Ever hear a trainer try to explain why their client can't get below parallel on a squat? Once you get past the token explanations about bad knees, aching backs, or tight body parts, the next issue is usually the hips.

It's no secret that to have a great squat, you have to have great hip mobility. Unfortunately, saying that you need hip mobility to squat deep is like saying you need a lot of money to be rich; merely acknowledging that you need it doesn't make it so. As any personal-finance guru will tell you, if you're going to get rich, you'd better have a plan.

The hips have many different functions. They must be both stable and mobile at different times and in different planes, along with being able to abduct, adduct, extend, and rotate on demand. But when we discuss hip mobility in the context of the squat, what we're really talking about is hip flexion.

Hip flexion is the technical term for a decrease in joint angle between the femur and pelvis. This occurs from either side of the joint, by raising the leg towards the abdomen – like when you run – or by lowering the upper body toward the leg – like when you squat down.

If you want to have any chance of squatting below parallel with a weight on your back, then you're going to need at least 110-125 degrees of hip flexion. Achieving full squat depth with anything less than full range of motion at the hip requires your body to make a number of biomechanical compromises.

Following the joint-by-joint approach, when the hip lacks flexion, the joints above it (the lumbar spine), and below it (the knee) will overcompensate to make up the difference.

It's something of a Ponzi scheme our bodies have developed, robbing stability from one joint to provide mobility for another. But while this type of compensated movement may allow you to achieve certain positions, it puts excessive strain on the back and knees.

When your body isn't ready for these positions, the repetitive stress eventually leads to structural overload, inflammation, and a long-term relationship with your orthopedic surgeon. Show me a guy who says that squats hurt his knees or tweak his back and I'll show you a guy with a hip mobility problem.

Typically when we see lifters struggling to reach full depth during a squat we immediately think of the posterior chain – tight hamstrings, glutes, lower back, etc. Yet limitations in hip flexion can come from the front or the back, depending on what's being restricted. Hip restrictions come in three main flavors – muscular, capsular, and structural (bone) – each requiring different solutions.

Hip Structure

Structural restrictions occur when the femoral head and neck don't "fit" properly into the acetabulum (the cup-shaped cavity at the base of the pelvis). Because this is often a genetic trait, sometimes you can't do anything about it other than curse your parents for passing you their lackluster DNA.

However, these can also form as the result of increased exposure to activities that promote anterior pelvic tilt, like hockey and distance running. The forward tilting of the pelvis is usually the result of a shortening and tightening of the hip flexors and lumbar erectors, coupled with a lengthening and weakening of the glutes and abdominals. Vladimir Janda labeled this "lower cross-syndrome."

This type of alignment sets the bottom of the pelvis on a crash course with the top of the femur every time you flex your hip. According to Janda, to fix this faulty posture, the tight hip flexors must first be inhibited through stretching and massage followed by strengthening exercises for the glutes and lower abdominals.

Exercises and articles on glute and abdominal strengthening are a plenty and don't require much repeating – basically, don't skimp on your planks, leg raises, bridges, and deadlifts.

Here are two drills to help melt away the layer of ice that's likely formed around the front of your hip over the last decade:

Hip Flexor Stretch (Wall or Bench)

This is one of the most effective and universally-despised stretches ever. Perhaps this is because most lifters' hip flexors are shorter than Gary Coleman ducking under a subway turnstile, or maybe they just don't put enough effort into their stretches. Either way, grab a bench or a wall, pour yourself a glass of Scotch, and settle into position for 2-3 minutes a side.

Psoas Active Release with Plate

Psoas stretches might be a dime-a-dozen, but soft-tissue techniques are almost nonexistent. Because the psoas sits so deep within the body, it can be very difficult to access through touch. Here's an easy way to get pressure onto this stubborn muscle using a common weight plate and some elbow grease.

Make sure to place the weight plate slightly off center, between the ribs and the pelvis. I like to center the pressure about two-inches from the belly button laterally, and about one-inch down. Once you feel weight pressing on the psoas, move your leg through hip flexion activation to breakup any scar tissue or fascial tightness.

Perhaps the least talked about or understood cause of limited mobility is tightness in the joint capsule itself. Like all synovial joints, the hip is encased in a flexible membrane – like a piece of fruit suspended in a bowl of Jell-O – that provides the hip with an additional layer of flexible support.

This membrane is referred to as your joint capsule. Although it might not receive much attention, it's one of the most important pieces in the mobility puzzle. When the capsule becomes stiff and tight, it compresses the articulating surfaces of the joint and alters what's called accessory joint movement.

Accessory movements at the capsular level are necessary for larger physiological movements like flexion or abduction to occur normally. For example, to avoid impinging the anterior capsule and psoas tendon during hip flexion, a slight posterior glide of the femur must occur. Without it, the joint must compress against these structures to achieve its goal of moving.

That brings us to the wonderful world of joint mobilization! This phrase gets thrown around a lot in the strength and conditioning world as a stand-in for any exercise that purports to improve range of motion.

However, joint mobilizations are actually very specific techniques that involve applying angled pressure to a joint to manually create accessory movement, stretch the joint capsule, and decompress the surrounding tissue.

Traditionally performed by a manual therapist with the assistance of a traction belt, many joint mobilizations can be recreated by yourself with a little bit of know-how and a two-inch stretch band.

BottomUp Hamstring Stretch with Band

Loop a stretch band around a squat cage. Place your leg through the middle of the band, pulling it to where your hip and leg meet. Walk away from the cage, causing the band to stretch.

Once you have a good amount of tension, place the band-leg forward and the free leg back. Bring your hands to the ground, bending both knees. Then, keeping your hands in a fixed position, begin to straighten the knees as much as possible, pushing the hips back toward the cage. Repeat for 15-20 cycles.

Top-Down Forward Bend with Band

Starting from the same setup as the bottom-up mobilization, this time keep both legs straight and reach forward to touch the toes of the forward foot. Press your hips back toward the cage as you lean forward. Repeat for 15-20 cycles.

Squat with Band

Here the band is in the same position around the upper leg, but the anchor is lower to the ground (about 6-8 inches from the floor) so the tension is directed back and down. Walk away from the cage to increase band tension at the hip and perform 10-15 deep squats for each leg.

Last but not least are muscular restrictions. These are the big men on campus in the strength and conditioning world, receiving much of the attention from both trainers and clients.

These fall into three categories. First are soft-tissue entrapment issues, where tissue becomes gnarled or stuck together, like in the case of trigger points and myofascial adhesions. Second are problems with excessive stiffness or resistance to changes in length. Finally, problems involving muscle length, where a muscle has actually lost sarcomeres and therefore has become shorter.

Restrictions in the hamstrings, glutes, or lower back can all limit hip flexion. I find that a lacrosse ball works best to free-up entrapment issues, while a stretch band works best on length and stiffness problems.

High Hamstring Mash

The proximal hamstring attachments on the backside of the pelvis exist in an area of high stress and tension in the body, making them prone to stiffness and adhesions. Compound that with the eight or more hours most people spend sitting directly on this area each day – squishing it like an overstuffed flatbread Panini – and you have plenty of room for problems to occur.

To free up this area, place a lacrosse ball directly under the glute fold (slightly closer to inside) and then sit on something hard (insert your own jokes here) like a plyo block or the floor. Roll back and forth over the hamstring attachment, ungluing the ugly mess of matted down tissue that has likely formed there.

Hamstring Drive-Down

Loop a 1-inch stretch band about a quarter of the way up one of the columns on a squat cage. Lie down in front of the cage, with your head directly under the band and put one foot through the looped band. Keeping your leg straight, push the band down to the floor and then slowly control the movement back to the top. The heavy eccentric load forces a controlled lengthening of the posterior hip and hamstring, thereby increasing flexibility and decreasing stiffness.

Summing up, limitations at the bottom range of your squat can be coming from the backside of the pelvis through stiffness or adhesion, or the front side through capsular restriction and decreased accessory motion. Identifying the source of the restriction will have an obvious effect on correcting the limitations in range, as will taking the course of action described in this article.

Adam Vogel is the founder of Pure Performance Training, where he combines science and individualization to help people look better, improve athleticism, and eliminate chronic pain. Adam has coached professional athletes from the New England Patriots, Atlanta Thrashers, and New England Revolution.

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