ATG Split Squat: What it is, Muscles Worked, and Benefits

published by: Debbie Luna
Last Updated:
September 28, 2022

It is a common misconception that riding the knees over the toes is harmful to the knee joint. This false information has been passed down carelessly without any substantive claim. Doing knees over toes exercises like ATG split squats, is not only safe, but also beneficial to strengthening the quads, and gluteal muscles.

The ATG split squat is a variation of the squat with a unilateral application and is performed as deep as a squat can go. It primarily targets the vastus medialis oblique muscle. Furthermore, aside from increasing muscle strength, ATG split squats are beneficial in improving ankle mobility, knee stability, and balance.

What is an ATG Split Squat?

The ATG split squat, which is short for ass to grass split squat or Athletic Truth Group, is a variation of squat exercises that primarily works the VMO muscle (vastus medialis oblique). It was popularized by Knees Over Toes Guy, Ben Patrick, and is the focal point of his knees over toes philosophy.

atg split squat

The most common problem with allowing the knees to slide forward over the toes is that it puts too much strain on the knees, thus increasing the risk of injury. While it is true that when the knees move forward over the toes, more rotational stress (torque) and shearing forces are placed on the knees; these forces are feeble compared to the body’s capabilities.

How to Perform an ATG Split Squat

To perform the ATG split squat, first, the individual must keep in mind that the whole exercise must be done slowly and to try to target perfection in form throughout the activity. The individual should be in a standing position placing one foot in front with a reasonable distance such that the individual can lunge properly and comfortably.

Lunge as low as possible as the front knee goes beyond the toes. The knees must be as far over the toes as possible while still maintaining an upright torso. It is important to avoid excessive lumbar lordosis as the lunge is performed to avoid injury to the spine.

atg split squat muscles

Ideally, the heel on the front leg must be kept on the ground, but this may be hard for people who have limited ankle mobility. It is acceptable to have the front leg’s heel come off the ground, but eventually, it is preferable to keep the foot flat on the ground.

It is important to note that during the eccentric contraction of the exercise, the descent into the squat must be performed slowly on an average of 4-6 before reaching the bottom of the activity. A brief pause is observed before driving through the quads to initiate ascension and get back to the starting position.

Benefits of the ATG Split Squat

Ankle Mobility

Ankle mobility is the range of motion available in all three planes of movement. Poor ankle mobility in any of these three planes may prove to be problematic when performing athletic activities and may be a cause for injury.

Seemingly, ankle mobility has decreased due to the use of footwear that limits the range of ankle motions. With the use of the ATG split squat, the individual has their front heel firmly placed on the ground as the knees go past the toes in flexion, thus stretching the calf muscles and thereby stretching the Achilles tendon.

Although improving ankle mobility is not the main objective as to why ATG split squats are performed, it is an exceptional workout to strengthen the quadriceps femoris, gluteal muscles, and adductors with the added benefit of improving ankle dorsiflexion range of motion.

Knee Pain Reduction

Most individuals are observed to have a favored side when it comes to strength and comfortability in use, may it be the right or left limb. This is most evident in athletes doing their jumps, using one leg more often than the other.

The ATG split squat consists of a unilateral movement that will prevent muscle imbalances caused by placing more weight on one limb than the other when doing back squats or other similar exercises. By being able to balance muscle mass and strength of both limbs, knee pain due to exhaustion and pressure will be decreased.

Tibialis Development 

The ATG split squat can be used as a progression for exercises that target the tibialis muscle, as this exercise also assists in strengthening the tibialis anterior.  In the performance of ATG split squats, when the knees go over the toes, the tibialis muscle is active at that moment. 

Building up the tibialis anterior muscle is very beneficial especially when trying to protect the knees since the tibialis muscle is considered to be one of the muscles that prevents injuries to the knees when developed to a certain point. 

Muscle Lengthening

The ATG split squat’s mechanical movement can be observed to provide a deep stretch to the individual’s hip flexors, especially for the limb placed at the back. Most individuals are observed to have a tight hip, due to a lack of stretch and focusing more on strengthening.

This exercise not only strengthens muscles but is also able to increase the flexibility of the individual. When going into that full squat motion in the exercise the hip flexor or the quadricep muscle will be stretched and as a result over time, will be lengthened.

Muscles Worked by the ATG Split Squat

As mentioned above the ATG split squat primarily works the VMO muscle. However, there may be some tension on the glutes at the top of the exercise. Other muscles such as the back and hip flexors may feel some tension but that is more of a stretch tension than it is due to pressure. 

VMO Muscle

The VMO muscle or vastus medialis oblique muscle acts to extend the lower leg at the individual’s knee joint. It originates from the Intertrochanteric line and mesial lip of the linea aspera of the femur, and inserts into the quadriceps tendon to the base of the patella, and onto the tibial tuberosity via the patellar ligament.

Because of its location, aside from pulling on the tibia to extend the knee, it also contributes to a medial pulling force on the patella. The VMO is engaged as the individual rises from a split squat and corrects the tracking of the patella laterally through the duration of the exercise.


The gluteal muscles’ main action is to extend the thighs at the hip joint. In ATG split squats, the VMO muscle is the primary muscle that works to control the descent and initiate the ascension as the exercise is performed; but towards the end of the ascension, the gluteal muscles are activated to assist in extending the hip joint.

How To Program the ATG Split Squat

ATG split squats, like all other exercises, have specific repetitions, sets, and how fast or slow an exercise is performed to be able to make the activity more efficient and reap better gains from it.

Repetitions and Sets

As the ATG split squat is done in a slow movement, usually about 4-6 seconds during descent, there is no need for high repetitions per set. Typically, it is done with 4-6 repetitions for 5 sets assuring that each movement is controlled and concise. The goal of this exercise is to achieve quality execution rather than a higher quantity of repetitions.

Because ATG squats require to be performed in a slow manner, specifically in the eccentric phase of the exercise, it increases the muscles’ time under tension. By lengthening the duration of the muscle held under tension or strain, it is forced to work harder thus optimizing muscle strength and endurance.


There are multiple ways to progress ATG split squats. The first progression would be to utilize dumbells to create additional resistance. The dumbbells are held in both hands while it hangs beside one’s torso. Prior to performing the exercise, the individual first weigh themselves and computes 25% of their body weight. The computed weight then dictates the weight of the dumbbells to be held.

After the individual finds ease in doing the ATG split squats with dumbbells, the second progression would be with the use of a barbell placed on the individual’s back. This progression proves to be harder as the weight is now placed in a more difficult position, which will require more recruitment of the quads. 

Another progression is to place the weights above the shoulders, but instead of placing them on the back, it is now placed in front, specifically, in a front rack position. This is the most difficult exercise among the three mentioned, as the position of the barbell requires much more strength and stability on the chest to be able to balance the weight throughout the movement.

The challenge of balancing the weight also activates other muscles in the lower extremity to stabilize and keep the center of gravity within the base of support. This progression also makes the VMO muscle activate at a much higher level to be able to move the weight.

Auxiliary Equipment

As mentioned above, when it comes to ankle mobility, most individuals may have a shorter range of motion. The mobility of the ankle will be an obstacle when performing the ATG split squats, but an ankle wedge proves to be a solution for that problem. 

An ankle wedge is placed under the individual’s heel of the foot in front and this is used to elevate the heel and not force as much ankle dorsiflexion to avoid pain or injuries occurring. Not only does the ankle wedge provide such assistance, but it is also capable of forcing more recruitment from the VMO as compared to not using it.

This is because it allows for more forward tracking of the knee without the restraint of insufficient ankle or hip mobility. With the help of an ankle wedge, the knee can be placed in a fully flexed position, thus maximizing the range of contraction that the muscle undergoes.

Final Thoughts

The ATG split squat is a hard exercise to perform, especially for people who have limited ankle or hip mobility. It is arguably one of the most demanding knees over toes exercises, but also one of the finest techniques to increase knee durability since it combines hip flexor stretching with a fully bent knee quadriceps loading.

It may be extremely difficult to perform in the beginning, but continuous training and religious stretching of the calves and hip flexors will significantly improve ankle and hip mobility, thus removing the need for assistance and being on the way to bulletproofing your knees.


1. Fry AC, Chadwick Smith J, & Schilling BK. Effect of knee position on hip and knee torques during the barbell squat. JSCR. 2003; 17(4): 629-633

2. Horschig DA. Can The Knees Go Over The Toes? Squat University. Published January 29, 2016.

Debbie (Deb) started powerlifting and Olympic lifting in High School as part of her track team's programming; She continues to train in order to remain athletic. Inspire US allows Deb to share information related to training, lifting, biomechanics, and more.
Inspire US serves as an informational hub for people looking to start their fitness journey.
The information on this website has not been evaluated by the Food & Drug Administration. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. The information being shared is for educational purposes only. You must consult with a medical professional before acting on any content on this website.
Copyright © Inspire US 2022