Forward Lunges: 4.6x Body Weight on Knees!
54sShocking stat about knee stress makes viewers question their lunge form and want to learn the fix.
▶ Play Clip"Solid content that delivers detailed biomechanical insights, but the hyperbolic 'SAVE A FRIEND' oversells a bit."
This video explains why reverse lunges are superior to forward lunges for knee health and muscle targeting, providing detailed biomechanical reasoning and form cues. It covers foot placement, upper body positioning, torso lean, loading, and depth to help viewers perfect their reverse lunge technique.
Forward lunges place 4.6 times body weight on the patellofemoral joint and patellar tendon, with high force rate that can exceed knee capacity.
Stepping backwards keeps the front foot on the ground, eliminating impact and reducing knee stress compared to forward lunges.
Forward lunges often cause hip sliding back during push-off; reverse lunges naturally allow straight up and full hip extension.
Step back and out to at least shoulder width for a stable base, avoiding narrow stance that turns it into a balance test.
Reach back with your toe; when it contacts the ground, go straight down from there for proper spacing.
Rotate your upper body slightly toward the lunging leg on each step to stabilize the pelvis and prevent balance issues.
Upright torso targets quads; leaning forward (hinge at waist) loads glutes and hamstrings more effectively.
For posterior chain focus, use dumbbells as they allow forward lean; for quad focus, use barbell on back or rack position with upright torso.
Lower until back knee lightly touches the ground (kiss, not bang). Ankle limitations may prevent full depth; adjust as needed.
By switching to reverse lunges and applying the form cues—proper foot placement, upper body rotation, torso lean, and depth control—you can build strong legs while minimizing knee stress.
What is the force on the knee during a forward lunge?
4.6 times body weight.
00:30
How does reverse lunge reduce knee stress?
The front foot stays on the ground, eliminating impact from stepping.
00:56
What foot placement width is recommended for reverse lunges?
At least shoulder width.
02:07
How do you determine step length in a reverse lunge?
Reach back with your toe; when it contacts the ground, go straight down.
02:50
What does rotating the upper body during a lunge do?
It stabilizes the pelvis and provides additional stability.
03:29
Which muscles are targeted by an upright torso in a reverse lunge?
Quads (anterior chain).
04:12
Which muscles are targeted by leaning forward in a reverse lunge?
Glutes and hamstrings (posterior chain).
04:38
What equipment is best for posterior chain-focused reverse lunges?
Dumbbells, because they allow independent arm movement while leaning forward.
05:46
What equipment works for quad-focused reverse lunges?
Barbell on back or rack position (weight held against chest).
06:11
Is it okay for the back knee to touch the ground during a reverse lunge?
Yes, light contact (kiss) is fine and indicates full depth.
06:50
Reverse Lunge Reduces Patellar Stress
Explains key biomechanical advantage of reverse lunges over forward lunges for knee health.
00:30Natural Hip Extension in Reverse Lunge
Shows how reverse lunges avoid compensation and promote proper mechanics.
01:09Wide Base for Stability
Emphasizes a simple adjustment that greatly improves balance and muscle focus.
02:07Upper Body Rotation for Pelvic Stability
A subtle cue that enhances control and prevents common form faults.
03:29Torso Lean Alters Muscle Focus
Demonstrates how a small change in torso angle completely shifts which muscles are worked.
04:12Loading Choice Depends on Body Position
Connects equipment selection to desired muscle targeting, avoiding inefficient or risky loading.
05:18[00:01] don't see someone doing my favorite leg exercise, the lunge. And that makes my heart sink. The only problem is, they're [ __ ] it up. we're lunging. And of the two popular directions that we can lunge in, forward
[00:15] or backward, [music] the most popular happens to be the most stressful to your forward, [music] we're placing a lot of undue stress on that patellofemoral patellar tendon, that doesn't have to be there [music] if we just simply were to
[00:30] direct our step backwards. And the issue is not just how much force, which is actually 4.6 times your body weight, but the rate that we apply it. When we step, hits the ground. And when it does, we have to quickly be able to adapt to that
[00:44] stress. So, even if you are able to handle 4.6 times your body weight, like a lot of knees can, the speed that we apply that force can sometimes be more than you can handle, which causes the knee pain. So, if we step backwards,
[00:56] that front leg stays in contact with the ground. It's not stepping up and applying itself down every single time. It's already there, which gives us a lot pain. The next thing though is also, what is the effect on the legs that
[01:09] you're trying to grow? When we step, the issue is not just how we land, but how we push out of the lunge from this position, we oftentimes compensate [music] instantly. We slide the hips back and then we stand up. Rather than
[01:24] straight up out of there and step backwards. When we do the reverse lunge, that all happens naturally. We step back, the leg goes straight down, we to [music] full hip extension. So, biomechanically, you're doing the lunge
[01:39] properly. Now, if you wanted to step forward, [music] you have to at least continue in a walking direction. You'll see The Rock doing this variation here, [music] having to try to compensate backwards, you just simply rise up and
[01:53] step through and take your next step. That will help fix a lot of those doesn't take away that negative effect of the stresses on the knee joint. You with the step direction in place, the most important next thing for you to
[02:07] focus on is where you're specifically putting that [music] back foot. Every for you to step to. And what we want to do is not turn the lunge into a field sobriety test by stepping too close together. If your feet stay in line with
[02:22] primary focus rather than building your legs with this fantastic exercise. Instead, what I want you to do is step back and out. Get at least two shoulder width or outside of shoulder width with your step to give yourself a wider base
[02:37] of support and provide the balance and stability that you need to focus on just building up your legs rather than maintaining balance. As far as how far back you should go, that's determined by [music] the length of your leg, which
[02:50] can easily be fixed by just using your toe as a landmark. As I [music] step back, reach with your toe. Once your toe makes contact with the ground, that's as straight down from there. Now, that distance is going to be different for
[03:03] everyone that does the exercise, [music] but as long as you're using your toe as the guideline, it makes contact, you go straight down, that width is properly spaced, and you've got GPS-like accuracy in terms of the foot placement to make
[03:15] we have to think about what's going on with your upper body. Cuz even though this is a lower body exercise, the position of our upper body will body exercise. [music] Cuz you have a great opportunity to screw your body
[03:29] into place and provide additional stability by just simply rotating your you do the exercise. [music] So, what I'm saying is every time I step back, I want to turn my body just a little bit from my shoulders in the direction of
[03:43] actually create a little bit of internal rotation at the hip, but more so with going to provide a little more stability and locking of the pelvis in place so [music] could derail the success of the movement. Remember, every time I step
[03:59] back, I get a little turn from the upper body in the direction of that lunging easy. Now, the position of the torso doesn't just matter in terms of how rotated your shoulders are, but also how forward or
[04:12] when you do the exercise because it determines which muscles you're actually focusing on. So, if I do an upright [music] reverse lunge, then most of the focus is going to be directed right here at the quads, [music] the anterior
[04:25] Because when I come out of it, I maintain this upright position much like I would during a front squat that targets the same muscles. If instead I were to lean forward a little bit by hinging at the waist, what this does is
[04:38] lunge. We're looking like [music] we're position here, well, this is going to load up that backside glute and hamstring more effectively. So, if I do it from this side, you can see that by
[04:51] yourself just by doing this, you get a lot more loading posteriorly, and this is the focus of the exercise itself. So, I can do the exercise either way, just be aware of the fact that changing your position, be it upright or leaning
[05:06] dramatically change the focus of the muscles that you're trying to target Which brings us to the next consideration here, which is how you load the exercise. And that has a lot to do with what we just covered, the body
[05:18] Because if you were to try to do, let's say, a posterior chain focus version of and you were going to do it with some type of object, either a kettlebell or a rack position here, then leaning forward is going to become very, very difficult.
[05:33] weight close enough to your chest to [music] avoid [ __ ] up your back beyond just messing up the exercise. So, what we do instead is choose [music] the implement that works best. For anything posterior here, you're best off going to
[05:46] be holding a pair of dumbbells because no matter what I do, my arms are going to be independent of the rest of my body. So, I can tilt my torso forward but not have that affected by the position of the dumbbells that hangs
[05:58] do want to do this even forward or backward and you want to make sure you're focusing more on your quads, then the upright position would allow you to put the barbell on your back or the rack position with the weight held up here
[06:11] against your chest. Either one would work but mostly for that anterior focused upright body position. But how you apply the load to your body is up to the position of your body while you do it.
[06:23] >> Which brings us to the question of depth. Hey Jessie, how deep is good >> I hope 2 and 1/2 inches. >> Poor guy. Listen, the depth is going to it's going to be determined by the position of that back knee in relation
[06:37] to the ground. Or if you have orthopedic limitations either in your hips or most often in your calf or Achilles, then it's going to be determined by how far you can go based on how tight you actually [music] are. First of all, the
[06:50] knee can actually make contact with the ground. I hear [music] all the time that contact with the ground. It's not supposed to make contact with the ground hard. You never want to direct that kind of force into your knee unnecessarily,
[07:02] but it can kiss the ground cuz it gives you the idea that you know you actually got down all the way to full depth. This would be full depth. If instead you had limitations at the ankle, then what would happen is as I go back, I run out
[07:16] of dorsiflexion at the ankle there and I'm stuck. So, my only option at that point is to pitch forward to give myself the appearance of actually getting shift the focus to the posterior chain away from the quads. Or I'm just going
[07:31] continue. And again, I mentioned the rock before, [music] he had an Achilles limitation you see here, but there's nothing incorrect about that lunge. It's just working with what he had. That being said, I love the lunge, and if you
[07:45] you're going to improve the way you're doing yours. If you want to do it, I total body workout that I'm giving to you for free just by visiting athleanx.com/tbfree
[07:57] guys, if you haven't done so, head to athleanx.com, get the Athlean-X training find the program that's right for you and your goals. We have complete lines subscribe, turn on your notifications so you never miss a video I'm putting out.
[08:10] Try this out. Let me know if it helped you out. See you.
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