Drilling 2*4
One explanation that most people seem to understand is this:
If you are using a drill on a wooden plank (ie. 2*4), you are applying antitorque with your arm. It's easy to see if the drill hits a hardspot, your hand will be turned around by the increased force of the drill.....increased torque. So you have to hold it harder to avoid the whole drill to spin....increase antitorque with your arm.
Like stated above....action vs. reaction!