What Do the Adductors Work? Their Function Explained

The hip adductors pull your thigh toward the midline of your body, but that textbook definition undersells them. This group of muscles on the inner thigh also contributes to hip extension, hip flexion, internal rotation, and pelvic stability depending on which adductor fires and what position your hip is in. Recent research has reframed one of the largest members, the adductor magnus, as primarily a hip extensor rather than a simple adductor, which upends how many people think about inner-thigh muscles.

The Five Muscles and What Each One Actually Does

The hip adductor group consists of five muscles stacked along the inner thigh: the adductor magnus, adductor longus, adductor brevis, pectineus, and gracilis. They all attach somewhere along the pubic bone and fan downward to various points on the femur (except the gracilis, which crosses the knee and attaches to the tibia). Because they originate and insert at different angles, each muscle has a slightly different secondary role beyond pulling the leg inward.

The adductor magnus is the largest of the group and the one that has gotten the most scientific attention in recent years. A 2025 study in the Journal of Applied Physiology concluded that the adductor magnus is designed to act primarily as a hip extensor rather than an adductor in living young adults, based on its moment arm and muscle architecture.¹ That finding is consistent with earlier work showing that the adductor magnus should be classified alongside the gluteus maximus and hamstrings during hip extension exercises.² In practical terms, every time you stand up from a chair, climb stairs, or drive your leg backward while sprinting, the adductor magnus is contributing as an extensor, not just squeezing your knees together.

The pectineus, adductor longus, and adductor brevis sit higher and more forward. MRI-based evaluation shows these three muscles are significantly more active during internal rotation of the hip than during external rotation, suggesting they help rotate the thigh inward as a secondary function.³ The pectineus also assists hip flexion because of its high attachment point. The gracilis, the thinnest of the group, is the only one that crosses both the hip and the knee, so it helps with knee flexion and internal rotation of the lower leg in addition to hip adduction.

Why the Adductor Magnus Deserves Its Own Conversation

The adductor magnus has two distinct portions: a pubic (or adductor) portion and an ischial (or hamstring-like) portion. The ischial portion originates from the same bony landmark as the hamstrings, the ischial tuberosity, and its fibers run nearly vertically down to a bump on the inner femur near the knee. This anatomy gives it a powerful line of pull for hip extension, especially when the hip is flexed.

Biomechanical studies measuring moment arm lengths bear this out. When the hip is in its neutral anatomical position, the adductor magnus has a relatively short extension moment arm compared to the gluteus maximus and hamstrings. But as the hip flexes further, the adductor magnus’s moment arm for extension increases substantially, peaking around 75 degrees of flexion before decreasing again.⁴ This means the adductor magnus becomes a more potent hip extensor as you squat deeper or lean forward, exactly the positions where you need the most help driving back upright.

For anyone who trains with barbells or does explosive sports, this has real implications. The adductor magnus is not a minor helper during squats and deadlifts. It is a genuine driver of the movement, especially in the bottom portion of the range. Thinking of the inner thigh as purely an “adduction” area misses a significant source of hip extension strength.

How Squats and Stance Width Change Adductor Demand

The width of your squat stance meaningfully shifts which muscles work hardest. Research comparing narrow, medium, and wide squat stances found that a wider stance increased the hip extensor moment demand compared to narrower stances.⁵ The wider you go, the more the adductors are stretched at the bottom of the squat, which places them in a position to contribute more forcefully to hip extension on the way up. Wide stances also increased the lateral rotator demand at the hip, reflecting the complex interplay between adduction, extension, and rotation as stance widens.

Squat depth matters too. A training study comparing full squats (where the thigh drops well below parallel) to half squats found that full squats produced significantly greater volume increases in both the adductor muscles and the gluteus maximus. The adductors grew by roughly 6% in the full-squat group compared to about 3% in the half-squat group over the training period.⁶ If your goal is to develop your adductors through compound movements, squatting deeper and wider seems to deliver a stronger stimulus than shallow or narrow squats.

The Adductors During Walking, Running, and Changing Direction

Walking and running demand far more from the adductors than most people realize. Every step involves a brief single-leg stance phase where the pelvis wants to drop on the unsupported side. The hip abductors (gluteus medius and minimus) on the stance leg resist that drop, but the adductors on the same side co-contract with them to stabilize the pelvis and control the leg during the swing phase. Electromyography research across a range of walking and running speeds and inclines found that the hip adductors, gluteus maximus, and hamstrings were among the muscles most affected by changes in speed and grade.⁷ People with a broader pelvis showed reduced activity in the hip adductors and hamstrings during walking, likely because the wider bone geometry gives those muscles a better mechanical advantage so they don’t have to work as hard.

In sports that involve cutting and direction changes, the adductors take on an even bigger role. During a run-to-cut maneuver, the stance leg’s adductors fire hard to control the body’s momentum as it shifts laterally. One study found that wearing directional compression shorts was associated with reduced stance-limb hip adductor activity during cutting, suggesting the garments partially offloaded the adductors, which could be useful for athletes returning from groin injuries.⁸

Kicking and the Adductor’s Vulnerability

Soccer and similar kicking sports place enormous demands on the adductor longus specifically. During a maximal-effort soccer kick, the adductor longus is stretched rapidly as the kicking leg swings back into hip extension and abduction. The maximum rate of stretch and peak hip extension occur near 40% of the swing phase, while the muscle is actively contracting.⁹ That combination of lengthening under load is exactly the scenario that produces muscle strains, and it explains why adductor injuries are so common among soccer players.

The adductors don’t just serve the kicking leg. In the supporting leg during a kick, surface electromyography showed that both the adductor magnus and adductor longus had significantly increased activity as ball speed rose.¹⁰ The plant leg has to stabilize the entire pelvis against the rotational forces generated by the kicking leg, and the adductors are central to that job. Harder kicks mean greater stabilization demand, which means more adductor work on both sides of the body.

The mechanical stress goes beyond muscle fibers. The adductor longus tendon shares a common attachment point (an aponeurotic plate) with the rectus abdominis near the pubic bone. Repetitive kicking, hockey slap shots, and other motions that combine hip hyperextension with trunk twisting can strain or tear this shared attachment, leading to a condition sometimes called athletic pubalgia or “sports hernia.”¹¹

Groin Injury Risk and Adductor Strength

Groin injuries are among the most common non-contact injuries in field and ice sports, and weak adductors are frequently blamed. The picture is a bit more nuanced than “weak adductors equal groin strains,” though. A prospective study of male soccer players found that an imbalance in the isometric hip adductor-to-abductor strength ratio in the non-dominant limb, combined with a history of previous injury, were significant predictors of future groin injury.¹² In hockey and soccer, measuring the adductor-to-abductor ratio has been advocated as a useful preseason screening tool to identify athletes who might benefit from targeted strengthening.¹³

However, a systematic review and meta-analysis published in the British Journal of Sports Medicine found that the effects of baseline adductor strength and adductor-to-abductor ratio on future groin pain were only trivial in magnitude across pooled studies.¹⁴ The takeaway: strength ratios may flag higher-risk individuals within certain sports, but adductor weakness alone is not a reliable crystal ball for who will get hurt. Previous injury history remains one of the strongest predictors, and the interaction between strength, fatigue, movement patterns, and training load is complex.

Training the Adductors for Injury Prevention

The Copenhagen adductor exercise has become one of the most studied and recommended exercises for adductor strengthening, particularly in team sports. In this exercise, you lie on your side with the top foot on a bench and the bottom leg hanging free, then lift your body by squeezing the top leg against the bench. It demands high activation from both the adductor longus and adductor magnus, producing substantially greater muscle activity than simpler alternatives like the adductor slide.¹⁵

In a cluster-randomized trial of semi-professional soccer teams, an adductor strengthening program built around the Copenhagen exercise produced a 41% lower risk of reporting groin problems during the season compared to teams that trained as usual.¹⁶ Broader systematic review evidence from randomized controlled trials supports reductions of roughly 30 to 41% in groin injury incidence among male soccer and high school athletes using this type of program compared to standard training.¹⁷ Given how simple and equipment-free the exercise is, its adoption in team warm-ups has grown rapidly. For individuals who are not athletes, any form of progressive adductor strengthening (side-lying leg lifts, cable adduction, sumo squats) can help maintain the strength balance between the inner and outer thigh, which matters for reasons beyond groin injury.

Adductors, Knee Stability, and ACL Injury Risk

The adductors influence what happens at the knee, not just at the hip. During single-leg landings, the ratio of adductor longus activity to gluteus medius activity was independently associated with the knee valgus moment, which is the inward-collapsing force on the knee that is linked to ACL tears.¹⁸ When the adductors overpower the abductors during landing, the thigh tends to rotate inward and the knee drifts medially, placing more stress on the ACL.

A separate study looking at isometric hip strength ratios during jump-landing tasks confirmed that a higher adduction-to-abduction strength ratio was linked to increased hip internal rotation at both initial contact and during the landing’s braking phase.¹⁹ This does not mean strong adductors are bad for your knees. It means the balance between adductor and abductor strength matters. If your adductors are strong relative to your glute medius, the resulting imbalance can feed into the dynamic knee valgus pattern. The practical lesson: training the adductors in isolation without also training the hip abductors can create its own problems. Balanced hip strengthening is the goal.

Balance and Falls in Older Adults

The adductors play a surprisingly direct role in preventing falls as people age. Recovering from a sideways stumble requires a rapid lateral weight shift, and the hip adductors and abductors drive that shift. Age-related declines in the rate of force development and power production in these muscles impair the ability to execute a quick protective step to the side.

An eight-week study of older adults compared low-dose hip abductor-adductor power training (fast, explosive contractions) to traditional strength training (slower, heavier loads). The power training group showed greater improvements in both maximal neuromuscular performance and lateral balance recovery than the strength group.²⁰ The finding suggests that for fall prevention, it’s not just about making the adductors and abductors stronger in the traditional sense. Training them to produce force quickly, which is what a stumble actually demands, may be more effective.

Sex Differences in Adductor Anatomy

Men and women differ in pelvic width, femoral neck angle, and other skeletal dimensions that affect how the adductor muscles pull on the femur. Modeling research has found that global anthropometric measurements like height and body mass are poor predictors of adductor moment arms and show significant sex-specific differences, meaning you cannot simply scale a male model down to estimate female adductor mechanics. Regional and local bone features (the shape of the femoral head, the angle of the neck, the width of the pelvis) are much better predictors of moment arm variation and inherently capture many of the differences between sexes without needing separate correction factors.²¹ This matters mostly for biomechanical modeling and surgical planning, but it underlines a broader point: the adductors do not function identically in every body. Pelvic geometry affects their leverage, and that geometry differs not just between sexes but between individuals.

How Human Adductors Evolved

Compared to other primates, humans have undergone dramatic restructuring of the hip musculature to accommodate upright walking and running. The gluteus maximus expanded enormously, the gluteus medius and minimus shifted from extensors to abductors, and the hamstrings and quadriceps changed their relative proportions. The adductors, by contrast, changed relatively little in their functional anatomy during this evolutionary transition.²² They retained their role as thigh adductors and secondary hip flexors and extensors, much as they functioned in the common ancestor of apes and humans. This evolutionary conservatism is actually a testament to how fundamental the adductors are: the demands of bipedal locomotion reshuffled nearly every other hip muscle group, but the adductors were already versatile enough to work in the new configuration without major redesign.