A thread on Box Squats & their use for improving pelvic mechanics, a squat pattern, & force output

Box squats are often used as a means to improve squat strength.

In addition to that, a deeper look into the biomechanics can help us appreciate contextual application of them...
The first thing to consider is that box squats usually stop at ~90 degrees of hip flexion, which is associated with high degrees of internal rotation of the hips.

At this point, the sacrum bone tips forward and the pelvic bones rotate inward for femurs (leg bones) to pick up
room to move back into internal rotation.

This is necessary for producing force through the sticking point of a squat.

When someone is lacking proper internal rotation of the hips, you’ll often see them push their hips forward and arch their low back.

This anterior orientation
allows the femurs to pick up internal rotation, but if taken too far, can put increased stress on the low back.

Also, trainees who are missing IR of the hips often “fall through” or drop without control into the bottom of a squat as they create a strategy to bypass IR.
So if I had someone who lacks IR (more on that later), or struggles to produce force through the sticking point of a squat, the box squat is an appropriate choice.
There are a few ways to use box squats:

1. Anterior load - This can help the individual maintain an more neutral spine and helps prevent them from overly arching their low back
2. Posterior load - Better for higher-output squats and more specific carryover to a back squat
3. Adding a ball between the knees - This is better for more of a “prep” drill, but adding a ball that keeps the knees in-line with the toes can allow for the individual to bias pelvic IR if they struggle to access it.
As a bonus activity, you can also use a box for a tool to teach a power output via a vertical jump from a 90 degree box.

Because there is no counter-movement involved here, this would be an initial beginner progression to teach someone to produce force rapidly through hip IR.
How do you know if someone is missing hip IR? A few ways:

1.) A femoral IR test (pictured below)

2.) An active straight leg raise assessment can also be used as a hip and femoral IR test. I go into deep detail on there here:
You can also read more about the importance of hip internal rotation as it relates to athletics, the weightroom, and human movement here:

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More from @Conor_Harris_

8 Feb
A thread on ankle mobility, pronation, common misconceptions, & how to improve it

If you want to:
- Run fast
- Squat/deadlift a lot of weight
- Have good ankle mobility

You want your foot to properly pronate.

Pronation is the transition from force absorption to production...
The biggest misconception I see is that people think pronation is the collapsing inward of the foot as a whole.

That is not the case, and a collapsed foot is indicative of a foot that is likely compensating into pronation, rather than achieving true pronation.
True pronation of the foot involves relative:

- Tibial internal rotation (IR)
- Rearfoot eversion (turning in)
- Forefoot inversion (turning out)

Pronation occurs most in mid-stance in gait, where it is coupled with relative IR of the hips, femur, and tibia.
Read 12 tweets
21 Dec 20
A thread on the biomechanics of hip extension & how to train it

If you want to:
- Stand upright
- Sprint
- Train your glutes & hamstrings properly

You want to have hip extension. Problem is, majority of people & athletes don’t fully have it.

The reason why it’s often.. Image
missing is for a few common reasons:

- Sitting too much: Sitting is hip flexion and the body will adapt to the demands placed on it

- Not training through a full range of motion. Ending your squats and deadlifts with your butt out means you’re not in full hip extension Image
You’ll commonly see people who don’t have full hip extension stand in an Anterior Pelvic Tilt.

I think we know this tightens the hip flexors and back extensors, but it also tightens & restricts ligaments of the hips like the iliofemoral ligament.

This creates a hip flexion Image
Read 11 tweets
6 Nov 20
A thread on knee injuries in females and strategies to help minimize their potential

Weakness of the hip abductor & external rotator (ER) muscles is surprisingly common in otherwise normal & healthy females (Malinzak et al, 2001; Robinson, 2007).

That is just one piece of the..
overall puzzle.

Females tend to have a higher Q-Angle due to wider hips. The research is murky whether or not higher Q-Angle leads to more injuries, but honestly I’m not concerned about that as much as the biomechanical relevance of a higher angle.
When hips are wider, the sacrum is in a relatively higher amount of counter-nutation and the pelvic bones follow it into:

- External rotation
- Abduction
- Flexion
Read 10 tweets
16 Oct 20
A thread on how to improve hip internal rotation

If you want to:
- Be agile
- Be fast
- Get through the sticking point of a squat
- Deadlift

You want to have adequate hip internal rotation (IR).

However, in my experience it is often missing to some degree in many people.
The hip musculature responsible for hip IR are primarily:

- Adductors
- Inner Hamstrings
- Anterior fibers of the Gluteus Medius
- Tensor Fasciae Latae
In human movement, IR is necessary for mid-stance when we have our bodyweight on one leg and we need to propel it to the next leg. In cutting, we obviously need hip internal rotation to drive out of it effectively in a propulsive manner.
Read 13 tweets
9 Oct 20
A thread on the biomechanics of a lateral lunge - and why it’s an amazing position for those with tight glutes & piriformis.

This position is know for training the frontal plane, but it’s so much more than that.

Depending on how you do it, you can improve movement mechanics..
through an understanding of the constraints you can use with the exercise.

The lateral “lunge” is honestly a hinge, and that distinction matters when appreciating the context of when we should choose it in a program.

When we hinge, the pelvic inlet (top) comes closer together
while the pelvic outlet (bottom) spreads apart.

Notice where the posterior hip musculature (glutes & that all-so- known piriformis) attach.

When we hinge, we are essentially “spreading apart” that musculature while the pelvis goes into:

-Internal Rotation
Read 8 tweets
23 Sep 20
A thread on how to train the Glute Max

You often hear terms like “gluteal amnesia” or “my glutes are asleep”

Nah, your positioning and exercise selection probably sucks.

Let’s dig in on how to attack the glutes.

We first should appreciate it’s mechanics to best...
train it.

It has a significant role in:
- External Rotation at the hip and femur (leg bone)
- Hip & Trunk extension
- Hip abduction
- Posterior pelvic tilt

And yet, it is hardly active at all during standing and walking (Neumann, 2010). Interesting, huh?
In order for a muscle to be properly contracted, it needs to be stretched. That is what cues contraction of muscles in the human body.

That’s partially why it doesn’t function much in walking and standing, while it does much more in running.
Read 13 tweets

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