People will commonly tell me that they know strength training is great for them, but they’re just not flexible enough to squat or deadlift.  They’ve tried!  They can’t get below a quarter squat and this is obviously due to lack of flexibility in their hamstrings, hips, back, or some other thing.  If you think about this for more than a second, you’ll find that even in the low bar squat as explained and demonstrated in Starting Strength: Basic Barbell Training by Mark Rippetoe (the most hamstring intensive of the squat variations), the hamstrings don’t actually change much in length from standing to the bottom of the squat.  The hamstrings cross both the hip and the knee and as the hip angle closes when you go down to the bottom of a squat, the knee angle is also closing.  The net affect is that the hamstrings stay about the same length the whole way down and are acting mostly isometrically.

So, what is going on when a relatively healthy person is unable to get into the bottom of even an unweighted squat? Barring any kind of anatomical issue (a rare thing), it’s a strength problem, not a flexibility problem.  These folks are literally not strong enough to get into this position, so they won’t allow themselves to.  If you don’t believe me, you can have them lightly hold onto the upright on the power rack, or some other stable object, and then have them go to a full squat.  They’ll do it with no problem.

The elderly, very sedentary, overweight, or weak people unable to squat the empty bar will need to do a little bit of work prior to being able to squat with a barbell.  There are a few ways to do this.  I’ve used a band in the power rack, squatting to a progressively lower box, and the leg press.  If you have access to a leg press, it’s probably the most efficient way to get this accomplished.  Keep in mind that folks who aren’t strong enough to squat will generally still be able to deadlift, so they will certainly do so, but you’ll replace the squat with the leg press for a few sessions or weeks until the trainee is able to squat with the empty bar.

Here’s an in-depth video on the leg press and it’s utility in a proper strength training gym.  Remember that it has a very specific purpose that doesn’t include loading it with every plate in the gym and “leg pressing” 900 lbs through 1/4 range of motion.