Squat

In a squat, the hips, knees, and ankles bend together as you lower yourself and extend together as you rise. Because it is a closed-chain exercise, in which your body moves while your feet stay on the floor, it engages the lower-body muscles together rather than using just one joint. The main muscles working are the quadriceps femoris at the front of the thighs, the gluteal muscles in the buttocks, and the trunk muscles that support the body upright.

The name “squat” covers several different forms. They vary with stance width, toe direction, how upright you hold your trunk, where you hold the weight, and how far you lower yourself.

• Stance width and toe direction — These change how much the hips rotate and the path the knees follow. A shoulder-width stance with the toes turned slightly outward is the most common.
• Trunk lean — Keeping the trunk more upright brings the knees farther forward, while leaning the trunk forward shifts the hips back and places more demand on the hips.
• Weight placement — Where the weight sits—in front of the body (front squat), on the upper back (back squat), or in front of the chest (goblet squat)—changes how you maintain your balance.
• Depth — This can range from lowering until the thighs are parallel to the floor to bringing the buttocks down close to the heels.

• Bodyweight exercise squat — The most basic form, using only your bodyweight. It is useful for learning the movement.
• Box squat — Sit down on a chair or box behind you, then stand back up. This lets you practice with a set depth.
• Front and back squats — Only the barbell position changes, but this changes the direction in which the body receives the load, so the movement feels different too.
• Single-leg squat — Because you stand on one leg, balance and control of the base of support become important. The lunge, in which you step one foot forward, belongs to a similar family of movements.

There is no fixed order of difficulty. Single-leg variations demand more balance, and deeper variations involve greater joint movement, but which is better depends on your goals and physical condition.

You have probably heard someone say, “Don't let your knees go past your toes.” This has long been a widely used principle for teaching squats.

Where this advice came from. Keeping the knees back reduces the forces on the knee joint, particularly around the kneecap. It can therefore be an option to consider for people with knee discomfort who want to reduce the load on their knees.

Why the perspective has broadened. If you prevent the knees from moving forward, you have to lean your upper body farther forward and push your hips farther back to stay balanced. This shifts more of the load to the hips and lower back. The current perspective is to view this as a question of how the load is shared among the joints. The knees moving past the toes is not, in itself, a criterion for a problem.

The comfortable position differs from person to person. People with longer shins need their knees to move forward to some extent to maintain balance. The range through which the ankle bends forward (ankle mobility) and the range through which the hips move also vary between individuals. It is also common to see weightlifters squat with their knees moving past their toes.

So rather than judging technique by knee position alone, it is helpful to also check whether the whole sole of each foot stays on the floor, whether the knees point in the same direction as the toes, and whether the trunk can maintain its position comfortably. For knees moving inward, see dynamic knee valgus. Reading about the deadlift alongside this entry can help you understand how the lower back and hips are used.

We all make squat-like movements when getting up from a chair, sitting down on a toilet, or picking something up from the floor. Many people therefore say that practicing squats has made going up and down stairs or getting up from a seat noticeably easier. After exercise, the fronts of the thighs and the buttocks may feel sore and tight, but this often eases naturally within a day or two.

1. Place your feet about shoulder-width apart with your toes turned slightly outward. 2. Breathe in as you push your hips back and bend your knees to lower yourself. Think of sitting down in a chair. 3. Press into the floor through the whole sole of each foot. If your heels lift, reduce the depth a little. 4. Breathe out as you push the floor away with your feet and stand up. 5. Start with 8–12 repetitions at a time using just your bodyweight, then gradually increase the repetitions or weight as you become more comfortable.

• You do not need to keep your lower back perfectly fixed. Gently engage your abdominal muscles so your trunk can hold its position comfortably, and look toward the floor in front of you.
• The right depth is one you can reach without pain or losing your form. Deeper is not necessarily better.
• If your heels keep lifting, try placing them on a thin board or widening your stance a little.

If you feel a sharp pain at the front of the knee during exercise, or the same spot keeps hurting when you go up or down stairs, try reducing the depth, stance width, and repetitions, and start again within a comfortable range. If the pain continues, or your knee swells or feels as though it catches, you can also look into possibilities such as patellofemoral pain syndrome or tendinopathy.