Written by the Phoenix Rehab physiotherapy team.Clinically reviewed by Louise Yow, Principal Physiotherapist and Director, AHPC A1300363H.Last reviewed 4 October 2026.
A hip flexor strain is a strain or tear in the muscles at the front of the hip that lift the knee, usually from a hard sprint, a kick or a sudden lunge. It hurts at the crease of the hip when you lift the knee, climb stairs or get in and out of a car. Most mild strains settle in two to four weeks. Front-of-hip pain has other causes too, and some of them should not be stretched or run through.
Where is hip flexor pain felt?
At the front of the hip, in the crease where the thigh meets the body, sometimes a little lower down the front of the thigh. It is worse lifting the knee against resistance, sprinting, kicking and climbing stairs. A strained rectus femoris, the hip flexor that also crosses the knee, often hurts when the knee is bent and the hip is pulled back at the same time.
Is it the hip flexor, or something else?
| What you notice | More likely | Read more |
|---|---|---|
| Started with a sprint or kick, sore to lift the knee, tender at the front | Hip flexor strain | This page |
| Deep pinch in the groin when you squat deep or sit low, sometimes catching or clicking | The hip joint: impingement or a labral tear | Hip impingement · Hip labral tear |
| Pain on the inner thigh with kicking or changing direction | Adductor strain or other groin causes | Groin pain |
| A clunk at the front of the hip lowering the leg | Snapping hip | Snapping hip |
| Deep groin pain that comes on during runs and builds, in a runner who has been adding kilometers | Possible stress fracture of the thigh bone | Stop running. See a doctor the same day. Stress fracture |
Should you stretch a strained hip flexor?
Not hard, and not early. A fresh tear does not need pulling apart. In the first week or two, keep moving within comfort and let the pain settle. The hip flexor stretch has its place later. People with front-of-hip pain who stretch every day without improving often have a strength problem, or a joint problem, not a short muscle.
How long does a hip flexor strain take?
| Grade | What it feels like | Usually back to sport |
|---|---|---|
| Mild | Sore, but you can walk and lift the knee | About two to four weeks |
| Moderate | A limp, weak to lift the knee, sometimes bruising | About four to eight weeks |
| Severe | Cannot lift the knee, a pop, a dent or bruising | See a doctor within days |
What we measure before you sprint and kick again
- Strength. Hip flexor strength on both sides, with the knee bent and straight.
- Range. Hip extension compared with the other side.
- Control. Single-leg balance and a step-down, because the hip flexor is often working too hard for weak gluteal muscles.
- Sport. Running speed, then kicking and changing direction, in steps.
Tested, not dated. You sprint and kick again when the measures say so. Pain is the first thing to leave. Strength is the last to train and recover.
When to see a doctor first
- Go to the emergency department now if you cannot put any weight on the leg, or the hip is hot and swollen with a fever.
- See a doctor the same day for a sudden pop at the front of the hip in a teenager sprinting or kicking, who cannot lift the leg afterward; at that age the tendon can pull a piece of bone off. Also for running-related deep groin pain, as above.
- See a doctor soon for a lump in the groin that comes and goes with coughing or straining, or pain that wakes you at night.
Where are you with this right now?
1. It is settling on its own
If stairs and the car are easier each week and you can lift the knee without a catch, keep building gently. You are probably in Stage 2 of 4.
2. It has stopped improving
Five weeks since it went in the match. You can jog. The first hard sprint, the first long kick, and it grabs at the front of the hip again. You have stretched it twice a day. The strength of the hip flexor, and of the gluteal muscles behind it, on that side, has not been measured.
WhatsApp us · Get Assessed & Treated · One 45-minute appointment, $230, nett, no GST.
3. You have had surgery, or you have a date
After hip arthroscopy, see the Hip Arthroscopy and FAI Recovery Program. All of it runs on the four stages of the Phoenix Recovery Protocol.
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