Hip flexor stretch

Movement

The position

The hip flexors are the muscles that bend the hip. The psoas major and the iliacus together make up the iliopsoas group⁷. The iliopsoas is the primary flexor of the thigh at the hip⁸.

The authors of one study describe the most used hip flexor stretch as half-kneeling¹. The back knee rests on the ground and the pelvis moves forward¹. In that study’s conventional version, participants knelt on one knee with the other foot forward¹. They shifted the pelvis gently forward with a neutral spine and an upright trunk¹. The aim was to feel the stretch at the front of the kneeling leg’s hip, without arching the lower back¹.

Why the pelvis matters

With the femur (thigh bone) fixed, the psoas major and the iliacus together tilt the pelvis forward⁹. The same study’s authors state that people often make up for limited hip extension by tilting the pelvis further forward¹. They add that the usual half-kneeling stretch works on hip extension without addressing pelvic tilt¹.

So the study tested a second version, done with a posterior pelvic tilt¹. That means tucking the tailbone under, rocking the top of the pelvis back. Participants held that tuck while moving the pelvis forward¹. They used the lower abdominal muscles and the gluteus maximus (the large muscle of the buttock) to limit forward tilt¹. Each version was done as two sets of 30 seconds¹.

The rectus femoris and the back knee

The rectus femoris is the quadriceps muscle at the front of the thigh that also bends the hip. It crosses two joints, the hip and the knee¹⁰. One study’s authors describe it as the one quadriceps muscle stretched by hip extension combined with a knee bend¹¹. The quadriceps stretch page covers that combination.

How studies measure the result

Several studies on this page measured passive hip extension on a Thomas test or a modified Thomas test^2,12. Passive means moved by an outside force, with no effort from the person. In 29 healthy college students, the modified test was a poor measure of peak hip extension when pelvic tilt was not controlled¹². It appeared valid when tilt was controlled¹².

What it loads

Hip extension puts load on more than muscle^7,13:

• Iliacus. One study measured this muscle’s stiffness, in 26 healthy men, with shear wave elastography¹⁴. That is an ultrasound method that estimates how stiff a tissue is.
• Rectus femoris. In 20 healthy participants, hip extension stiffened the upper, hip-end region of this muscle¹⁵.
• Hip ligaments. The ligaments of the hip joint tighten when the hip extends, and allow very little extension beyond upright standing⁷.
• Femoral nerve. A cadaver study measured tension on 6 femoral nerves¹³. Tension was greater with the hip extended than with the leg pulled into traction¹³.

The gluteus maximus has been measured too. One study tested 25 people with a short iliopsoas lifting the leg back while lying face down¹⁶. Gluteus maximus activity was greater, and forward pelvic tilt lower, when the exercise followed iliopsoas stretching¹⁶.

How the body adapts

Straight after one session

Stiffness is how much force it takes to stretch something by a given amount. In the 26 healthy men, iliacus stiffness was lower after a single 1-minute static (held) hip extension stretch than before it¹⁴.

In 23 men, one session of passive stretching of the hip flexors was followed by three measured results²:

• Passive hip extension on a Thomas test rose by a mean 2.6 degrees².
• Forward pelvic tilt fell by a mean 1.2 degrees, which the authors relate to relaxed standing².
• Lumbar lordosis (the inward curve of the lower back) did not change². The change in hip extension was not meaningfully correlated with the change in pelvic tilt or lordosis².

Sixteen Australian Rules footballers added 4.5 minutes of static hip flexor and quadriceps stretching to a running warm-up¹⁷. Their flexibility on a modified Thomas test did not change significantly¹⁷. The authors suggest the test may not have been sensitive to short-term changes¹⁷. Across stretching in general, one review found the gain after a session typically lasts less than 30 minutes¹⁸.

The two versions compared

A crossover trial is a study in which each person tries every option in turn. One such trial, with the order set by chance, compared the two half-kneeling versions in 26 healthy, physically active adults¹. The version with a posterior pelvic tilt lowered reactive hip flexor force by a mean 4.85 newton-metres, a unit of turning effect¹. The conventional version changed it by 0.06 newton-metres¹. The authors say that testing young, healthy, active people limits how far the findings apply to sedentary or recently injured people¹.

Sprint, jump and strength tests

A systematic review with meta-analysis pooled eight studies, with 165 subjects, of a single hip flexor stretching exercise and performance³. A meta-analysis is a study that pools the results of several earlier studies. This one took in studies of healthy, pain-free people that stretched the hip flexors alone³. Its authors note that the evidence rests on a small number of studies³.

The review concluded that up to 120 seconds of isolated hip flexor stretching seems to have no effect, or even a positive one, on performance³. Longer stretching came with a larger change, as this table shows³:

Stretch duration	Weighted mean change in performance
30 to 90 seconds	-0.12%3
270 to 480 seconds	-3.59%3

The difference between those durations was significant³. The eight studies took 43 performance measures: 5 improved, 21 did not change and 17 were impaired³. The impaired measures all came from isokinetic tests, strength tests on a machine that holds a limb to a fixed speed³.

Over weeks: range rose, movement often did not

Five trials that placed people in groups by chance ran programmes of 3 to 10 weeks^5,6,19,20,21:

Who and how long	Hip extension range	Walking, running or other movement
25 healthy, athletic male college students, 3 weeks	Right hip improved from -20.4 to -8.3 degrees, left from -16.8 to -7.05	No significant change in walking or running economy (oxygen use at a set speed)5
24 healthy young men with limited hip mobility, 6 weeks	Large gains in passive hip range6	No more hip range used in active standing hip extension, a lunge, a twist-and-reach or elliptical trainer exercise6
96 healthy elderly people, 10 weeks, on their own	Static peak hip extension rose from 6.1 to 7.7 degrees19	Hip extension in walking tended to rise, but not significantly19
82 healthy elderly people, 10 weeks, supervised	Passive hip extension improved significantly20	Stride length and peak hip extension rose in those who began with limited hip extension in walking20
74 frail elderly people, 10 weeks, supervised	Passive hip extension increased21	Walking speed and stride length increased; peak hip extension and forward pelvic tilt in walking did not change significantly21

In 20 healthy subjects with limited passive hip extension, 3 weeks of hip flexor stretching raised that range, but not their hip extension in running⁴. The programme was done at home, and forward pelvic tilt and lumbar spine extension during submaximal running did not change either⁴.

In 20 healthy subjects with limited passive hip extension, 3 weeks of hip flexor stretching raised that range, but not their hip extension in running.

After stopping

One trial followed 40 professional male football players with chronic low back pain for 4 weeks after 8 weeks of dynamic hip flexor stretching²². The stretching group’s gains in hip range of motion and pain scores were partly, but significantly, lost²². The detraining page covers what stopping does more broadly.

In people with low back pain

Two trials tested stretching in people who already had low back pain^22,23:

• Thirty women with non-specific low back pain were assigned by chance to 8 weeks of stretching sessions or a control group²³. Disability, pain and passive hip range improved from before to after in the stretching group²³. The group-by-time interaction was not significant for any outcome²³. The authors note that with no placebo (dummy) comparison, the improvement may relate to a placebo effect²³.
• In the trial of 40 football players, groups were set by chance, and one did supervised dynamic stretching five times a week²². That group improved significantly in hip range, pain, dynamic balance and countermovement jump, a jump that starts with a quick dip²². Sprint time over 20 metres and agility test performance did not improve significantly²².

Dynamic stretching is described as a controlled movement through a joint’s range of motion²⁴.

Progressive overload

Progressive overload is the subject of its own page. The studies of this stretch differed in time under stretch, in repetitions and rest, and in supervision^14,19,23.

Time under stretch in one session

In the 26 healthy men, a 1-minute static hip extension stretch was done five times¹⁴. Iliacus stiffness was lower after the fifth stretch than after the first¹⁴. The review above compared durations too. At its longest durations, 270 to 480 seconds, the pooled fall in performance was statistically significant but trivial³. At its shortest, 30 to 90 seconds, no significant fall was found³.

Repetitions and rest across a programme

The 8-week programme in women with non-specific low back pain included a half-kneeling stretch, with padding under the knee²³. It was held for 30 seconds, with 8 seconds of rest, for 10 repetitions, three times a week²³. Exercises started at a low level²³. They were progressed by adding repetitions and shortening rest, within each participant’s tolerance and without pain or fatigue²³.

Supervision

In the trial of 96 healthy elderly people, participants had one instruction session and then stretched on their own twice daily¹⁹. The authors named that as a limitation, and suggested a more rigorous, supervised programme might change walking more¹⁹.

What reviews of stretching in general say

Reviews of stretching programmes across muscle groups disagree on dose. One meta-analysis of static stretching found larger flexibility gains with more repetitions and more time under stretch²⁵. Another, of 77 studies, found no relationship between the range gained and total stretch duration or weekly frequency²⁶. The stretching page sets those reviews side by side.

Connections

The structures it reaches

The stretch works on hip extension, and the hip flexors, led by the iliopsoas, flex the thigh at the hip^1,8. So does the rectus femoris, part of the quadriceps¹⁰. The ligaments of the hip joint tighten in extension, and a cadaver study found tension on the femoral nerve greatest with the hip extended^7,13. The version with the pelvis tucked under uses the gluteus maximus¹.

Flexibility and later hip flexor strains

One prospective study, which follows people forward in time, measured range before injuries happened²⁷. Thirty-six elite male soccer players were followed for a season²⁷. Those who went on to strain a hip flexor or knee flexor had lower preseason range in those muscle groups than uninjured players²⁷. The hip flexor strain page covers that injury.

Sources

1. González-de-la-Flor Á, Cotteret C, García-Pérez-de-Sevilla G, Domínguez-Balmaseda D, Del-Blanco-Muñiz JÁ (2024). Comparison of two different stretching strategies to improve hip extension mobility in healthy and active adults: a crossover clinical trial.. BMC musculoskeletal disorders. doi:10.1186/s12891-024-07988-9 PMID 39462416
2. Preece SJ, Tan YF, Alghamdi TDA, Arnall FA (2021). Comparison of Pelvic Tilt Before and After Hip Flexor Stretching in Healthy Adults.. Journal of manipulative and physiological therapeutics. doi:10.1016/j.jmpt.2020.09.006 PMID 34090549
3. Konrad A, Močnik R, Titze S, Nakamura M, Tilp M (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. doi:10.3390/ijerph18041936 PMID 33671271
4. Mettler JH, Shapiro R, Pohl MB (2019). Effects of a Hip Flexor Stretching Program on Running Kinematics in Individuals With Limited Passive Hip Extension.. Journal of strength and conditioning research. doi:10.1519/JSC.0000000000002586 PMID 29927892
5. Godges JJ, MacRae PG, Engelke KA (1993). Effects of exercise on hip range of motion, trunk muscle performance, and gait economy.. Physical therapy. doi:10.1093/ptj/73.7.468 PMID 8316580
6. Moreside JM, McGill SM (2013). Improvements in hip flexibility do not transfer to mobility in functional movement patterns.. Journal of strength and conditioning research. doi:10.1519/JSC.0b013e318295d521 PMID 23591949
7. Betts JG, Young KA, Wise JA, Johnson E, Poe B, Kruse DH, Korol O, Johnson JE, Womble M, DeSaix P (2022). Anatomy and Physiology 2e. OpenStax. Link
8. Bordoni B, Varacallo MA (2026). Anatomy, Bony Pelvis and Lower Limb: Iliopsoas Muscle.. StatPearls. PMID 30285403
9. Gray H; Lewis WH (editor) (1918). Anatomy of the Human Body. Lea & Febiger, Philadelphia (20th edition). Link
10. Begum FA, Kayani B, Chang JS, Tansey RJ, Haddad FS (2020). The management of proximal rectus femoris avulsion injuries.. EFORT Open Reviews. doi:10.1302/2058-5241.5.200055 PMID 33312709
11. Hirono T, Yagi M, Wang Z, Sakata H, Okada S, Nakazato K, Ichihashi N, Watanabe K (2025). Selective Static Stretching of Rectus Femoris Alters Motor Unit Firing Behaviors of Knee Extensors.. Scandinavian journal of medicine & science in sports. doi:10.1111/sms.70031 PMID 40012478
12. Vigotsky AD, Lehman GJ, Beardsley C, Contreras B, Chung B, Feser EH (2016). The modified Thomas test is not a valid measure of hip extension unless pelvic tilt is controlled.. PeerJ. doi:10.7717/peerj.2325 PMID 27602291
13. Livingstone JP, Tamate TM, Richardson AK, Harpstrite JK (2022). A Cadaveric Study Measuring Femoral Nerve Tension During Anterior Total Hip Arthroplasty Approach.. Hawai'i journal of health & social welfare. PMID 35340935
14. Nojiri S, Yagi M, Mizukami Y, Ichihashi N (2019). Static stretching time required to reduce iliacus muscle stiffness.. Sports biomechanics. doi:10.1080/14763141.2019.1620321 PMID 31232167
15. Ley CD, Valdes EM, Murtagh CF, Power J, Drust B (2026). Regional Differences in Muscle and Fascial Tissue Stiffness in the Rectus Femoris Are Dependent Upon Localised Stretching.. European journal of sport science. doi:10.1002/ejsc.70109 PMID 41741933
16. Park KY, Jeon IC, Hwang UJ, Jung SH, Ha SM, Yim SY (2022). Effects of abdominal drawing-in maneuver with or without prior iliopsoas stretching on gluteus maximus activity during prone hip extension.. Journal of back and musculoskeletal rehabilitation. doi:10.3233/BMR-200251 PMID 34250929
17. Young W, Clothier P, Otago L, Bruce L, Liddell D (2004). Acute effects of static stretching on hip flexor and quadriceps flexibility, range of motion and foot speed in kicking a football.. Journal of science and medicine in sport. doi:10.1016/s1440-2440(04)80040-9 PMID 15139161
18. Behm DG, Blazevich AJ, Kay AD, McHugh M (2016). Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review.. Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme. doi:10.1139/apnm-2015-0235 PMID 26642915
19. Kerrigan DC, Xenopoulos-Oddsson A, Sullivan MJ, Lelas JJ, Riley PO (2003). Effect of a hip flexor-stretching program on gait in the elderly.. Archives of physical medicine and rehabilitation. doi:10.1053/apmr.2003.50056 PMID 12589613
20. Watt JR, Jackson K, Franz JR, Dicharry J, Evans J, Kerrigan DC (2011). Effect of a supervised hip flexor stretching program on gait in elderly individuals.. PM & R : the journal of injury, function, and rehabilitation. doi:10.1016/j.pmrj.2010.11.012 PMID 21497318
21. Watt JR, Jackson K, Franz JR, Dicharry J, Evans J, Kerrigan DC (2011). Effect of a supervised hip flexor stretching program on gait in frail elderly patients.. PM & R : the journal of injury, function, and rehabilitation. doi:10.1016/j.pmrj.2011.01.006 PMID 21497319
22. Iranmanesh M, Shafiei Nikou S, Saadatian A, Alimoradi M, Khalaji H, Monfaredian O, Saki F, Konrad A (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. A randomized controlled trial.. Journal of sports sciences. doi:10.1080/02640414.2025.2513163 PMID 40465522
23. Hatefi M, Babakhani F, Ashrafizadeh M (2021). The effect of static stretching exercises on hip range of motion, pain, and disability in patients with non-specific low back pain.. Journal of experimental orthopaedics. doi:10.1186/s40634-021-00371-w PMID 34318348
24. Behm DG, Alizadeh S, Daneshjoo A, Anvar SH, Graham A, Zahiri A, et al. (2023). Acute Effects of Various Stretching Techniques on Range of Motion: A Systematic Review with Meta-Analysis.. Sports medicine - open. doi:10.1186/s40798-023-00652-x PMID 37962709
25. Arntz F, Markov A, Behm DG, Behrens M, Negra Y, Nakamura M, Moran J, Chaabene H (2023). Chronic Effects of Static Stretching Exercises on Muscle Strength and Power in Healthy Individuals Across the Lifespan: A Systematic Review with Multi-level Meta-analysis.. Sports medicine (Auckland, N.Z.). doi:10.1007/s40279-022-01806-9 PMID 36719536
26. Konrad A, Alizadeh S, Daneshjoo A, Anvar SH, Graham A, Zahiri A, et al. (2024). Chronic effects of stretching on range of motion with consideration of potential moderating variables: A systematic review with meta-analysis.. Journal of sport and health science. doi:10.1016/j.jshs.2023.06.002 PMID 37301370
27. Bradley PS, Portas MD (2007). The relationship between preseason range of motion and muscle strain injury in elite soccer players.. Journal of strength and conditioning research. doi:10.1519/R-20416.1 PMID 18076233

Every source the library cites

Changes

• October 7, 2026 First published.