Originally Posted by
Jason Donaldson
The ideal bar path is vertical. That doesn't mean the bar path is exactly vertical. The Smith machine does not allow any sagittal (front-back) changes, and this is bad for multiple reasons. If the bar's not over the center of the foot, it cannot GET over the center of the foot, for example. The combined center of mass is what needs to be over the center of the base of support (i.e. the feet) - the bar acts as a useful proxy for this, especially as the bar gets heavier, but it does change slightly throughout the warmups, and over time. The Smith machine does not allow the lifter to adjust this naturally - it must be exact from the top down, and at the top is not necessarily the best place to figure this out. As a result, risk of injury goes up - there are no adjustments available on the fly.