Last night a Strength Faction member posted a great question about the Active Straight Leg Raise in our open forum. It’s perfect timing-this month is Movement and Programming month in the Faction. Our guy wasn’t sure how the ASLR gave us information about the hinge since it’s done on the ground and hinging is done on our feet, and involves a bunch of other joints other than the hips.
It’s a fair question.
So, Chris and I jumped in to give him solid answers.
These are our answers direct from the forum. I’m giving you these because, well, they’re already well-written and I think you’ll get a lot out of them. Also, because I want you to have a gander at the depth of discussion that takes place in the Faction. It’s some real ass shit.
Here’s Chris’ answer:
The ASLR is not a pure hinge test, but it gives us a lot of information to drive decision making when it comes to the hinge. It really looks at three things:
“1) Adequate extension of the down leg
2) Adequate mobility and flexibility of the elevated leg
3) Appropriate pelvic stabilization prior to and during the leg raise”
(that’s straight from Movement, just to be clear)
I just presented this 18 Federal Law Enforcement Agents last week, and got a similar reaction to yours (well, minus all of the technical jargon…), and I kept things very very simple to explain why this test matters.
The first thing I pointed out is that I’ve truly never met/trained anyone with tight hamstrings, which many of them interpreted this screen to test. If our hips are excessively anteriorly rotated, or asymmetrically rotated, which most of us are (0/18 passed the ASLR during their screen), we will see the inability to split our hips without compensation. That anterior tilt, on one side or both, will hold the hamstring(s) in a longer resting position, potentially causing the inability to raise the leg without compensation. Not because it’s tight, but because of the elongated position it’s being held in. This will have an impact on our ability to stabilize our hips, leading to an issue up the chain into our back. Again, it’s more than likely not due to a tight hamstring, but rather a core strength, or hip position. And that is a big deal when it comes to hinging.
From Movement, again:
“The hips are a window to the core. Hip strength is usually weak in the same direction that spine stability is poor. When hip flexion strength is weak, we see spine problems associated with poor anterior or flexion stability [Chris’s note: this is why we are looking at active flexion]. When hip extension is weak, there will be spine problems associated with poor posterior or extension stability [Chris’s note: why that all matters for the hinge].”
Regardless of the “why,” it all comes back to the cost of doing business. If someone cannot pass the ASLR with a 2L/2R, or better, we have to understand there is a potential negative cost to doing business with regards to loaded, full range of motion hinging.
What’s our approach?
Work on hip mobility, core stability, and retraining the hinge pattern. Progressively work to full range of motion loaded hinging as we clear the screen.
He nailed it with some great references from Movement-Gray Cook’s timeless book about breaking down how we look at, well, movement.
I took Chris’ answer and broke it down a little further.
Todd’s Answer:
Good question, man. I’m going to jump in and add some stuff onto Chris’ explanation. So the ASLR looks at hip dissociation. Can one hip remain in extension while the other his flexed. Vice versa, can one hip flex well while the other hip is in extension.
It’s done on the ground because that’s where gravity will have the least effect on the hips and we can purely determine whether or not the hips move well independently of each other. Put someone on their feet and ask them to hinge, or move at the hips, and we have a ton more shit to worry about. Do they have good stability/mobility in their feet and ankles? What about the mobility/stability of their spinal joints? Think of all the joints you just described-do you think if one of those is fucked up you’ll be able to purely determine how well someone’s hips move? Nah, dawg, nah.
Putting someone on the ground eliminates all of the potential influence of other joints and allows to just evaluate how well the hips and core are working in unison.
Now, if in this environment, that’s purely hip movement, someone can’t maintain good hip extension while flexing the contralateral hip, it tells us that they most likely don’t have the stability to hinge well on their feet. On the other side of the coin, if someone can’t flex their hip well while lying on the floor, there’s a good bet that this lack of movement capacity is going to effect them on their feet.
This also allows us to evaluate asymmetries from left to right. Sometimes poor hinging range of motion isn’t pure lack of skill or lack of mobility. Sometimes the brain puts the breaks on movement because it feels unsafe because adjacent joints aren’t functioning in unison.
The ASLR allows us to evaluate the raw materials that make up the hinge before putting someone into a hinge. If someone doesn’t have the hip movement to pass the ASLR, it’s likely that they aren’t going to have what they need to hinge well on their feet.
Here’s a quick summary.
The ASLR is a raw materials test-does a person have the hip/core strength and stability to hinge well? Can they synchronize core stability with hip mobility in the least threatening of positions? If not, it’s likely that they can’t do it when the full threat of gravity is bearing down on them.

