all I know is if it the purpose is for sports. any real muay thai instructor (I mean knows/teaches the the competitive martial art & not just using muay thai style kickboxing as a gym cardio workout) will tell you never use weights in hands or bands for punching. it is actually counterproductive to refining your technique. but you go to a gym where muay thai is just the basis for a general workout for people bored with or by other aerobics, they have you doing all that.