Strengthening your hip flexors comes down to exercises that challenge the muscles on the front of your hip through their full range, then progressively adding resistance over time. These muscles are involved in every step you take, every time you climb stairs, and every time you bring your knee toward your chest. Despite being some of the most used muscles in daily life, they’re rarely trained directly, which leaves many people with surprising weakness in this area.
The Muscles That Flex Your Hip
Hip flexion isn’t a one-muscle job. The primary driver is the iliopsoas, a deep muscle that connects your lower spine and pelvis to your thigh bone. It’s the strongest hip flexor and the one most responsible for lifting your leg. Working alongside it is the rectus femoris, the only quadriceps muscle that crosses both the hip and knee joints, which means it helps with hip flexion and knee extension at the same time.
A lesser-known contributor is the pectineus, a small muscle near the top of your inner thigh. It’s unique because it assists with both hip flexion and pulling the leg inward toward your midline. No other hip flexor works on both of those movements simultaneously. The tensor fasciae latae, on the outer hip, and the sartorius, which runs diagonally across the front of your thigh, also chip in during hip flexion. Strengthening the hip flexors effectively means loading all of these muscles, not just one.
Why Hip Flexor Strength Matters
Weak hip flexors create a cascade of problems. When these muscles can’t do their job, your lower back often picks up the slack, leading to excessive lumbar arching during movement. This compensation pattern is a well-documented contributor to low back pain. Prolonged sitting, cycling, and jogging can make the hip flexors tight but not necessarily strong. Tightness and weakness can coexist in the same muscle, and both create issues.
Tight hip flexors pull the front of the pelvis downward into what’s called an anterior pelvic tilt. That forward tilt changes your posture and, critically, inhibits the glutes. When your glutes stop firing properly, the imbalance between the front and back of your hip worsens, and your lower back absorbs forces it wasn’t designed to handle alone.
For athletes, hip flexor strength has a direct relationship with speed. Research on sprinters found significant correlations between hip flexion strength and sprint performance in men, with correlation values ranging from 0.51 to 0.75 across multiple testing speeds. The size of the psoas major, the deepest hip flexor, was closely tied to how much force sprinters could produce during hip flexion. Whether you’re sprinting, kicking, or just walking uphill, stronger hip flexors make your legs more powerful.
Best Exercises for Hip Flexor Strength
Not all exercises activate the hip flexors equally. A 2024 study measuring muscle activation during common rehabilitation and strength exercises found that the iliopsoas worked hardest during two movements: the active straight leg raise performed to about 60 degrees of hip flexion, and supine hip flexion (lying on your back and lifting one knee toward your chest against resistance). Both produced muscle activation above 60% of maximum voluntary contraction, the threshold generally considered effective for building strength.
Exercises performed at a mid-range position, around 45 degrees of hip flexion, and movements where you lift your trunk while your hips are bent produced moderate activation in the 40 to 60% range. These are still useful but less intense for the hip flexors specifically.
Here are the most effective exercises, ordered from beginner to advanced:
- Supine marching: Lie on your back with knees bent. Lift one knee toward your chest, hold for two seconds, lower, and repeat on the other side. This is the simplest way to isolate hip flexion without stressing your back.
- Active straight leg raise: Lie flat on your back, one leg bent with foot on the floor. Lift the straight leg to about 60 degrees, pause, and lower slowly. This produced the highest iliopsoas activation in EMG research.
- Standing knee drive: Stand on one leg and drive the opposite knee upward toward your chest. Add a resistance band looped around the foot or ankle to increase the challenge.
- Hanging knee raise: Hang from a pull-up bar and bring your knees toward your chest. This loads the hip flexors through a large range of motion under the resistance of your leg weight.
- Cable or band hip flexion: Attach a cable or band around your ankle and drive your knee forward against resistance. This allows precise control of the load and is one of the easiest exercises to progressively overload.
How to Structure Your Training
A protocol from UCSF’s Orthopaedic Institute recommends training hip strengthening exercises three times per week, performing 3 sets of 10 to 15 repetitions per exercise. This is a solid starting framework, especially if you’re coming back from an injury or building a baseline. For general strength, staying in the 10 to 15 rep range with controlled tempo works well.
If your goal is maximal strength rather than endurance, you can shift toward heavier resistance with fewer reps (5 to 8 per set) once you’ve built a foundation. The key principle is progressive overload: your hip flexors adapt to a given resistance quickly, so you need to increase the load, add reps, or slow down the movement over time to keep making gains. A resistance band is the simplest way to start adding load. Cable machines offer the smoothest progression because you can increase weight in small increments.
Rest at least one day between hip flexor sessions. These muscles recover relatively quickly, but training them every day doesn’t allow for the tissue repair that drives strength gains.
Common Mistakes to Avoid
The most frequent error during hip flexor exercises is letting your lower back arch excessively. When the hip flexors fatigue, your pelvis tilts forward and your lumbar spine hyperextends to compensate. This turns a hip exercise into a back strain. During any supine hip flexor exercise, press your lower back into the floor. If your back starts lifting off the ground, the weight or range of motion is too much.
Another common compensation is the knees collapsing inward during standing exercises. Several hip flexor muscles also pull the leg inward, and when they’re overloaded, they drag the knee toward the midline. Keep your knee tracking directly over your foot during standing knee drives and marching variations.
Finally, many people confuse hip flexor tightness with hip flexor strength. Stretching tight hip flexors is not the same as strengthening them, and doing one without the other leaves the problem half-solved. If your hip flexors feel “tight” but you’ve never trained them with resistance, weakness is likely part of the picture.
Testing Your Hip Flexor Strength
A simple self-check: sit on the edge of a chair and try to lift your thigh off the seat while keeping your back straight. If you can hold each leg up for 15 to 20 seconds without your torso leaning back or your lower back arching, your hip flexors have at least a basic level of strength. If one side gives out faster than the other, you have an asymmetry worth addressing.
Clinicians use the Thomas test to assess the hip flexors, but it’s primarily a tightness test rather than a strength test. It distinguishes between muscles that are too short (passive insufficiency) and muscles that are too weak to generate force in a shortened position (active insufficiency). Both conditions limit range of motion at the hip, but they require different interventions. Tightness needs stretching and mobility work. Weakness needs progressive resistance training. Many people have both.
Research on hip strength across age groups shows that older adults produce less accurate force at the hip compared to younger adults, even when overall strength levels are similar. This means that hip flexor training isn’t just about getting stronger. It’s also about improving your ability to control and coordinate force, which matters for balance and fall prevention as you age.