There are many squat variations that one can add to their training program. Box, Front & Bulgarian squats are three particularly useful versions of the exercise. The back squat is great for individuals looking to work on sticking points, learning proper depth and training the concentric portion of their squat (due to removal of stretch shortening cycle). Front squats are beneficial for those involved with Olympic weightlifting and may benefit individuals with knee issues. Last, but not least, Bulgarian squats are a very effective single leg exercise that has great carryover to sport activity.

Gotta Love Them Squats

Figure 1. The Front Squat performed with crossed arm form.¹

Squats, Squats, Squats… Regardless of your end goal (powerlifting, bodybuilding, ball/speed/team sport or simply improved body composition & health), the squat can be used as an integral part of your training routine. Here at CasePerformance, we love squats so much that we’ve already written 3 articles on the subject. In Free Weight Squats vs. Smith Squat Machines we discussed the superiority of performing the squat using with free weights vs. a machine based version. In Mechanics of Squatting we examined recently completed research studies which focused on the effects of speed of movement, muscle activation patterns and similar issues. Next, we learned about common errors of the basic squat motion and how to correct them in Squatology 101.

After reading through the aforementioned articles, we’re confident that you’re well versed in the basic squatting motion and have been applying them to your training program. Thus, in this article, Squatology 202, we’re going to take it to the next level, focusing on the various types of squats one can do and how they can be implemented into your training routine.

The Box Squat

Figure 2 The Box Squat.

The box squat is a popular version of the back squat, particularly among powerlifters and strongman competitors. The fundamental purpose of the box squat is to load the box carefully prior to exploding out of the box with the hips. This leads to increased speed and greater activation of the hip/quad musculature. Additionally, the box squat allows one to work a particular range of motion within their specific “sticking point”.

Often associated with the box squat is the ‘rocking box squat.’ This method has the weight leaving the feet briefly as one rocks back (very slightly) and then returning back on to the feet before driving hard up off the box.

Performing the Lift

There are many different boxes one can use to perform the lift including an actual box of wood/metal (similar to low plyometric jump boxess), or even a stack of bumper plates. Regardless of what you use as a “box”, the key thing is that it’s a non-slip surface or platform. Once selected, the box is set up behind the lifter, behind their normal foot position.

During the box squat, one’s stance is usually the same or possibly even wider than a back squat in order to allow greater contribution from the adductor muscle group during the concentric portion of the lift (ie- ascension off the box). Although variation and inter-individual variability exists, the heels should be very close to the front edge of any box. With the box squat, one should engage and focus on “getting the hips back”/ “sitting back with the hips” and shoving the knees out. They should also maintain a slight forward lean to counterbalance the “hips back” position. One of the MAJOR PROBLEMS I see in individuals performing the box squat, especially those untrained, is that they DO NOT approach the box with a slow decent (eccentric phase). Instead, they rapidly descend, “crashing” down on the box.

As beneficial as box squats are, it’s important to remember they are an advanced exercise; the risk of injury increases substantially in those who are not physically prepared or properly coached in the exercise. Specifically, the risk for spinal compression between the box and the bar is high and should not be used in untrained individuals.

Benefits & Application of the Box Squat

Benefits

There are many advantages to box squatting:

• 1) By pausing on the box, the stretch shortening cycle is removed from the lift. Therefore, you have to rely entirely on your muscles to move the load vs. relying partially on the elastic “spring” provided by their connective tissue. In addition, from an athletic standpoint, many movements rely entirely on concentric only contractions. Examples include an offensive lineman exploding out of their stance in a football game or a track athlete shooting out of the blocks at the start of the race.

• 2) The box squat allows you to sit back onto the box to a point where your shins are past perpendicular to the floor. This places all the stress on the squatting muscles (hips, glutes, lower back and hamstrings.) When you can increase the stress on these muscles and lower the stress on the quads, you’ll be ready to see your squat poundage’s increase.

• 3) Restoration is another major advantage of box squatting. You can train more often on a box vs. free squatting. According to Louie Simmons, many powerlifters have used box squats three times a week. However, if you’re new to box squats, I recommend you do them once per week.

• 4) When box squatting, one never have to guess the actual depth. It’ll always be the same. Keep in mind, when most people begin adding weight to the bar, their squat depth is unconsciously lower (ie – Their squats get higher and higher.) Pay close attention to this in any gym, trainees look good with the light weight, but lose squat depth as the weight increases over consecutive sets. With box squats, you’ll always go low enough.

• 5) Finally, the box squat can be used to teach proper back squatting technique, perhaps in those who may have skeletal muscle or range of motion limitations due to injury, etc. Many times for the intermediate or beginning squatter, the hamstrings have not been fully developed, thus increasing the susceptibility into falling over backward, because they are not yet capable of counteracting the force with the glutes and hams as well as not placing the entire force throughout the whole foot. Teaching athletes how to free squat properly takes months, and years to perfect, but can be learned more effectively and quickly using the box squat as an adjunct exercise. However, as previously mentioned, due to high risk of injury in untrained individuals, this lift DEMANDS proper coaching!

Application

The box squat can be used for a variety of reps, sets, and various box heights depending on the desired training effect. Individuals should know that the loads used will differ among the various box heights. Specifically, with the lower the box, the weights used are typically similar to those loads used during the regular back squat, if not slightly lighter. The higher the box, the more weight can be used and can exceed the 1RM of a normal back squat due to the large decrease in the range of motion.

Most sets and reps scheme are used in the 2-5 rep range, although it can be completed using additional reps. Most box squats are used for explosive and speed purposes, in addition to working a particular range of motion. Here is a suggested 4-week block:

• Week 1: 8-10 sets of 2-3 reps @ 65%

• Week 2: 8-10 sets of 2-3 reps @ 70%

• Week 3: 8-10 sets of 2-3 reps @ 73%

• Week 4: 8-10 sets of 2-3 reps @ 75%

Allow 60 second rests between sets.

A research note regarding box squats…

According to McBride et al, eight resistance trained men performed 1 repetition of squats and box squats using 60, 70, and 80% of their 1RM in a randomized fashion¹. Subjects completed the movement while standing on a force plate and with 2 linear position transducers attached to the bar. Force and velocity were used to calculate power. Peak force and peak power were determined from the force–time and power–time curves during the concentric phase of the lift. Muscle activity was recorded from the vastus lateralis, vastus medialis, biceps femoris, and longissimus (via EMG). Results indicated that peak force and peak power are similar between the squat and box squat. However, during the 70% of 1RM trials, the squat resulted in a significantly lower peak force in comparison to the box squat. In addition, during the 80% of 1RM trials, the squat resulted in significantly lower peak power in comparison to the box squat. Muscle activity was generally higher during the squat in comparison to the box squat. This is primarily due to a larger range/full range of motion of the back squat compared to the box squat.

The Front Squat

Figure 3. The Front Squat performed with Olympic style arm position

The front squat is an outstanding variation of the back squat. As the name implies, the main difference is that the lift is performed with the barbell resting across the FRONT of the shoulders, in front of the neck. It is a variation that maximally stresses the quadriceps and, from a mechanical perspective, can be very difficult to perform.

Performing the lift

In comparison to the back squat, the front squat places less emphasis on the hips due to the difference in bar position. As aforementioned, the bar is placed on the anterior deltoids with the elbows up and the hands trapping the bar in place (Figure 3). Considering this major difference, the back angle for the front squat is near vertical, compared to the back squat, which is more horizontal (Figure 4). The upright position allows the bar over the feet and keeps it from falling off the anterior deltoids (shoulders). Quite often, front squats are missed when the weight is simply too heavy for the lifter to maintain this upright back position. As a result, the bar falls forward, along with the lifter.

Figure 4. Back angle in back vs. front squat. As seen in picture, one’s back is more vertical while performing a front squat (left image) vs back squat.

Considering the near vertical angle of the low back in the front squat, the upper back is stressed to a higher degree (vs, back squat) because the load it is holding up is farther away from the hips. For those familiar with physics, this is analogous to biomechanical force arm, or moment arm – the perpendicular distance from the line of action to the axis of rotation. In other words, the bar is further away from the axis of rotation (ie – hips), thus increasing the force arm, presenting a mechanical challenge to the lifter and musculature that maintains thoracic extension. That said, due to the lighter loads used, many people may find it more comfortable and less difficult than the back squat²³.

Since the front squat has the hips directly under the bar, one should focus on “driving up” the chest, shoulders, and elbows during both the eccentric and concentric phases. This will assist with maintaining the vertical back which becomes especially when heavy loads are used. This is critically important as the position and drive is much different than the “hip drive” which is emphasized during the back squat (Please refer to Squatology 101). Acknowledging this difference between the two lifts is crucial. Therefore, I feel that the front squat should not be taught until the back squat has been mastered and technical error is minimal.

Let’s shift our focus and address the action of the knees. With the front squat, the knees are more forward at the bottom position compared to the back squat, producing a more acute knee angle. Due to the near vertical back position (which alters pelvic orientation), the hamstring origin and insertion become closer together. Therefore, the hamstrings ability to contribute force to the movement is compromised. The combination of knees forward and vertical back angle, places a significant stress and load on the quads after the initial hip extension while ascending out of “the hole”.

There is some evidence to indicate that the front squat may be healthier for the knees vs. the back squat. In a recent study completed by Gullett and colleagues, researchers had 15 healthy, experienced subjects complete both front and back squats at the same relative load (70% 1RM)². The front squat was as effective as the back squat in terms of overall muscle recruitment (please note glute maximus activity was not measured). However, there was significantly less compressive forces on the knee joint. The results suggest that front squats may be advantageous compared with back squats for individuals with knee problems such as meniscus tears, and for long-term joint health.

Benefits & Application of the Front Squat

There are many reasons as to why one can/should implement the front squat into their training routine. In my opinion, one of the greatest benefits in performing the front squat is its application and transfer to Olympic lifting, specifically the clean and jerk. The front squat position is most notable during the “catch” phase of the lift. In fact, USA Weightlifting guidelines (2011) promote the front squat among its 6 basic exercises and progressions⁴.

Basic Exercises

1). Front Squat

2). Power Clean- Mid thigh, Static, Dynamic

• Below Knee
• Power Clean

3). Behind the Neck Press- Clean Grip

4). Behind the Neck Press- Snatch Grip

5). Power Snatch Progressions

6). Back Squat

Sets & Reps

Sets and reps for the front can be used in several ways. However, it is recommended that sets and reps of 3-5 should be used (i.e. 4×5). This is based off the fact that the stabilization of the shoulder complex and core musculature give out sooner than the back and leg muscles when higher reps are used.

Bulgarian Split Squat

Figure 5. The start position of the Bulgarian squat.⁶

Single-leg training is one of the most versatile tools and variations to use among the lower body. Most often, single-leg training results in less back stress due to the reduced loads. Also, one of the best applications of single leg training is sport. Almost everything in sports in a split stance, or by pushing off one leg from a parallel stance; Thus it just makes sense to train both unilaterally and bilaterally in order to minimize dominant and non-dominate problems. One of the best single leg exercises one can do is the Bulgarian squat. For reference, you may see others may refer to it as the Bulgarian lunge, despite the fact it didn’t originate in Bulgaria and isn’t a lunge. You may also see it referenced as the Rear Foot Elevated Split Squat (RFESS).

Performing the Lift

The exercise starts similarly to a back squat, in that you position the bar on your shoulders in a squat rack, lift it off the supports, and walk back. Next, lift one foot and place it on the bench behind you (Figure 5). You want to rest the top of your foot on the bench, even though it may be uncomfortable if you’re used to doing this exercise with your toe on the bench with the ankle in a dorsiflexed position. Although performing the exercise with in this latter position may be easier with lighter loads, it is not possible to do so with heavier loads because the range of motion is longer, and your balance will be worse. In terms of elevating the back foot, an exercise bench works for most individuals. If the stretch in your quads and hip flexors of your elevated leg is too extreme or uncomfortable, switch to a slightly lower box or step.

Figure 6. The end position of the Bulgarian squat (prior to returning to the top).⁶

Ideally, the loaded leg should achieve a parallel depth with the non loaded knee close to touching the ground (Figure 6). To help achieve this, one can place a soft pad or mat on the floor under the rear knee, and tell clients/athletes to touch the pad with their knee on each rep. This creates consistent depth, and also allows protection of the knee from the hard surface. Similar to the back squat and front squat, core musculature should be tight and chest should be up. The core muscles are critically important in the Bulgarian squat, as the elevated rear foot may create undesirable back arch. For reference, the back should be at approximately the same angle as the shin (of the loaded leg) is with respect to the ground.

Benefits & Application of the Bulgarian Squat

Benefits

Bulgarian Squats has numerous benefits. For example, in novice trainees, it will improve balance, hip flexibility, as well as develop strength, and size. The lift is also beneficial for more advanced lifters as they can place a heavy load on their legs while minimizing spinal compression vs. completing the back squat, and perhaps front squat. Although very beneficial for novice & advanced lifters alike, I’d like to point out at this point that the Bulgarian Squat, is advanced progression, which should only be completed once an individual has mastered the split squat. A key element of progression from the floor to a bench is of course you can increase the range of motion, and stability within that new range of motion, which is one of many ways to make an exercise harder and more challenging, if used appropriately.

Application

Set and rep range can be varied, however, due to slight discomfort, very high reps should be used with caution. Thus, I recommend using 3-4 sets of 1-8 reps while performing Bulgarian Squats. Please note that this is the number of sets/reps that should be used for each leg. Also, if, while performing the lift, you find that one leg is considerably stronger than the other one, complete extra sets, etc, in order to bring the “lagging” leg up to the same level as the dominant leg.

Bottom Line

As we’ve discussed in this article there are many different types of squat exercises that one can perform. Each of which can benefit your training program. That said, be sure to do so under the supervision of someone experienced in the lifts as the box, front and Bulgarian squats are advanced exercises.

References

¹ McBride JM, Skinner JW, Schafer PC, Haines TL, Kirby TJ. Comparison of kinetic variables and muscle activity during a squat vs. a box squat. J Strength Cond Res. 2010 Dec;24(12):3195-9.

² A.A. Braidot, et al (2007). Biomechanics of Front and Back Squat Exercises. Journal of Physics

³ J.C Gullet, et al (2009). A Biomechanical Comparison of Back and Front Squats in Healthy Trained Individuals. Journal of Strength and Conditioning Research.

⁴ USAW Level 1 Sports Performance Coach Handbook

⁵ Image created by Everkinetic and is under creative commons licensure. Accessed November 5, 2011 from: http://everkinetic.com/exercise/front-squat

⁶ Image created by Everkinetic and is under creative commons licensure. Accessed November 5, 2011 from: http://everkinetic.com/exercise/one-leg-squat