You have a point in that pushing off with the foot is part of a wider "chain of events" that increases reach and propels your COG foward as you punch
However it also adds a flex point in the "chain" that absorbs shock
The human leg is a phenomenal shock absorber Design By Nature to absorb impact and is the final link in the chain that braces your frame to the ground
A jumping punch will never be as powerful as a punch delivered from a deeply rooted flat-footed stance
when you throw a punch from anything but a deeply rooted flat-footed stance you're relying more on speed and momentum that you are on weight transfer
weight transfer is that unique feel of the heavy puncher
Some athletes punches feel much heavier than others even though they may be of similar weight and strength
Try to learn to hit the heavybag with your rear foot well planted
When you get comfortable with the technique you will find that you can impart much more weight to your strike with less physical effort and less chance of counter because your balance is so much better as your COG is resting comfortably not tipping out forward in a falling motion as you miss
I tip out all the time because its the only way to REACH my target but then i regret it because even tho i landed a blow i am off balance and they can hit me very hard
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