In boxing, you see it less in jabs and more in power punches...the step and rotation of the hips transfers that weight and torque behind the punch. Some of the best boxers to watch doing this are Ali, Holmes, Tyson, Floyd Mayweather. All four had/have solid boxing mechanics- plus a greater understanding of how to maximize punching power, without necessarily letting your opponent know. It is harder to see in footage of Ali and Holmes since all of their fights are pre-digital; in Tyson's early vids and any of Mayweathers you can see these principles put to devastating effect.
Sir Edward mentioned this some months back during a free-play session after the last knighting w/regard to cutting. Excellent point.