For quad growth
For quad growth, hack squat rates well ahead on our research criteria: more of the work on the quads, more stretch.
Both are good choices that train the quads the same way, so they swap freely. Rotating between them every few weeks is an easy way to vary your training.
The research score comes from these, scored by hand from the studies. Lifter scores appear once an exercise has 10 ratings. How scores work
Hack Squat. Deep knee bend under stable, heavy load: the quads are clearly the limiter.
Safety Bar Squat. A more upright squat than a back squat, which suits the quads and spares the shoulders.
For quad growth, hack squat rates well ahead on our research criteria: more of the work on the quads, more stretch. Both are good choices that train the quads the same way, so they swap freely. Rotating between them every few weeks is an easy way to vary your training.
Hack squat is easier: it’s easy to learn, while safety bar squat takes some practice.
Hack squat needs a machine, so for most people it’s a gym exercise. Safety bar squat needs a barbell and a squat rack, so for most people it’s a gym exercise.
About the same: both rate Strong for joint and recovery cost in our research rubric.