JimZipCode wrote:How do you measure "work" with exercises, anyway? What I remember from freshman physics is, if you snatch with 135 #, then drop the bar, the amount of "work" done is zero: because the bar is right back where it started.
No. The amount of work done
to the bar
by the lifter = weight x height. The bar then gets the free ride down.
Likewise if you have someone who can't do a pull-up (like, uh, me), and you start them off with doing negatives off the pull-up bar; then the whole time, as they are sweating & straining and working up to a real pull-up, the amount of "work" done is zero because the force is acting against the line of motion.
Actually, at first glance you might think it would be energy dumped into the muscle, and it is if you kip or use a stretch of the muscle to store energy and rebound.
But if done slowly, it is more like a Harrier hovering and slowly descending. While still coming down, it is using up energy. Sports Science hasn't figured out isometric or negatives too well as far as where the energy is going.