The answer to your question is,
People who avoid them.
-Mabel <3
Answer:
C, This is my answer as preventing is better than curing at the end.
“Not only the above but also a heavy bag doesn't move, depending on your style you may end up chasing or running away a lot during a match.
The heavy bag is just punching with a little movement here and there in the ring your work rate has to be much higher otherwise your doomed.
Plus when you take punches that can fatigue you.”
honestly found this on yahoo answers lol, hope this helps!!