A squat is a strength exercise in which the trainee lowers their hips from a standing position and then stands back up. During the descent of a squat, the hip and knee joints flex while the ankle joint dorsiflexes; conversely the hip and knee joints extend and the ankle joint plantarflexes when standing up.
The squat is one of the three lifts in the strength sport of powerlifting, together with the deadlift and the bench press. It is also considered a staple exercise in many popular recreational exercise programs.
The movement begins from a standing position. Weight is often added; typically in the form of a loaded barbell, but dumbbells and kettlebells may also be used. When a barbell is used, it may be braced across the upper trapezius muscle, which is termed a high bar squat, or held lower across the rear deltoids, termed a low bar squat. The movement is initiated by moving the hips back and bending the knees and hips to lower the torso and accompanying weight, then returning to the upright position.
Squats can be performed to varying depths. The competition standard is for the crease of the hip (top surface of the leg at the hip joint) to fall below the top of the knee; this is colloquially known as "parallel" depth. Although it may be confusing, many other definitions for "parallel" depth abound, none of which represents the standard in organized powerlifting. From shallowest to deepest, these other standards are: bottom of hamstring parallel to the ground; the hip joint itself below the top of the knee, or femur parallel to the floor; and the top of the upper thigh (i.e., top of the quadriceps) below the top of the knee. Squatting below parallel qualifies a squat as deep while squatting above it qualifies as shallow. Some authorities caution against deep squats; though the forces on the ACL and PCL decrease at high flexion, compressive forces on the menisci and articular cartilages in the knee peak at these same high angles. This makes the relative safety of deep versus shallow squats difficult to determine.
As the body descends, the hips and knees undergo flexion, the ankle extends (dorsiflexes) and muscles around the joint contract eccentrically, reaching maximal contraction at the bottom of the movement while slowing and reversing descent. The muscles around the hips provide the power out of the bottom. If the knees slide forward or cave in then tension is taken from the hamstrings, hindering power on the ascent. Returning to vertical contracts the muscles concentrically, and the hips and knees undergo extension while the ankle plantarflexes.
Common errors of squat form include descending too rapidly and flexing the torso too far forward. Rapid descent risks being unable to complete the lift or causing injury. This occurs when the descent causes the squatting muscles to relax and tightness at the bottom is lost as a result. Over-flexing the torso greatly increases the forces exerted on the lower back, risking a spinal disc herniation. Another error is when the knee is not aligned with the direction of the toes, entering a valgus position, which can adversely stress the knee joint. Another error is the raising of heels off the floor, which reduces the contribution of the gluteus muscles.
Kirk Karwoski completing a heavy squat in competition. Note the spotters either side of him and the power cage which the barbell was lifted out of.
Various types of equipment can be used to perform squats.
A power cage can be used to reduce risk of injury and eliminate the need for a spotting partner. By putting the bar on a track, the Smith machine reduces the role of hip movement in the squat and in this sense resembles a leg press. The monolift rack allows an athlete to perform a squat without having to take a couple of steps back with weight on as opposed to conventional racks. Not many powerlifting federations allow monolift in competitions (WPO, GPC, IPO).
Other equipment used can include a weight lifting belt to support the torso and boards to wedge beneath the ankles to improve stability and allow a deeper squat (weightlifting shoes also have wooden wedges built into the sole to achieve the same effect). Wrist straps are another piece of recommended equipment; they support the wrist and help to keep it in a straightened position. They should be wrapped around the wrist, above and below the joint, thus limiting movement of the joint. Heel wedges and related equipment are discouraged by some as they are thought to worsen form over the long term. The barbell can also be cushioned with a special padded sleeve.
Chains and thick elastic bands can be attached to either end of the barbell in order to vary resistance at different phases of the movement. This may be done to increase resistance in the stronger upper phase of the movement in order to better meet a person's 1RM for that phase. Bands can also be used to reduce resistance in the lower weaker phase by being hung from a power rack and the barbell being increasingly supported by them as it is lowered. This can help someone to overcome a 'sticking' point. A squat performed using these techniques is called a variable resistance squat.
Starting position of a front squat using a cross-armed grip
The hack squat as pictured page 70 of George Hackenschmidt's book The Way to Live (1908)
Machine hack squat
A photo of an Indian wrestler performing baithaks (Hindu squats).
A sissy squat machine
The squat has a number of variants, some of which can be combined:
Back squat – the bar is held on the back of the body upon the upper trapezius muscle, near to the base of the neck. Alternatively, it may be held lower across the upper back and rear deltoids. In powerlifting the barbell is often held in a lower position in order to create a lever advantage, while in weightlifting it is often held in a higher position which produces a posture closer to that of the clean and jerk. These variations are called low bar (or powerlifting squat) and high bar (or Olympic squat), respectively.
Sumo squat – A variation of the back squat where the feet are placed slightly wider than shoulder width apart and the feet pointed outwards.
Box squat – at the bottom of the motion the squatter will sit down on a bench or other type of support then rise again. The box squat is commonly utilized by powerlifters to train the squat.
Front squat – the barbell is held in front of the body across the clavicles and deltoids in either a clean grip, as is used in weightlifting, or with the arms crossed and hands placed on top of the barbell. In addition to the muscles used in the back squat, the front squat also uses muscles of the upper back such as the trapezius to support the bar.
Hack squat – the barbell is held in the hands just behind the legs; this exercise was first known as Hacke (heel) in Germany. According to European strength sports expert and Germanist Emmanuel Legeard this name was derived from the original form of the exercise where the heels were joined. The hack squat was thus a squat performed the way Prussian soldiers used to click their heels ("Hacken zusammen"). The hack squat was popularized in the English-speaking countries by early 1900s wrestler, George Hackenschmidt. It is also called a rear deadlift. It is different from the hack squat performed with the use of a squat machine.
Overhead squat – the barbell is held overhead in a wide-arm snatch grip; however, it is also possible to use a closer grip if balance allows.
Zercher squat – the barbell is held in the crooks of the arms, on the inside of the elbow. One method of performing this is to deadlift the barbell, hold it against the thighs, squat into the lower portion of the squat, and then hold the bar on the thighs as you position the crook of your arm under the bar and then stand up. This sequence is reversed once the desired number of repetitions has been performed. Named after Ed Zercher, a 1930s strongman.
Deep knee bend on toes - it is similar to a normal back squat only the lifter is positioned on their forefeet and toes, with their heels raised, throughout the repetition. Usually, the weight used is not more than moderate in comparison to a flat footed, heavy back squat.
Loaded squat jump - the barbell is positioned similarly to a back squat. The exerciser squats down, before moving upwards into a jump, and then landing in approximately the same position. The loaded squat jump is a form of loaded plyometric exercise used to increase explosive power. Variations of this exercise may involve the use of a trap bar or dumbbells.
Variable resistance squat - In keeping with variable resistance training in general, a variable resistance squat involves altering the resistance during the movement in order that it better matches, in percentage terms, the respective 1RM for each strength phase[a] the person is moving through i.e. more resistance in the higher stronger phase and less in the weaker lower phase e.g. 60 kg in the lower phase and 90 kg in the higher phase. Such an alteration of resistance can be achieved by the use of heavy chains which are attached to either end of the barbell. The chains are gradually lifted from the floor as the barbell is raised and vice versa when it is lowered. Thick elastic bands which are more stretched in the higher phase and less stretched in the lower phase can also be used. Combining heavier partial reps with lighter full reps can also help to train the stronger and weaker phases of the movement so the percentage of 1RM lifted for each phase respectively is more similar. Training with variable resistance squats is a technique used to increase speed and explosive power.
Partial rep - Partial rep squats only move through a partial range of movement (PROM) when compared with full squats which move through a full range of movement (FROM). PROM for a squat usually means the higher stronger phase of a squat’s strength phase sequence[a] (strength curve), but may also refer to just squatting for the lower weaker phase. When partial squats are used to strengthen the higher ROM this usually involves significantly increasing the weight in comparison to the weight used for a full squat. The percentage lifted of the stronger higher phase’s 1RM can therefore be increased and not limited by the requirement to move through the weaker lower range of movement e.g. a person lifts 100% of his 1RM for the higher stronger phase which is 150kg. If he did a full squat he would only have been able to do about 66% of his stronger phases 1RM because his 1RM for a full squat, including the weaker lower phase, is 100 kg. Training with heavier partial squats can help to improve general strength and power. It can also be more beneficial for sports and athletics as that ROM is more likely to be required in those activities i.e. it is rare to need to perform a full squat in sport, whereas partial squatting happens frequently. Partial squatting with a heavier weight than a full squat allows for can also help to improve a person’s 1RM for a full squat. When partial squatting only the lower phase this is usually to strengthen that relatively weak phase of the lift in order to overcome a sticking point i.e. a point a person gets ‘stuck’ at and finds it difficult to progress past. It is commonly recommended that partial squats are best used in conjunction with full squats.
Split squat – an assisted one-legged squat where the non-lifting leg is rested on the ground a few steps behind the lifter, as if it were a static lunge.
Bulgarian split squat – performed similarly to a split squat, but the foot of the non-lifting leg is rested on a platform behind the lifter.
Belt squat – is an exercise performed the same as other squat variations except the weight is attached to a hip belt i.e. a dip belt
Goblet squat – a squat performed while holding a kettlebell next to one's chest and abdomen with both hands.
Trap bar squat – a trap bar is held in the hands while squats are performed. More commonly referred to as "trap bar deadlifts."
Monolift squat – a squat using a monolift rack.
Anderson Squat (aka Pin Squat, Bottoms Up Squat) – starting the squat from the bottom position.
Bodyweight or air squat – done with no weight or barbell, often at higher repetitions than other variants.
Overhead squat – a non-weight bearing variation of the squat exercise, with the hands facing each other overhead, biceps aligned with the ears, and feet hip-width apart. This exercise is a predictor of total-body flexibility, mobility, and possible lower body dysfunction.
Hindu squat – also called a baithak, or a deep knee bend on toes. It is performed without additional weight, and body weight placed on the forefeet and toes with the heels raised throughout; during the movement the knees track far past the toes. The baithak was a staple exercise of ancient Indian wrestlers. It was also used by Bruce Lee in his training regime. It may also be performed with the hands resting on an upturned club or the back of a chair.
Jump squat – a plyometrics exercise where the squatter engages in a rapid eccentric contraction and jumps forcefully off the floor at the top of the range of motion.
Pistol squat – a bodyweight single leg squat done to full depth, while the other leg is extended off the floor and positioned somewhere in front. Sometimes dumbbells, kettlebells or medicine balls are added for resistance. Pistol squats may be performed with the foot flat on the floor or with the heel raised.
Shrimp squat – also called the flamingo squat, a version of the pistols squat where instead of extending the non-working leg out in front, it is bent and placed behind the working leg while squatting, perhaps held behind in a hand. Shrimp squats may be performed with the foot flat on the floor or with the heel raised.
Jockey squat - a half-squat, performed by being balanced on the forefeet throughout the repetition, with fingertips touching across the chest. This squat can be performed quickly and in high repetitions.
Sissy squat – the knees travel over the toes, stretching the quadriceps and the body leans backwards. Can be done in a special sissy squat machine, and can also be weighted.
Sumo Squat - also known as Plie Squat, in this variation legs are wider than shoulder width.
Although the squat has long been a basic element of weight training, it has not been without controversy over its safety.
Some trainers claim that squats are associated with injuries to the lumbar spine and knees. Others, however, continue to advocate the squat as one of the best exercises for building muscle and strength. Some coaches maintain that incomplete squats (those terminating above parallel) are both less effective and more likely to cause injury than a full squat (terminating with hips at or below knee level).
A 2013 review concluded that deep squats performed with proper technique do not lead to increased rates of degenerative knee injuries and are an effective exercise. The same review also concluded that shallower squats may lead to degeneration in the lumbar spine and knees in the long-term.
Squats used in physical therapy
Squats can be used for some rehabilitative activities because they hone stability without excessive compression on the tibiofemoral joint and anterior cruciate ligament.
Deeper squats are associated with higher compressive loads on patellofemoral joint and it is possible that people who suffer from pain in this joint cannot squat at increased depths. For some knee rehabilitation activities, patients might feel more comfortable with knee flexion between 0 and 50 degrees because it places less force compared to deeper depths. Another study shows that decline squats at angles higher than 16 degrees may not be beneficial for the knee and fails to decrease calf tension. Other studies have indicated that the best squat to hone quadriceps, without inflaming the patellofemoral joint, occurs between 0 and 50 degrees.
Combining single-limb squats and decline angles have been used to rehabilitate knee extensors. Conducting squats at a declined angle allows the knee to flex despite possible pain or lack of mobilization in the ankle. If therapists are looking to focus on the knee during squats, one study shows that doing single-limb squats at a 16-degree decline angle has the greatest activation of the knee extensors without placing excessive pressure on the ankles. This same study also found that a 24-degree decline angle can be used to strengthen ankles and knee extensors.
Different Sets For Squats
Forced repetitions are used when training until failure. They are completed by completing an additional 2-4 reps (assisted) at the end of the set. Partial repetitions are also used in order to maintain a constant period of tension in order to promote hypertrophy. Lastly, drop-sets are an intense workout done in at the end of a set which runs until failure and continues with a lower weight without rest.
The world record for the biggest equipped squat, with a multi-ply squat suit and knee wraps, is 595 kg (1,312 lb) performed by Nathan Baptist on February 6th 2021 in Utah, United States.
The raw world record with knee wraps is 525 kg (1,157 lb) performed by Vlad Alhazov on 23 December 2018.
The raw world record without knee wraps belongs to Ray Williams who lifted 490 kg (1,080 lb) in March 2019, at the Arnold Classic in Columbus, Ohio.
The women world record with a multi-ply suit is held by American Becca Swanson with a recorded competition lifted 387 kg (854 lb).
The women world record raw without knee-wraps is held by April Mathis with a 279 kg (615 lb) on October 29, 2011 at Southern States in Florida.
The most squats with 130 kg in two minutes was Dutch woman Maria Strik. She squatted a weight of 130 kg, 29 times within two minutes.
The most bodyweight squats performed in one hour is 4,708 by Paddy Doyle (UK) in November 2007.
The most bodyweight sumo squats in one hour is 5,135, and was achieved by Dr. Thienna Ho (Vietnam) in December 2007.
The most pistol squats in one minute (male) is 52, and was achieved by William Rauhaus (Germany) in Bad Aibling, Germany, on 27 July 2016.
Silvio Sabba from Italy has:
the most squats in one minute carrying a 60 lb pack: 47 in June 2016 (the previous was 44 by Paddy Doyle)
the most squats in one minute carrying an 80 lb pack: 42 in July 2016
the most pistol squats on a scaffold pole in one minute: 30 in October 2013
the most pistol squats on an American football in one minute: 23 in July 2015
^ abA movement may be considered as having any number of strength phases but usually is considered as having two main phases: a stronger and a weaker. When the movement becomes stronger during the exercise, this is called an ascending strength curve i.e. bench press, squat, deadlift. And when it becomes weaker this is called a descending strength curve i.e. chin ups, upright row, standing lateral raise. Some exercises involve a different pattern of strong-weak-strong. This is called a bell shaped strength curve i.e. bicep curls where there can be a sticking point roughly midway.
^ abcJaberzadeh S, Yeo D, Zoghi M (September 2016). "The Effect of Altering Knee Position and Squat Depth on VMO : VL EMG Ratio During Squat Exercises". Physiotherapy Research International. 21 (3): 164–173. doi:10.1002/pri.1631. PMID25962352.