Dr. Joel Seedman, Ph.D.
Sissy squats are an old-school bodybuilding quad isolation exercise popularized decades ago by the legend himself Arnold Schwarzenegger. Over the past several years they’ve gained even greater popularity in mainstream fitness and bodybuilding settings as many folks believe they’re an effective quadriceps and thigh builder. Additionally, we’re seeing more recommendations and demonstrations of the sissy squat with individuals using extreme range of motion at the knee joint, far greater than what Arnold and his bodybuilding comrades used several decades ago. Read more about proper squat mechanics and range of motion here.
Although the sissy squat is a movement I used to periodically incorporate into my own workouts as well as those of my clients, I soon realized that there were far superior options that not only blasted the quadriceps more effectively but also spared the knees. With that said, here are my top 12 go-to substitutes for sissy squats.
Smith Machine Forward Leaning Squats on Toes
Perhaps one of the most simple, user friendly, and easy-to-access quad dominant squat variations is this forward leaning smith machine squat on the toes as shown here by my awesome client Leslie Petch.
Simply lean into the smith machine bar with your body at about a 20-30 degree forward angle, then perform squats while staying tall on the balls of your feet. Also, big shoutout to Leslie for coming up with this ingenious and incredibly effective movement. Got to love it when your clients create brilliant moves such as these. Learn more about my favorite smith machine moves here.
The great thing about this smith machine squat variation is that it can be modified to be more sport specific & power based. Here’s a variation my client & fellow PhD candidate Ben Lai developed.
Essentially, the smith machine allows mid rep modification by changing positions so the concentric explosive phase mimics forward leaning acceleration-based movement while the eccentric represents more of a traditional deceleration & impact position (putting the breaks on).
Notice Ben uses 90 degree eccentric isometrics. Going past 90 would not only compromise power & torque but it would place unnecessary strain on the joints & connective tissue while diminishing activation of the primary muscles. Simply, there’s rarely if ever a reason to go past 90 on any squat unless you’re training for competitive Olympic weightlifting or powerlifting. In such scenarios it would still be very smart to consistently include 90 deg squats in your training as they’re the most therapeutic & effective for building functional strength & hypertrophy.
In fact more & power powerlifters (i.e. box squat) & even Olympic weightlifters (Ilya Ilyan) are starting to do this as they’re saving extreme deeper positions for competition or pre-comp phases since these positions tend to break the body down while providing no additional benefit over 90. This principles of 90 degree joint angles will be applied to all the following movements as well.
Landmine Forward Leaning Squats on Toes
Because of the angular force vectors involved in the landmine set up the athlete is able to lean into the landmine and angle their body in such a way that allows them to shift onto their toes and have significant anterior knee drift all while performing a functional squat that’s highly sport specific.
These also blast the quads while being very knee friendly. Although they can be performed on a simple landmine station with the goblet setup, using the Purmotion attachments such as the Wishbone allows for greater overload and isolation of the lower body musculature. Read more about Purmotion Equipment here.
Purmotion Skier Forward Leaning Squats on Toes
The skier forward leaning squat using a different attachment from Purmotion is a great quad dominant and sport specific squat movement that not only mimics acceleration positions used in athletics, they also blast the quads while sparing the knees.
If you want to add additional tension to the quads try stopping the movement a few inches short of lockout as the constant tension and metabolic stress to the quads will be through the roof. As an added bonus the position literally forces the lifter to have perfect posture, pinning their shoulders down and back while maintaining a neutral spine with perfect 90 degree joint angles at the hips and knees.
Overhead Barbell Wall Squats
The overhead barbell wall squat is not only a great full body squatting variation, it’s also one of the most comfortable, user friendly, and natural feeling ways to perform overhead squats as the forward torso lean makes it much more conducive for maintaining optimal body mechanics in the overhead position.
It’s also a great postural exercise that provides a full body stretch from head to toe as the lifter experiences natural elongation throughout their thoracic spine as well as their thighs and hips.
Overhead Single Leg Barbell Wall Squats
If you’re looking to amp up the quad isolation factor and really feel some major tension in the quadriceps, try performing the overhead wall squat from a single leg position.
Besides requiring significant stabilization and full body motor control, this allows the user to blast the thighs while using relatively lighter loads. Read more about single leg squats here.
Overhead Barbell Wall Squats with Constant Tension
If the single leg variation of the overhead wall squat is a bit too tricky for you but you’re still looking for that insane quad pump, look no further than the constant tension protocol as Leslie shows here.
Simply stay in the bottom half of the movement throughout the set as this creates enormous mechanical tension and metabolic stress on the quads. In fact most of the squatting exercises shown in this article can employ this method for further quadriceps isolation and growth.
Squats with Heels Elevated
The heels elevated squat is one of the most classic quad-dominant modifications of the squat that lifters have been using for decades. Rather than attempting to unnaturally shift onto your toes when squatting and forcing excessive anterior knee drift, elevating the heels 1-2 inches allows the lifter to still drive through their entire foot with perfectly vertical force vectors all while placing slightly greater stress on the quadriceps.
With that said, there are 2 very common mistakes lifters make when performing these.
First, they use excessive range of motion and try to get as deep as possible. While it is in fact easier and more comfortable to go ATG on heel-elevated squats in comparison to traditional squats, the optimal ROM for these is 90 degree just like any other squat variation.
The second common mistake is allowing extreme forward knee drift and not placing enough weight back onto the heels. Focus on placing equal tension through the whole foot and sitting into the hips and knees equally as you would on any other squat. Simply allow the heel elevation to take care of any extra quad activation by creating a slight yet natural anterior knee drift. In other words, don’t force the knees past the toes unnecessarily but instead allow it to occur naturally and semi-subtly.
Reverse Wall Ball Hack Squats
The reverse wall ball hack squat is a simple yet effective quad-dominant squat variation that allows a very natural forward torso lean into the ball. It also allows for very natural loading as the lifter simply holds kettlebells or dumbbells in their hands to produce greater tension to the targeted musculature.
Because of the instability created by the ball these also require the lifter to slow the movement down and use smooth and controlled body mechanics all of which blast the thighs while instilling optimal biomechanics.
Makeshift Jammer Zercher Squats
The makeshift jammer setup is not only great for performing a variety of functional upper body pressing exercises it’s also incredibly versatile and conducive for sport specific forward leaning squats. Simply anchor the bar into your arms like a standard Zercher squat, walk forward a few feet, stand on the balls of your feet, lean into the bar with your body angled 20-30 degrees forward, then perform 90 degree eccentric isometric squats.
On a side note I recommend setting these and all of the makeshift jammer squats so that the rings or suspension system is slightly lower than it would be for the presses. For instance on the presses I recommend having the rings set up so that the bar is roughly 2-3 feet above floor height. For the squats I recommend setting the bar and rings 12-18 inches above floor height as this provides the perfect combination of horizontal and vertical force vectors to crush your legs while providing the most natural motion. Read more about Zercher squats here.
Makeshift Jammer Single Leg Zercher Squats
The same setup can also be used to perform single leg squats and split squat variations.
These can employ 90 degree hip flexion with forward knee drive in the finishing concentric position which not only produces even greater tension on the targeted musculature but also provides incredibly sport specific movements that transfer exceptionally well to sprinting mechanics and acceleration-based positions.
Makeshift Jammer Skier Squats
The makeshift jammer setup can also be combined with skier squats as Leslie shows here. I also nicknamed these cannon squats as it should mimic the position of someone being shot out of a cannon.
Similar to the Purmotion skier squats I highlighted above, these not only provide a great squat position that’s incredibly athletic-based and sport specific, they also do wonders for enhancing postural mechanics and spinal alignment.
Trap Bar Sprinter Variations
Here’s another great way to use angled force vectors that allows proper application of knees over the toes with heels elevated.
Another benefit of these trap bar sprinter variations is that the lifter must learn to calibrate their force vectors not only with the anterior knee shift & center of mass adjustments, but also with the degree they shift to their toes. Too much shift forward or back & the lifter will lose their balance.
This is very valuable for teaching athletes to control their center or mass & body mechanics particularly under sport-specific conditions where they must calibrate how little or how much their body should shift forward or backward for optimal performance.
These also improve foot, ankle, & calve stiffness which is critical for sports performance, explosive power, & Achilles health. Simply we want the foot & ankle complex to function like coiled springs which they must do during these squats.
Additionally, the quads and calves often work synergistically on the playing field as it does in these squats making them even more transferable to athletic scenarios.
Allowing the lifter to elevate their heels under a block or wedge while acceptable, eliminates or compromises these previous aforementioned benefits.
Pre Exhaustion Leg Extensions Prior To Squats
If you're looking for an absolutely brutal superset to devastate your quads try performing an intense set of leg extensions prior to any squat movement as my client Ben Lai shows here. Performing these prior to the squat ensures you’ve pre-exhausted the quads thoroughly which causes them to fatigue and fail before the glutes, hips, upper body, low back, or core does. In other words, it helps isolate the quads more so while still adhering to proper biomechanics during the squats.
The pre-exhaustion technique using leg extensions before squats is an old school bodybuilding technique that has been used for decades by some of the best bodybuilders in the world. Just make sure to use smooth mechanics on the leg extensions and eliminate momentum in order to avoid placing too much stress to the knees.
The Problem with Sissy Squats
It doesn’t take an expert in biomechanics and functional anatomy to realize that the stress placed on the knee joint during sissy squats is less than ideal as the weight is shifted excessively and unnecessarily forward into the knee joint.
Yes, some folks who’ve been blessed with genetically resilient knee joints can get away with these. However, just because an individual can get away with a movement doesn’t mean it’s ideal or optimal. If, in fact, dysfunctional and aberrant mechanics are employed during a movement (which one could argue is the case with the sissy squat), eventually there will be consequences.
As I’ve stated multiple times in various posts “Poor mechanics is like smoking. It can take anywhere from months to decades before the consequences are felt. Eventually it does affect your health and quality of life. It’s just a matter of time.” Read more about Pain Science & Body Mechanics here.
So yes, generally speaking I don’t recommend consistently performing traditional or even modern day variations of the sissy squat movement as I believe there are far safer and more effective movements. Additionally, when it comes to understanding functional movement and optimal biomechanics for the human body it could be argued that the sissy squat is highly dysfunctional as in no way shape or form does it represents a movement we would ever do in everyday life or sports particularly under perfectly vertical force scenarios. In fact, if we were to observe an athlete assume such a position during sports or athletic events on a consistent basis we would consider that very poor biomechanics and a very un-athletic movement in need of a serious overhaul.
The Truth About Knees Over Toes
One of the biggest debates currently trending in the fitness industry is the question of whether allowing the knees to move in front of the toes is dangerous or not. In reality, there’s nothing wrong with the knees going past the toes in terms of anterior knee drift with the caveat being that the force vectors of the body must match the incoming force vectors of the movement/environment.
Simply, it’s not so much about knee position (i.e. knees past toes) as it is a question of where the force vectors are coming from. For instance, all of the squat variations shown in this article, performed on the toes or the balls of the feet, include both vertical and horizontal force vectors (i.e. angular forces), similar to going down the stairs or during certain forward athletic movements (i.e. acceleration). In such scenarios the knees will, and oftentimes should, move past the toes. The key here is to match up our force vectors with the incoming forces.
If you were to take snapshots of any of the squats shown in this article, rotate the image 30-45 degrees, it would look nearly identical to a traditional squat as they would illustrate the same joint mechanics and positions as traditional 90-degree squats, with proper joint stacking of the ankles, knees, and hips. And although the lifter would be on their toes their ankle or shin angle would be no different than a traditional squat (i.e. the degree of dorsiflexion would be the same). Instead, they would have shifted every component of the squat equally to match the incoming force vectors. In such instances there would be relatively equal joint stress across the hips and knees while simultaneously placing greater tension on the muscles of the quadriceps.
In contrast, when we allow the knees to move past the toes during a traditional squat where there’s only vertical force vectors, we’re now producing a horizontal force vector against a primarily vertical force, which represents a mismatch of force vectors. This not only compromises force production and absorption, it also places undue strain on the joints and connective tissue as the muscles are in a biomechanically disadvantageous position to absorb and produce force. The same is true of a lunge or split squat.
With that said attempting to sit back into the heels and minimize anterior knee drift by not allowing the knees to travel forward on any of the squats shown in this article not only feels very unnatural but it actually places even more stress on the knees. That’s right, trying to inhibit the knees from going forward during movements such as those shown in this article is actually just as dangerous and counterproductive as attempting to produce excessive anterior knee drift during movements that involve perfectly vertical force vectors such as traditional squats.
In fact, I can tell you from personal experience having experimented with the movements I highlight in this article, attempting to eliminate anterior knee drift and inhibiting the knees from traveling past the toes feels miserable on the knees not to mention very unnatural and dysfunctional. Therefore, it is quite obvious that the question of “knees over toes” being good or bad all comes down to the context and is predicated on whether or not there is a matching or mismatching of force vectors.
When force vectors are matched, performing a movement with the knees traveling significantly past the toes and shifting weight to the ball of the foot is not only extremely functional and transferable to athletic performance, it’s also a tremendous quad and thigh builder. It’s also a great way to strengthen the connective tissue around the knees while simultaneously ensuring the muscles are doing their job of absorbing force in the most effective and efficient manner.
In contrast, attempting to force the knees past the toes when force vectors are mismatched, is not only a subpar strength and hypertrophy stimulus for the quads, or any muscle, it’s potentially dangerous on the knee joints not to mention it reinforces dysfunctional movement patterns into the CNS that are likely to transfer to other movements and ultimately compromise athletic performance and quality of movement. Read more in my book MOVEMENT REDEFINED.
If You Insist
If you insist on performing sissy squats and feel they work well for your body there are several recommendations I would make.
1. Don’t go beyond 90 degree joint angles at the knee.
2. Stop performing them if you feel any pain or discomfort.
3. Minimize the volume and simply use 1-2 sets as a quad finisher.
What About the Sissy Squat Machine
As I’m not a fan of traditional sissy squats, it may come as a shock to those reading this that I actually don’t mind the sissy squat machine as it places the body particularly the hips and knees into a much more biomechanically sound position with far less stress on the knee joint. In fact it’s quite feasible and natural to perform this movement with 90 degree joint angles at both the hip and knee joint which is ideal. So if you’re going to perform sissy squats, this is definitely the preferable and optimal method.
Stop Contorting & Manipulating your Body Mechanics
A common trend in the fitness industry, as is the case with sissy squats, is to unnaturally alter the angles and mechanics of the movement and body to isolate a particular muscle group (i.e. shifting to the toes and knees to isolate the quadriceps). Unfortunately, altering natural body mechanics is a great way to promote dysfunctional movement patterns and destroy the joints. This is something I refer to as "erroneous muscle targeting" as the lifter has to abandon proper activation patterns in hopes of isolating specific muscles.
A properly performed squat should involve lower body centration with equal stress across the joints and involved musculature rather than isolating a specific area. Besides saving your joints, this places the lifter into the strongest position to handle the most weight for the most reps, ultimately maximizing muscle growth.
If the goal is to target a specific muscle group, there are more efficient methods that can be employed as I’ve highlighted. Rather than butchering your body's natural mechanics and reinforcing faulty movement, try maintaining ideal mechanics and technique for that movement. As shown in this article, holding firm to such fundamental principles of kinesiology is not only critical but quite easy as shown with the different variations I laid out.
Additionally, pre-exhaustion methods can also be employed to further emphasize quadriceps development while adhering to ideal bod mechanics. For example, if the goal is to hit the quadriceps more effectively on squats, perform an isolation movement such as leg extensions or any of the other squat variations shown here immediately prior to hitting a traditional set of squats. This will cause the quadriceps to fatigue and fail before the hips, glutes, or low back musculature give out.
More importantly, you'll have emphasized a particular muscle group while keeping your movement patterns intact rather than wrecking your natural body mechanics with a mutated variation of the exercise. Read more about the consequences of faulty body mechanics here.
Rules for Superior Sissy Squat Substitutes
1. Force vectors must match up. If there are no significant horizontal force vectors involved then the knees should not drift too far beyond the toes and most of the weight should be maintained on the entire foot including the heel throughout the motion with the exception of terminal knee extension during explosive dynamic movements (i.e. leaving the ground during a jump).
2. The movement should mimic the same or similar positions we would observe in sports or everyday life. Simply, it should both feel and look natural, not contorted or forced.
3. Forces during squats should be centrated and distributed across as many of the involved joints as possible rather than attempting to overly isolate one particular joint. In other words, attempting to minimize movement at the hip joint in order to isolate the knee joint would be an example of poor joint centration as the individual would not be distributing forces as equally as they should between the hip and knee joint but instead would be attempting to over-stress the knee joint.
4. Similar to the above point, the hip and knee joint should move at approximately equal rates and the joint angles should be relatively similar to each other throughout the movement. Additionally, the torso and tibia should be almost perfectly parallel to each other as this is simply another indication that the forces are being transmitted equally across the knee and hip joints.
5. The joint angles at both the hips and knees should be approximately 90 degree joint angles in the bottom stretched position.
6. The mediolateral alignment of the joints should be stacked such that if you were viewing the movements from the front position, the feet, ankles, knees, and hips, would be perfectly in-line with each other, forming 2 stacked columns rather than allowing them to externally rotate, flare out, or cave in.
7. The lifter should employ eccentric isometrics on most of the movements as this will allow them to fine-tune their body mechanics and optimize the quality of the movement while maximizing their proprioceptive feedback and sense of feel. Read more about eccentric isometrics in my book MOVEMENT REDEFINED.
