Peter Attia· MD
by elevating your heels in something like a barbell squat my preferences honestly on a Smith machine because it really controls the movement pattern — and you only go forward so and so people know the Smith machine is the squat bar that has the hooks on it that's in tracks right so the part the path is vertical and it's controll it's completely fixed so — I love that that exercise I think targeting my quads that's been a huge help