lifting is not meant to be specific to your sprinting. Bolt and tyson both use machines and they do some stuff (i can guarantee) that would make you wtf? when you see.
But as I was saying, the point of lifting is to provide a stimulus and strengthen the neccesary muscles. deep squatting does more to strengthen the posterior chain than parallel squats do, however, if your parallel squat got to a certain level… then you’d have enough posterior chain strength anyway, and atg squatting wouldnt make much difference…
In my next GPP, im planning on using both… and progressing both.