Hip flexor test
A Thomas-style test you can take on the edge of a bed: hug one knee in, let the other leg hang, and read where the hanging thigh settles against the bench line. Both sides, three bands, one 0–100 score.
How to take the reading
- Lie back on a bed or bench with your hips right at the edge.
- Hug one knee to your chest and let the other leg hang. Watch the hanging thigh. Stop at a stretch, never at sharp pain.
- Keep your lower back flat. Note where the hanging thigh rests.
- Swap legs and read the other side.
The bench line is the reference: the flat surface you are lying on, carried forward past the edge. Above it, level with it, below it — that is the whole reading.
The lower back is what makes this test lie. Let it arch off the bench and the pelvis tips, the hanging thigh drops, and the reading improves without anything about you having changed. Press the small of your back down before you look. If you cannot keep it flat, that is worth knowing too, and the honest reading is the one you took with a flat back rather than the better one you took without.
You are judging your own thigh from an awkward angle, so use a mirror to the side if you have one, or ask someone to look. Whatever you use, use the same thing every time — the comparison is between your readings, and a method change looks exactly like a range change.
What each band scores
| Band | Where the hanging thigh rests | Score |
|---|---|---|
| 1 | Thigh lifts above the bench line | 25 |
| 2 | Thigh rests level with the bench | 60 |
| 3 | Thigh hangs below the bench | 90 |
Three bands is the coarsest scale in the battery, and the spacing shows why the app does not interpolate band tests: the jump from 25 to 60 is thirty-five points of score for one visible change of position. There is no honest reading between them, so the app does not offer one.
What the hanging thigh measures
How much hip extension you have on that side with the other hip pinned — mostly the iliopsoas and the rectus femoris, plus whatever the front of the hip capsule contributes. The clinical version adds knee angle and thigh position to separate those structures. This one does not, so it reads the front of the hip as a whole.
A short reading is not the same as a tight muscle, and it is worth being blunt about that, because the phrase "tight hip flexors" carries more weight in fitness writing than the evidence behind it supports. Sitting all day changes what the hip is used to, not what it is made of. Hip anatomy varies: Frank and colleagues reported in Arthroscopy in 2015 that cam morphology shows up in around a third of people with no symptoms at all, and bone shape is not something a stretch changes.
Sides differ, and a gap of 12 points or more is what Limber calls an imbalance — one extra move for the side that reads lower, until the gap falls under six.
0 of 5 tests taken. Every link here carries what you have already measured, so the readings travel with you from one instrument to the next.
Nothing on this site is stored and nothing is sent. Your readings live in the address bar and nowhere else, so a link is a survey and closing the tab loses it. Copy the address if you want to keep it, or take the same tests in Limber, where a reading is kept on the phone and measured against the one before it.
Stop at a stretch, never at sharp pain. A stretch across the front of the hip or the top of the thigh is the test working. A pinch deep in the front of the hip joint, or pain in the lower back as the leg hangs, is not — come out of it and take the reading another way, or leave it unread.
See a clinician rather than a web page if pain radiates down the leg, if you have numbness, pins and needles or weakness, if the hip catches or gives way, or if back pain came with fever, unexplained weight loss or any change in bladder or bowel control. This test does not diagnose anything and Limber does not treat anything.
What does a failed hip flexor test mean?
There is no pass or fail on this scale. A thigh that lifts above the bench line reads 25, level reads 60 and hanging below reads 90 — three positions, three readings. A low band says the front of that hip did not let the leg travel far on the day you measured it. It does not say a muscle is damaged, and it is not a diagnosis of anything.
Why does my lower back arch during the test?
Because the pelvis tips forward when the hip runs out of extension, and letting it happen makes the reading look better than it is. Hug the other knee firmly to your chest, press the small of your back into the bench, and read the thigh from there. If you cannot keep the back flat, that is worth knowing on its own — and the honest reading is the one you took with a flat back, not the better one you took without.
Do tight hip flexors come from sitting?
Sitting changes what the hip is used to rather than what it is made of, and the phrase carries more weight in fitness writing than the evidence behind it supports. Hip anatomy also varies from person to person: Frank and colleagues reported in Arthroscopy in 2015 that cam morphology appears in around a third of people with no symptoms at all, and bone shape is not something a stretch changes.
Why only three bands?
Because you are judging your own thigh against a bench edge while lying on your back. Three positions are what that view can honestly separate, and finer bands would be finer than the reading. It is the coarsest instrument in Limber's battery and the app does not dress it up as anything more precise.
Can I take this test without a bench?
You need a firm surface with an edge you can hang a leg off — a bed with a solid edge, a bench, a sturdy table. A sofa is usually too soft to give a stable reference line. Whatever you use, use the same one every time, because the reference line is the measurement.
What does this reading feed?
All of the hip flexor area and half of the hips area in Limber, which together make it three quarters of the Hips group once the deep squat is read as well. The Hips group is one of the five the Range Score averages.
The composite. Whatever you have measured, rolled into one 0–100 reading and drawn as an elevation profile — with the ground you skipped left dashed.
Deep Squat TestThe whole lower body as one screen — depth, heels and whether the bottom of the squat is somewhere you can rest.
Knee to Wall TestAnkle dorsiflexion in centimetres, left and right kept apart. One of two tests in the battery that produce a real measured number.
- Frank JM, Harris JD, Erickson BJ, Slikker W 3rd, Bush-Joseph CA, Salata MJ et al. Prevalence of Femoroacetabular Impingement Imaging Findings in Asymptomatic Volunteers: A Systematic Review. Arthroscopy 2015;31(6):1199–204. doi:10.1016/j.arthro.2014.11.042
- Vigotsky AD, Lehman GJ, Beardsley C, Contreras B, Chung B, Feser EH. The modified Thomas test is not a valid measure of hip extension unless pelvic tilt is controlled. PeerJ 2016;4:e2325. doi:10.7717/peerj.2325
Each address was followed to the record it names before it was written down. Where a paper could not be resolved that way, the page names it in the prose and leaves it unlinked rather than guessing at an address.
One reading is a point. Two are a line.
This page scores one test. Limber runs five — toe touch, knee-to-wall, shoulder reach, hip flexor and deep squat — rolls them into a single 0–100 Range Score, cuts that first score as your datum, and measures every later reading from it. The two wall tests are read in centimetres, the per-side tests keep left and right apart, and areas you never tested stay drawn as untested rather than filled in with a guess.
It works offline and needs no account: your readings stay on the phone.
Limber is in build. There is no store listing yet, so there is no download button here — when there is one it will be a link, not a promise.