Hips
Hip flexor stretches, and the tuck that makes them work
Most people do this stretch by pushing the hips forward, and feel it in the lower back instead of the hip. One change fixes it.
Clinically reviewed by Lee Albert, NMT · 8 August 2026
The hip flexors are a group, not a muscle
Three different things get called the hip flexor. The psoas runs from the lower spine, through the pelvis, to the inside of the thigh, so it crosses the lower back as well as the hip. The iliacus lines the inside of the pelvis and joins it. The rectus femoris is the one quadriceps muscle that crosses the hip as well as the knee, which is why a stretch that leaves the back knee straight misses it entirely.
That matters because the three want slightly different positions. A half-kneeling lunge with the back knee bent and the pelvis tucked reaches all three. The same lunge with a straight back leg and an arched back reaches almost none of them, which is the version most people have been shown.
Why it usually gets felt in the lower back
The standard instruction is to push the hips forward. The problem is that the hip only extends so far, and once it runs out, the pelvis tips forward and the lower back arches to supply the rest. The sensation of stretch arrives, so it feels like it worked, but the length was taken from the spine rather than the hip.
The fix is to tuck the tailbone under before you move anything else, so the pelvis is rolled back and the lower back is flat. Then move forward only a little. It will feel like a much smaller stretch and it is reaching much more of the muscle. That is not a style preference; it is the one variable a 2024 crossover trial changed, and it is in the research section below.
Sitting does not shorten them, but it does teach them to object
A day at a desk holds the hip flexors in their short position for hours, and the honest account of what that does is not that the muscle becomes structurally shorter. Pooled evidence on stretching finds range of motion improves without fascicle length changing, which points at tolerance and stiffness rather than architecture. The practical version: the muscle has not shrunk, it has learned to complain earlier.
That is good news for how you use this page. Short and frequent beats long and occasional. Sixty seconds a side, most days, in the version where you can breathe, will move it further than a punishing session on a Sunday.
The other half of the job is behind you
The hip flexors sit at the front. What holds the hip in extension, the position they are being asked to allow, is behind: the glutes and the hamstrings. A hip that will not extend is often a hip whose back side is not pulling its weight, and stretching the front on its own leaves that untouched.
So the second half of the sequence is bridges. They are not filler and they are not a cool-down. They are the reason the range you gain from the first half is still there next week.
The sequence
- 1
Lower body warm up, standing · 3 to 4 minutes
A hip that has already moved through its range accepts a held stretch far better than a cold one, and this takes about as long as it takes to stop rushing.
- 2
Low lunge, hands on a chair · 30 to 60 seconds each side
The place to start, and for many people the place to stay. Hands on the chair keep the torso upright, which is the single adjustment that stops the lower back arching to supply range the hip will not give.
- 3
Low lunge, padding under the back knee · 30 to 60 seconds each side
The half-kneeling position with the knee looked after. Kneeling on a hard floor makes people rush the stretch, and rushing is how the tuck gets skipped.
- 4
Low lunge, short stance, tailbone tucked · 30 to 60 seconds each side
This is the trial's position. Tuck the tailbone under first so the lower back flattens, then move forward barely at all. Less range at the front of the hip and more of the muscle actually reached.
- 5
Low lunge, full · 30 to 60 seconds each side
The full version, once the tuck holds without effort. If the lower back arches the moment you sink in, this is not yet the one to be doing.
- 6
Warrior I, chair supported · 30 to 45 seconds each side
The same front-of-hip position taken standing, which suits anyone who would rather not get down to the floor and back up again.
- 7
Sphinx · 60 to 90 seconds
Front of the body opened with the hips staying on the floor, so the psoas lengthens without a single-leg position to balance in. Low effort and easy to hold long enough to matter.
- 8
Bridge, small lift · 8 to 10 slow repetitions
The back of the hip starting to work. A small lift done well is worth more here than a high one done with the lower back.
- 9
Bridge, held · 3 holds of 15 to 20 seconds
Hip extension under load, which is the position the front of the hip has just been asked to allow. This is what keeps the range you gained.
- 10
Bridge with a block between the knees · 8 to 10 repetitions
The block stops the knees drifting apart, so the work stays in the glutes and the inner thigh rather than escaping into the lower back.
Take the lunges in order and stop at the first one where you can hold the tuck and still breathe normally. That is your version for now. The bridges at the end are not optional extras; they are the half of the job the stretching does not do.
What the research says
There is no clinical guideline that prescribes hip flexor stretches, and it is worth saying so plainly rather than dressing a general exercise recommendation up as a specific one. What can be sourced is how to do the stretch, what stretching actually changes, and how much of it to do.
On how, a 2024 randomized crossover trial compared the conventional half-kneeling stretch, which advances the pelvis forward, against the same position performed with a posterior pelvic tilt. Across 26 healthy active adults the posterior pelvic tilt version reduced reactive hip flexor force significantly more, by a mean of 4.85 newton metres, while the conventional version produced no significant change. Both were equivalent on a knee extension measure. It is a small trial in young healthy people rather than a definitive one, so it is offered here as the reason for a technique cue and not as a promise about symptoms.
On what stretching changes, a 2025 systematic review with meta-analysis pooling sixty-five studies found that neither a single session nor a course of static stretching significantly altered muscle fascicle length. Range of motion improved anyway, tracking reduced stiffness and greater tolerance to passive tension. On dose, the American College of Sports Medicine's position stand recommends flexibility work for each major muscle and tendon group totalling about sixty seconds per exercise, on two or more days a week, which is where the timings below come from.
Sources
- 1González-de-la-Flor et al., comparison of two different stretching strategies to improve hip extension mobility in healthy and active adults, a crossover clinical trial (BMC Musculoskeletal Disorders, 2024)
In 26 healthy active adults, a half-kneeling hip flexor stretch performed with a posterior pelvic tilt reduced reactive hip flexor force significantly more than the conventional version that advances the pelvis forward, with no difference between them on active knee extension.
- 2Mechanisms underlying range of motion improvements following acute and chronic static stretching, systematic review with meta-analysis (Sports Medicine, 2025)
Neither acute nor chronic static stretching significantly changed fascicle length; range of motion gains were associated with reduced overall stiffness and increased tolerance to passive tension.
- 3American College of Sports Medicine position stand, quantity and quality of exercise for apparently healthy adults (Garber et al., Medicine and Science in Sports and Exercise, 2011)
Adults should do a series of flexibility exercises for each of the major muscle and tendon groups, totalling 60 seconds per exercise, on two or more days a week.
Common questions
Why do I feel my hip flexor stretch in my lower back?
Almost always because the pelvis has tipped forward and the lower back is arching to supply range the hip has run out of. Tuck the tailbone under first so the lower back flattens, then move forward only slightly. The stretch will feel smaller and reach more of the muscle. Starting with hands on a chair makes the tuck much easier to hold.
Should the back knee be bent or straight?
Bent, if you want the whole group. The rectus femoris crosses the knee as well as the hip, so a straight back leg misses it. A half-kneeling position with the back knee down and bent reaches the psoas, the iliacus and the rectus femoris together.
How long do I need to hold a hip flexor stretch?
The American College of Sports Medicine's guidance works out at around sixty seconds per exercise in total, on two or more days a week. That can be one sixty-second hold or two of thirty. Frequency matters more than heroics in any single session.
Does sitting all day actually shorten the hip flexors?
Not structurally, on the current evidence. Pooled studies of stretching find range of motion improves without muscle fascicle length changing, which points at stiffness and tolerance rather than the muscle becoming shorter. Practically it means the range comes back with regular short sessions rather than requiring you to undo months of damage.
Do I need to strengthen as well as stretch?
It is the part most routines leave out. The hip flexors sit at the front; what holds the hip in extension is the glutes and hamstrings behind. If the back of the hip is not working, the range gained at the front tends not to stay. That is why this sequence ends in bridges.
Front-of-hip discomfort that is sharp, that catches or clicks painfully as you move through the range, or that came on after a specific incident, is worth having looked at rather than stretched. The same goes for groin pain that does not settle. Stop and speak to a clinician if a movement brings on sharp pain, dizziness, or symptoms that travel down an arm or a leg, and seek urgent care for any loss of bladder or bowel control or numbness around the saddle area.
Also called hip flexor stretches, hip flexor stretch, stretches for tight hip flexors, hip flexor stretches for lower back pain, best hip flexor stretch, hip flexor stretches from sitting. Movements are drawn from the clinically authored Vinys library. This page is general movement information, not medical advice, and it is not a diagnosis. How the method works.