Aug 31, 2018 · 1 min read
Hi Chris, great article as always.
Two remarks:
- “ the high-bar squat may therefore involve a proportionally larger hip extension torque, while the low-bar squat may involve a proportionally larger knee extension torque.” Its the other way round.
- “ Since the hamstrings are both hip extensors and knee flexors, this means that the contribution to system force required from the two-joint hamstrings is very high, because they must work both to extend the hip and also to flex the knee.” This is misunderstandable. In a deadlift, as first order force, the knee does not need to be flexed, but extended. But one of the knee extensors, the rectus femoris, is also a hip flexor, increasing the demand of hip extension. And as you point out, the hamstrings are also knee flexors, increasing knee extension demands while extending the hip. Greg Nuckols therefore argues for a greater participation of single-joint muscles like the glutes for minimizing those interference effects (when aiming for highest amount of weight lifted). He also states — citing study data — hip extension demands in the low bar squat still as fairly low despite being somewhat elevated in comparison to the HB squat.