Sometimes I hit the bags for a marathon pass to try to go as long as possible.

Sometimes just fast, sometimes a combo of fast and slow, and sometimes with weights in between it all.

My hardest heart pump though comes from doing fast and hard left-right combos one after another, then going to right-left, then left-right-left, and just mixing those up. THAT gets my heart going. My heart is the limiting factor and not my muscles in that workout, whereas in all others it seems to be my muscles are the limiting factor, especially my damaged right shoulder.

What bag workout gives your heart the hardest pump?