Hip internal rotation is the thigh bone turning inward inside its socket, and it is the direction most commonly missing in adults who move perfectly well otherwise. Start with the thing this page has to say before anything else: Limber does not measure it. There is no rotation test in the battery, and none is planned in the build.
The five tests are the toe touch, the knee-to-wall, the shoulder reach, the hip flexor test and the deep squat. The two nearest a hip are the deep squat and the hip flexor test, and neither is a rotation measure. So everything below is about a direction you can train here and cannot score here, and it is better to say that at the top than to imply otherwise for eleven paragraphs.
The short answer
- Internal rotation turns the thigh inward at the hip. It is a real direction with real work behind it.
- No test on this site or in the app reads it. The nearest readings measure other directions.
- It is the direction a hip needs to stand on one leg, change direction, and sit into a squat without the pelvis rolling under.
- You can check it yourself, seated or face down, and compare your two sides. You cannot validate it.
- Total rotation — both directions added together — is more informative than one direction alone.
- Bone shape limits it in some people and no exercise changes bone.
What hip internal rotation is
The hip is a ball in a socket, so the thigh bone can spin about its own long axis as well as swing. Turning the thigh inward, so the kneecap points more toward the midline, is internal rotation. Turning it outward is external rotation.
The confusing part is what the lower leg does. With the hip bent to ninety degrees — sitting on a chair, knee bent — the shin swings outward, away from the midline, when the hip rotates inward. The shin travels the opposite way to the thigh. Almost everyone who checks this at home gets it backwards once.
Why the direction matters is easier to state than to feel. Every step on one leg asks the pelvis to rotate over a planted femur, which is internal rotation at that hip whether you think of it that way or not. Changing direction asks for it quickly. Sitting into a deep squat asks the hips to flex, spread and rotate at once, and when internal rotation runs out early the pelvis rolls under at the bottom instead. Deep squat mobility covers that from the squat's side.
We do not measure it
The honest statement, at full strength, because it is the one this page exists to make.
Limber's battery is five tests and not one of them reads rotation at either hip. The deep squat test scores the whole lower body in four bands from one position and cannot say which joint or which direction was the limit. The hip flexor test reads how far a hanging thigh drops toward extension, per side, in three bands. The app's hips area is built from half of each of those. Average two non-rotation measures and you still have no rotation measure.
There is no rotation score in the app, none on the web, and none in the build. If a page anywhere implies one exists here, it is wrong. The web side carries the check and refuses the number: the seated compare inside the hip mobility test sets your two sides against each other and stops there. What follows is that same check, done at home, and it is worth doing anyway.
Checking it at home
Two positions, both free, neither validated.
Seated. Sit tall on a chair or bench with the knees bent at ninety degrees, feet flat, thighs parallel. Keep the thigh still and swing one shin outward, away from the midline, as far as it goes without the same-side buttock lifting off the seat. Note roughly how far. Repeat on the other side and compare. The lift of the buttock is the cheat, and it is what makes a poor hip look adequate. The hip mobility test carries this seated check beside a squat hold and a hip flexor reading, and it leaves the rotation deliberately unscored — your two sides against each other and nothing else — for the reason above.
Face down. Lie on your front, bend both knees to ninety degrees, and let both shins fall outward under gravity. Keep the front of both hips pressed to the floor. The side whose shin falls further has more internal rotation. This version is easier to judge because gravity does the moving and you only have to stop the pelvis lifting.
Take both readings warm, on the same day, at the same time. What you are looking for is a difference between your own two sides and a change in your own reading over weeks, not a comparison against a published number. Soucie and colleagues, in Haemophilia in 2011, produced normal joint range values by age and sex from 674 people aged 2 to 69 — a good study, and a reminder that the norms circulating for joint range come from samples of that modest size. Grade: moderate. Useful as orientation. Not a threshold to hold yourself against.
Total rotation, not one number
Wilk and colleagues, in the American Journal of Sports Medicine in 2011, followed professional baseball pitchers and found that total rotational motion — internal plus external added together — was more informative than the internal-rotation deficit taken alone. A shoulder that had lost inward range but gained outward range, keeping its total, behaved differently from one whose total had dropped.
Grade: solid in the shoulder, and it is a shoulder. No equivalent study exists for hips, so treat this as a borrowed idea rather than a finding transferred.
Borrow it anyway, because it changes what you do with your home check. Measure both directions on each hip. If one hip has less inward range and correspondingly more outward range, with the total about equal to the other side, that is a distribution — probably from what you do — rather than a loss. If one hip has less of both, the total has dropped, and that is the more interesting reading.
What a clinical test can settle
Not as much as its confident name suggests.
Reiman and colleagues reviewed the clinical tests for hip impingement and labral pathology in the British Journal of Sports Medicine in 2015 and found them sensitive and not specific. In plain terms: a negative result is fairly good at ruling the problem out, and a positive result is poor at ruling it in. Plenty of hips light up on these tests without having the thing the test is named after.
Grade: reasonably solid. The reviews agree with each other and the direction of the error is consistent.
Frank and colleagues found cam-type hip morphology — extra bone at the head-neck junction of the femur, which blocks deep flexion and inward rotation mechanically — in roughly a third of asymptomatic volunteers and over half of asymptomatic athletes, reviewing imaging in Arthroscopy in 2015. Grade: reasonably solid for the prevalence, unsettled for what it means. Which is why Griffin and colleagues' Warwick Agreement, in the British Journal of Sports Medicine in 2016, defines the syndrome as symptoms, clinical signs and imaging together, never imaging alone.
Put the three together and the practical rule is short. A hard block or a pinch at the front of the hip, in the same place every time, is a ceiling to work under rather than a problem to press into. Pain that persists, wakes you at night, radiates into a limb, comes with numbness or weakness, or followed a fall or an injury is a matter for a clinician who can examine you. Nothing here diagnoses anything and nothing here is treatment.
The two moves that train it
The catalogue has 56 moves, ten of them filed to the hips, and two of those work the inward direction directly.
M012 90/90 Hip Switch — dynamic, 45 seconds, on a mat, level 2, cleared for warm-ups. Sitting with one leg bent in front and the other bent out to the side puts the front hip in external rotation and the back hip in internal rotation at the same time, and switching between sides moves both through their range. It is the most efficient rotation position there is, and the 90/90 guide covers the setup errors that make it useless.
M022 Standing Hip CARs — dynamic, 40 seconds per side, no equipment. Standing on one leg, the other knee drives up, sweeps out, turns over and travels behind you, slowly, under your own control. It takes the joint around its whole outline, which is the only way to find out where the outline stops in each direction rather than only in the one you stretch.
Both are dynamic rather than holds, which suits a direction most people have little of. One rep is one breath cycle, six to twelve reps, easing off at any pinch deep in the socket.
Where to start
Do the face-down check on both hips and write down which side falls further. Then put the 90/90 switch in your warm-up and the standing hip circles wherever they fit, four or five days a week, and re-check in three weeks.
Do not expect a number on this site to move because of it, for the reason printed at the top. What you can watch instead is your own home check, whether the deep squat position feels different at the bottom, and whether standing on one leg has stopped feeling like a balance problem. If the word "tight" is what brought you here, tight hips: the causes separates the four different things it can mean, and the rest of the cluster is under hips and legs.
Questions
Does Limber measure hip internal rotation?
No. The battery is the toe touch, knee-to-wall, shoulder reach, hip flexor test and deep squat, and none of those reads rotation at the hip. The two nearest readings measure flexion and extension respectively, and averaging them into a hips score does not produce a rotation measure. There is no rotation test in the app and none in the build.
How do I test hip internal rotation at home?
Lie face down, bend both knees to ninety degrees, and let the shins fall outward while keeping the front of both hips on the floor. The side whose shin falls further has more inward range. The seated version works too, swinging the shin away from the midline without letting the buttock lift, and both are comparisons against your own other side rather than against any published figure.
Why is internal rotation the direction most often missing?
Partly habit: almost nothing people do deliberately trains it, while sitting cross-legged, standing turned out and most stretching routines train the opposite direction. Partly structure: socket orientation and the shape of the femur vary widely, and cam-type bone blocks the inward direction mechanically in a substantial minority of people with no symptoms at all.
Is a lack of internal rotation a problem?
It depends on what else you have. Total rotation, adding both directions together, is the more informative reading — that finding comes from pitchers' shoulders rather than hips, so treat it as a borrowed idea. A hip with less inward range and more outward range, totalling the same as the other side, is a distribution. A hip with less of both has lost range.
Can stretching change hip bone shape?
No. Bone is not a tissue property that responds to holding a position, and a hard block at the front of the hip that arrives in the same place every day is a ceiling rather than a target. What can change is everything on the way to that ceiling, which for most people is more room than they currently use.
Which moves work internal rotation?
Two in this catalogue: the 90/90 hip switch, a 45-second dynamic move that puts one hip in each rotation at once, and standing hip circles, 40 seconds per side, which take the joint slowly around its whole outline. Both are dynamic rather than static holds, which suits a direction most people cannot yet sit comfortably inside.