Strengthening your hip flexors starts with targeted exercises that activate the deep muscles connecting your spine to your legs. These muscles do more than lift your knees. They stabilize your lower back, support your posture while sitting, and power every step you take up a staircase. Weak hip flexors are surprisingly common, especially in people who sit for long periods, and the fix is straightforward once you know which exercises actually work.
What Your Hip Flexors Actually Do
The hip flexor group is anchored by the iliopsoas, a combination of the psoas major (which runs from your lower spine) and the iliacus (which lines the inside of your pelvis). Together they pull your thigh toward your torso. That single action drives walking, running, climbing stairs, and getting out of a chair. But these muscles also act as stabilizers: they hold your lower back steady when you sit, keep your pelvis level when you stand on one leg, and help your core transfer force between your upper and lower body.
The rectus femoris, one of your four quadriceps muscles, also crosses the hip joint and assists with flexion. It tends to take over when the deeper iliopsoas is weak, which is one reason people can feel hip flexor fatigue in the front of their thigh rather than deep in the hip.
Tight vs. Weak: How to Tell the Difference
Tightness and weakness often coexist in the hip flexors, and they can produce similar symptoms: low back pain after sitting, a sensation of stiffness when you stand up, and general discomfort around the hips. But they aren’t the same problem. Tight hip flexors tilt your pelvis forward, creating an exaggerated curve in your lower back (sometimes called hyperlordosis). Weak hip flexors compromise core strength and alignment throughout the body. You may have both issues at once, which is why stretching alone rarely solves the problem.
Two simple self-tests can help you figure out what you’re dealing with:
- Thomas test (for tightness): Sit on the edge of a sturdy table or bench with your feet flat on the floor. Lie back and hug both knees to your chest. Then slowly release one leg and let it lower toward the starting position. If your foot can reach the table surface while you keep the other knee hugged in, that side passes. Test both legs.
- Standing hold test (for strength): Stand with feet shoulder-width apart. Raise one knee and hug it to your chest. Release your hands and use only your hip flexors to hold the knee in place. If your knee drops immediately or you can’t maintain the position for at least 10 seconds, that hip flexor is weak.
Why Weakness Matters Beyond the Hip
Weak hip flexors don’t just make it harder to lift your legs. Because the psoas attaches directly to your lumbar spine, weakness there removes a key stabilizer from your lower back. Your body compensates by shifting load to the spinal erectors and other back muscles, which weren’t designed to carry that burden alone. The result is often chronic low back pain that doesn’t respond to back-focused treatments, because the real problem is at the hip.
Pelvic tilt is the other consequence. When the hip flexors can’t hold the pelvis in a neutral position, it drifts forward, flattening the glutes, shortening the lower back muscles, and creating a posture that loads the lumbar discs unevenly. Strengthening the hip flexors directly addresses this chain of compensation.
The Best Exercises for Hip Flexor Strength
Research measuring muscle activation during common exercises consistently shows that straight leg raises and standing hip flexion produce the highest demand on the psoas. A review of EMG studies found that holding a straight leg raise at 60 degrees generated about 61 to 67 percent of maximum voluntary contraction in the psoas major, making it one of the most effective positions for building strength in that muscle. Standing on one leg while holding the opposite hip flexed to 90 degrees produced the highest raw muscle activation of any exercise measured.
Here are the exercises worth building a routine around, ordered from beginner to more advanced:
Supine Straight Leg Raise (Hold)
Lie on your back with one leg bent and the foot flat on the floor. Lift the straight leg to roughly 45 to 60 degrees and hold for 5 to 10 seconds. The higher the angle and the longer the hold, the greater the psoas activation. Start with 45 degrees and work up. This is the single most supported exercise for deep hip flexor strengthening.
Standing Knee Hold
Stand tall and lift one knee to hip height (90 degrees). Hold it there without using your hands. Aim for 10 seconds per side to start, building toward 20 to 30 seconds. This exercise forces the hip flexor to work against gravity while your standing leg and core stabilize. It also doubles as a balance challenge.
Psoas March With Resistance Band
Loop a resistance band around both feet. Lie on your back with both hips and knees bent to 90 degrees. Press one leg down straight to the floor while resisting the pull of the band on the opposite leg. Return to the starting position and alternate. The band forces both hip flexors to work simultaneously, one eccentrically (lowering) and one isometrically (holding), which builds strength across the full range of motion.
Banded Pseudo Running
Attach a resistance band to a stable object at ankle height and loop it around one ankle. Face away from the anchor point. Drive your knee up into hip flexion against the band’s resistance, then slowly extend the leg back and lower it down. This mimics the hip flexion pattern of running and is particularly useful for athletes. The slow lowering phase builds tendon resilience in addition to muscle strength.
Sets, Reps, and How Often to Train
The UCSF Orthopaedic Institute’s hip strengthening protocol recommends 3 sets of 10 to 15 repetitions, performed 3 times per week. That volume applies well to banded exercises and dynamic movements like the psoas march. For isometric holds (the straight leg raise hold and standing knee hold), aim for 3 sets of 5 to 10 second holds per side, progressing to longer holds as you get stronger.
Three sessions per week gives the muscles enough stimulus to adapt while allowing 48 hours of recovery between sessions. You can add hip flexor work to the end of a regular workout or do it as a standalone 10 to 15 minute routine on rest days. Consistency matters more than volume here. Two months of three-times-weekly training is enough for most people to notice meaningful improvements in strength, posture, and any associated back discomfort.
How to Progress Over Time
Start with bodyweight exercises and isometric holds for the first two to three weeks. This builds baseline strength and lets you feel whether the right muscles are firing. If you notice the front of your thigh burning more than the deep crease of your hip, you’re likely compensating with the rectus femoris. Slowing down the movement and focusing on pulling from deep in the hip can help shift activation to the iliopsoas.
After the initial phase, add resistance bands. Light bands are enough at first. Progress to heavier bands as the target rep range (10 to 15) becomes easy with controlled form. From there, you can increase hold times for isometric exercises, add ankle weights to standing knee raises, or introduce hanging knee raises if you have access to a pull-up bar. The key is progressive overload: gradually increase the demand so the muscles continue adapting.
For people recovering from a hip flexor strain or dealing with significant weakness, starting with the supine straight leg raise at a lower angle (30 to 45 degrees) and shorter hold times (3 to 5 seconds) is a safer entry point. The slow, controlled lowering phase of any exercise is especially valuable for tendon health, so resist the temptation to drop the leg quickly on the way down.