Do Tight Hip Flexors Cause Back Pain?

There's a whole genre of videos right now telling you that one tight muscle is the reason your back hurts. They say releasing tension in the psoas muscle will make your back pain go away. I regularly see posts pointing towards a single cause for back pain. They typically get a lot of views or interactions. The marketing pitch is really strong: “do this one thing and your pain will go away.”

The interesting part is that tight hip flexors are linked to back pain. A 2026 study measured the injury rates of hockey players over four seasons. The ones with tight hip flexors had roughly three times the rate of back pain [1]. So there’s something here that’s worth looking at.

TLDR

• Hockey players with tight hip flexors had 3x the rate of back pain vs those without over the span of 4 seasons. Hip strength didn’t predict injury rates.
• Stretching acutely reduces muscle tension.
• Psoas helps stabilize your spine. Excessive tightness may be linked to prolonged sitting.
• Daily stretching and regularly interrupting sitting can help reduce tightness.

Hip flexors

Last week we covered the SI joint. This week, we’re nearby and talking about the muscles that help perform hip flexion: the action of decreasing the distance between your trunk and your thighs. Picture someone performing a “high knees” warm up exercise. The muscles that raise their thighs into the air are the hip flexors.

The main hip flexor muscles are:

• Psoas major - the main hip flexor that everyone talks about
  • Fun fact #1: psoas minor sits alongside psoas major but does not actually help flex the hip AND only 40-60% of people even have this muscle
• Iliacus - sits inside your pelvis and joins to psoas major (together often called iliopsoas)
• Rectus femoris - one of your quad muscles that crosses the hip and helps with hip flexion
  • That’s why doing situps can give you a bit of a quad stimulus
• A few smaller muscles contribute as well like pectineus and sartorius
  • Fun fact #2: sartorius is the longest muscle in the body

The reason why psoas major is so relevant to the spine is because its proximal attachment is the vertebrae of our lumbar spines and then it runs along the front of our pelvis to the top of our femurs. So when we sit in hip flexion, this muscle is shortened. And for many of us, it’s in that position for most of the day. If the muscle is really tight, then it can tip the pelvis forward when we stand up and cause ‘anterior pelvic tilt’.

Whether or not this tilt is a problem is a hotly debated topic, but it is anatomically correct to state that excessive anterior pelvic tilt forces the lumbar spine into greater lordosis. Spoiler: everyone has different degrees of natural lordosis. So the curvature of one spine can be different from another without causing any issues. I’ve mentioned this before in a previous newsletter but this posture is described perfectly by imagining someone that tries to stick their butt out by arching their low back a lot.

Some evidence…finally

A 2026 study measured hip flexor tightness in three hockey teams every preseason for four years [1]. Hip tightness was measured using the Thomas test where you lie on your back, pull one knee towards your chest, and then measure the angle between the table and the other leg (larger = tighter hips). Of the players with tight hip flexors, ~16% went on to miss games with back pain compared to only 5% in those without tight hips. Hip strength was not predictive of back pain in the players. A note on that: a muscle can be tight and weak at the same time. So a tight muscle is not always one that just needs to be stretched and ignored (can often benefit from strengthening too).

Another thing: skating requires a lot of hip flexion. Skating for hours each week increases the potential for tight hip flexors and strain on the lower back. While this study found an interesting relationship, it is just that. It's still just one sport and an association (not a causal relationship), so treat it as a signal.

So what about stretching?

A study had 23 men do a single session of hip flexor stretching and measured their pelvic positions before and after [2]. There was a difference…kind of. Passive hip extension increased by 2.6 degrees and anterior pelvic tilt decreased 1.2 degrees. Lower back postures didn’t change at all. This was just a simple pre-post examination of one stretching session.

Another study took a more comprehensive approach. They measured the movements of the pelvis and lower back during running before and after three weeks of hip flexor stretching [3]. They gained range of motion in their hips when they were passively moved through hip flexion and extension, but their pelvic and lower back movements were the same as before when running. So stretching can reduce tension at rest, but that increased flexibility may not translate to altered movement mechanics when a whole host of other muscles are engaged.

But does that really matter? If stretching helps people, then that is enough. A trial randomized 40 professional footballers with chronic low back pain to eight weeks of dynamic hip flexor stretching or normal training [4]. Back pain dropped in the stretching group. The study then had them stop stretching for four weeks and pain returned in some of the players.

So the stretching helps acutely. That’s great news, but it also means that if it’s going to help, it has to be done regularly.

The role of hip flexors

Due to their attachment points, the hip flexors, especially psoas major, function to stabilize the spine and not just flex the hips. There’s plenty of other muscles that work together to achieve spinal stability. So, with that in mind, an ideal approach is to stretch the hip flexors while also strengthening all of the muscles that contribute to spinal stability. I know…what a shocker, Mitch is recommending strengthening the muscles of the trunk and hips again.

The evidence for that comes from a 2025 meta-analysis of people with chronic low back pain [5]. Resistance training of the trunk and hips gave the biggest and most consistent improvement in function. The answer is both stretching and strengthening. A muscle can be weak whether it is loose or tight. We want stability from strength and mobility without excessive muscle tightness.

What I'd actually do

1. Stretch, short and daily. Half-kneeling hip flexor stretch:
   • Kneel on one knee with the other foot flat in front of you, both knees at roughly 90 degrees.
   • Squeeze the glute of your kneeling leg, tighten your lower abs, and push your pelvis forward slightly. Don't arch your back, remain upright.
   • Lift the arm on your kneeling-leg side straight up toward the ceiling, keeping your ribs down.
   • Lean slightly deeper into the stretch (pain permitting) while maintaining a neutral spine. A subtle lean toward the opposite side can increase the stretch.
   • One or two rounds of 20-30 seconds per side, once a day. Up to two minutes of hip flexor stretching doesn't cost you strength or power, so it's fine to do anytime around exercise [6]. If you’re worried that stretching the hips before exercise may make your hips and spine feel unstable, no problem: stretch after.
2. Break up your sitting. I know, I’ve said this a million times but it really does help with so many dimensions of health.
3. Strengthen the muscles of the trunk/core and hips. Glute bridges at home or hip thrusts in the gym. Seated good mornings, then bodyweight hip hinges, then Romanian deadlifts as you get stronger. Dead bugs/front planks and side planks for the core.

If you want a program that takes care of all of this, and helps you avoid the traps of your specific pattern of back pain, take my free 2-minute quiz to get started.

Beware: additional stretches for your hamstrings and hips might make your back pain worse. If you suffer from sciatica symptoms, avoid stretches like seated hamstring and figure-4 stretches. I wrote a previous newsletter on this that you can read here.

As always, have a great weekend.

Best,

Mitch

References

[1] McHugh et al., 2026. The Association Between Hip Flexibility and Low Back Pain in Ice Hockey Players. Orthopaedic Journal of Sports Medicine, 14(2). doi:10.1177/23259671251404068

[2] Preece et al., 2021. Comparison of Pelvic Tilt Before and After Hip Flexor Stretching in Healthy Adults. Journal of Manipulative and Physiological Therapeutics, 44(4), 289-294. doi:10.1016/j.jmpt.2020.09.006

[3] Mettler et al., 2019. Effects of a Hip Flexor Stretching Program on Running Kinematics in Individuals With Limited Passive Hip Extension. Journal of Strength and Conditioning Research, 33(12), 3338-3344. doi:10.1519/JSC.0000000000002586

[4] Iranmanesh et al., 2025. The training and detraining effects of 8-week dynamic stretching of hip flexors on hip range of motion, pain, and physical performance in male professional football players with low back pain. Journal of Sports Sciences, 43, 1572-1586. doi:10.1080/02640414.2025.2513163

[5] Guo et al., 2025. Effects of different types of core training on pain and functional status in patients with chronic nonspecific low back pain: a systematic review and meta-analysis. Frontiers in Physiology, 16, 1672010. doi:10.3389/fphys.2025.1672010

[6] Konrad et al., 2021. The Influence of Stretching the Hip Flexor Muscles on Performance Parameters. A Systematic Review with Meta-Analysis. International Journal of Environmental Research and Public Health, 18(4), 1936. doi:10.3390/ijerph18041936

Disclaimer: this content is educational only and does not constitute medical advice. See a practitioner if you suspect serious spinal trauma from a fall or accident, or if you experience any of the following red flag symptoms: loss of bowel or bladder control, numbness in the groin or saddle area, rapidly worsening leg weakness, back pain with fever or feeling generally unwell, or unexplained weight loss with back pain.