order to provide for unexpected delays or events. This is done before the project starts, in order to create a more realistic schedule. Feeding buffers, on the other hand, are additional allowances of time that are built into the project plan during the execution phase, in order to ensure that tasks are completed within their original durations by providing extra time for finishing. This approach involves adding buffers before the start of a task or between tasks, as opposed to padding estimates, which is done before the project begins.