Yes because you are trying to meet the bar wherever it ends up for efficiencies sake. Problem is, it freaken weighs alot, so you have kilos of weight driving you down at 9.8m/s squared which you are trying to stand up with!
And you you are trying to meet the bar while it is still travelling upward, but you aren't strong enough so it drives you back down. Then in the fraction of a second that its driving you down your nervous system realizes this and responds by trying to catch the whip of the bar, which produces a second verticle momentus drive in the weight and you drive up at that instant.
Alot more things are happening than just you eccentrically decelerating the bar.
Oh and gravity wont wont help the bar decelerate at all it will in fact help the bar accelerate and crush you!
Think of it like this if there is no contraction when you meet the bar it means you are a limp noodle and it will hurt you. This is bad!
NOTICE: Pierre Auge's opinions are subject to change at any time and without prior notice.
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