The box squat is a variation of the standard squat that may or may not utilize additional resistance in the shape of a loaded barbell, though some exercisers simply choose to perform box squats with their own bodyweight alone.
It is generally performed for the purposes of inducing muscular hypertrophy in the glutes, hamstrings and quadriceps muscle groups of the legs in an explosive manner meant to target fast twitch muscle fibers specifically.
The box squat is a lower body compound movement of varying intensity and complexity, usually combined with other leg muscle group isolation exercises in order to induce a training stimulus that is considered quite effective at building up muscular power output and size.
In more specific terms, the box squat is a closed kinetic chain compound movement with a push type movement chain and a muscular activation pattern spanning practically every muscle group in the lower body, as well as the erector spinae, hip adductors and core stabilizers to a certain extent.
When performed as a bodyweight exercise, it primarily trains the muscles in a stabilizing capacity, as well as enhances the muscular endurance of all recruited muscle groups.
This is not the case with box squats performed with additional resistance, however, as the stopping point of the exercise will greatly increase the intensity at the bottom of each repetition, recruiting muscles in a manner that is otherwise difficult with only the exerciser’s own bodyweight and thereby producing a training stimulus difficult to achieve otherwise.
Apart from the usage of additional resistance, the relative height of the box will also greatly affect the difficulty and subsequent results of the exercise, with a box of lower elevation producing better gluteus muscle group recruitment, while boxes of higher elevation will be of lower intensity and thereby easier to perform.
The box squat is performed by exercisers and athletes for the purposes of improving their lower body explosive strength, improving the muscular endurance of the various muscles in the legs, or growing the size of said muscle groups via training stimulus induced muscular hypertrophy.
In the case of powerlifters and similar strength athletes performing the exercise as a part of their sport, the box squat may aid in the mechanics and form of the traditional barbell squat - thereby improving their general performance in competitions by remedying any sticking points they may have in said exercise.
As is clued in by its name, box squats require an exercise box, chair or similar elevated but sturdy implement on which the exerciser may sit on during the bottom of the repetition.
This is all that is required in order to perform the box squat, though if the exerciser is choosing to utilize additional resistance during the exercise, they will also require a suitable weight implement in order to do so.
Generally, a barbell and rack is what exercisers use when performing box squats with the use of additional weight, though it is also possible for the exerciser to grip a pair of dumbbells in both hands, or even a pair of kettlebells, depending on the amount of weight required.
The box squat, being a compound type exercise, is capable of activating a large variety of muscle groups in varying capacities and intensities, with muscle groups being contracted the most and being responsible for the majority of the force involved in the movement being dubbed “primary mover muscles”.
This is adjunct to secondary mover muscles, of which are activated in order to aid the primary mover muscles to a certain extent, and are otherwise activated to a level that is nonetheless significant, though not to the scope that primary mover muscles are.
Finally, there are stabilizer muscles, of which are primarily contracted in an isometric or static capacity and otherwise do not lengthen or shorten like primary or secondary mover muscles, resulting in significantly reduced training stimulus (if any at all).
The primary purpose of stabilizer muscle groups is to ensure the stability of the weight being moved, as well as to ensure the exerciser does not injure themselves by way of stabilizing their trunk and prevention of the primary and secondary mover muscles overextending.
The primary mover muscle groups involved in the box squat are the four heads of the quadriceps femoris, the gluteus muscles that make up the buttocks and the hamstring muscles that run along the posterior of the femur.
These muscle groups are all activated to a significant extent, with the quadriceps femoris being utilized most intensely during the eccentric portion of the repetition wherein the exerciser is lowering themselves to a sitting position atop the box.
Conversely, the hamstrings and gluteus muscle groups are activated most significantly during the other half of the repetition, particularly during the more explosive motion of the exerciser rising from their sitting position.
Activated to a significant extent during the performance of the box squat are the secondary mover muscles, of which are primarily the hip adductors, the various muscle groups of the calves and the erector spinae - all of which are activated throughout both phases of the repetition in order to aid the primary mover muscles in their functions.
The erector spinae in particular also doubles in function as a stabilizer muscle, as it not only adjusts the exerciser’s back in small motions, but also stabilizes the spinal column and torso throughout the entirety of the movement.
Finally, the stabilizer muscles of the box squat are activated throughout the majority of the exercise’s form in order to reduce the exerciser’s risk of injury, as well as to stabilize the weighted implement they are using (if they are).
The most significant of these is the erector spinae, obliques, and various other core stabilizers that ensure the trunk of the body does not cave in, overextend or otherwise move in such a manner that places the exerciser in a precarious position.
This is all the more significant during weighted box squats, where the additional resistance will force the stabilizer muscles to work harder - aiding the primary and secondary mover muscles to an extent and thereby allowing them to contract dynamically in a more intense manner.
The box squat is performed like any other form of the squat, with the exerciser standing upright with their core braced and their back in a neutral position as they lower themselves at the hips and knees.
If the exerciser is choosing to utilize additional resistance in the form of a barbell, it will generally be placed along the back of the shoulders, while dumbbells will be gripped in both hands so as to retain a balanced distribution of load.
It is during the completion of the first phase of the repetition that the box squat differs from the traditional bodyweight or barbell squat, however, as the exerciser will instead rest the entirety of their bodyweight (and any additional weight involved) upon the box, completely arresting the motion and requiring that the exerciser utilize their own strength to rise once more from their position.
Once fully resting on the box, the exerciser will push their legs downward explosively, contracting their gluteus muscles and tightening their core.
If performed correctly, the exerciser will rise back to the original standing position, completing a single repetition of the box squat exercise.
When choosing an appropriate volume of repetitions per set, the exerciser must take into account whether they are utilizing an appropriate level of resistance or not.
Generally, if the exerciser is choosing to perform the box squat with their own bodyweight alone as a source of resistance, a repetition scheme of 12 to 18 repetitions per set should provide enough training stimulus without overly fatiguing the stabilizer muscles involved, or placing the exerciser at risk of connective tissue strain.
However, this is not the case for exercisers performing the box squat with the use of a barbell or set of dumbbells.
In this particular circumstance, the exerciser must identify the appropriate amount of resistance that allows them to maintain proper form while still performing a set of repetitions between 5 and 12, as any higher may place the exerciser at risk of injury, and any lower may require resistance that is potentially dangerous to utilize in a repetitive manner.
Other factors that the exerciser may wish to bring into consideration in the particular angle of their hips in relation to their knees, as the generally agreed “safety” point for most forms of the squat exercise is of the hips being at a parallel point to the knees, with the hips being placed above the knees putting said knees at risk of injury from the added pressure.
In the box squat, this particular mechanic of the exercise is mediated by the elevation of the box, and as such the exerciser must utilize one that is low enough for them to achieve this parallel angle throughout the exercise in order to reduce the risk of injury as well as to improve posterior chain muscle group recruitment.
The box squat, like most variants of the squat, is a highly versatile exercise capable of inducing a wide variety of positive effects in exercisers who perform it on a regular basis, and with proper form.
Apart from the general benefits that may be received by the very nature of the box squat as an exercise, it presents several characteristics that are difficult to produce with the use of other exercises - with some even being superior to that of the traditional barbell squat in certain respects.
The box squat’s nature as a compound movement means that it is capable of activating and thereby improving a wide variety of muscle groups in a simultaneous manner, thereby saving the exerciser time and consequently also training their entire lower body’s strength output in a manner that is difficult to achieve with isolation exercises.
As the box squat has a rather unique form that focuses on an explosive output of force in “the hole” or the bottom of the squat movement, it can therefor train the exerciser in this particular motion, carrying over to other exercises or athletic activities such as the deadlift or squat - or even in deep jumping motions, such as would be the case in high jump athletes.
During the bottom of the traditional barbell squat and similar exercises, the coccyx or tailbone is placed at risk if the exerciser is utilizing improper form or otherwise squatting at a depth that places undue pressure on the tail end of the spinal column.
This is not present in any way during the performance of the box squat, as the presence of the box itself acts as a support mechanism during the bottom of the repetition that entirely removes any sort of pressure or strain that the coccyx and its succeeding spinal discs may undergo.
The box squat may also be used by athletes or exercisers seeking to rehabilitate certain injuries they have sustained, such as in the case of shortened hamstrings or similar injuries that reduce the exerciser’s range of motion during a squat movement.
The reduced range of motion involved in the box squat - combined with the reduced pressure it places on connective tissues by forcing the exerciser to pause in the middle of the repetition - make it an excellent tool that allows exercisers with minor to moderate tissue injuries to still perform a squatting motion in partial repetitions, thereby inducing an anabolic stimulus that can aid in recovery.
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