In last month i have developed a habbit that when i work on heavy bag i dont do 3 min intervals, i just work 20-30 min non-stop, i do have lot of endurance so i can go pretty hard at it, and for me it is much more fun and chalenging doing it non-stop. I do 3 min intervals on mitts and speed bag, i do sprint intervals also. So i just wanna know is this bad way to do heavy bag in if it is what are the pros and cons of it ?