Where Are Your Groin Muscles and What Do They Do?

Your groin muscles sit along the inner thigh, forming a fan-shaped group that runs from the pelvis down toward the knee. Collectively called the hip adductors, they include five main muscles: the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus. Their most obvious job is pulling your leg inward toward the midline of your body, but recent research shows that role only scratches the surface of what they actually do, especially during walking, running, and maintaining balance as you age.

Where Exactly They Are

The groin muscles occupy the medial compartment of the thigh, which is the area along the inside of your upper leg between the front of your thigh (the quadriceps territory) and the back (where the hamstrings live). They originate from different points on the pubic bone and the lower part of the pelvis, and they fan outward and downward, attaching at various points along the femur (your thighbone) and, in one case, all the way down to the shin.

The pectineus is the most forward of the group, sitting high up near the crease of the hip. Just behind and below it is the adductor brevis, a short, triangular muscle. The adductor longus lies superficially on the inner thigh and is the one you can most easily feel when you squeeze your legs together. The adductor magnus is the largest of all, a thick, powerful muscle that stretches from the pelvis down to just above the inside of the knee. And the gracilis is the thinnest and longest, running as a strap-like muscle from the pubic bone all the way past the knee to attach on the inner shin bone. These muscles are primarily innervated by the obturator nerve, which branches into anterior and posterior divisions that supply different muscles in the group.

Because these muscles span from the pelvis to different points along the thigh and lower leg, they cross the hip joint and, in the case of the gracilis, also the knee joint. That multi-joint arrangement is part of what makes them both versatile and vulnerable.

More Than Just Squeezing Your Legs Together

The word “adductor” means a muscle that pulls a limb toward the body’s center line, and that is how these muscles are typically described in anatomy classes. Squeeze a ball between your knees, and your adductors are doing the work. But labeling them purely as adductors sells them short, particularly the adductor magnus.

A 2025 study found that the adductor magnus has a torque-generating capacity for hip extension that is more than twice as great as its capacity for adduction. The researchers concluded that this muscle is architecturally designed to act as a major hip extensor, meaning it powerfully drives your thigh backward, the very motion that propels you forward when walking or running.² An earlier study reached a similar conclusion, advocating that the adductor magnus should be recognized as a hip extensor in clinical testing and exercise programming.³

This matters because it changes how you think about strengthening and rehabilitating the inner thigh. If the adductor magnus is really pulling its weight as a hip extensor, then exercises like lunges and step-ups are training your groin muscles too, not just your glutes and hamstrings. And if the adductor magnus gets weak or injured, you may notice it not as inner-thigh pain during side-to-side movements, but as a loss of power pushing off while walking or sprinting.

The gracilis, meanwhile, crosses both the hip and the knee, which gives it a role in knee flexion as well as hip adduction. Intraoperative measurements have shown that the gracilis can produce force across a wide range of knee positions, from full extension to about 120 degrees of flexion.⁴ Its dual-joint nature is also why surgeons sometimes harvest the gracilis tendon for use in knee ligament reconstructions: it is expendable enough that the other adductors can compensate, yet strong enough that its tendon makes a useful graft.

What These Muscles Do During Sports and Cutting Movements

Your groin muscles are rarely working in isolation. During most athletic movements, they coordinate with the hip abductors (the muscles on the outside of the hip, mainly the gluteus medius) to stabilize the pelvis. Think of the inner and outer thigh muscles as a tug-of-war pair: the adductors pull the leg in, the abductors push it out, and together they keep you from wobbling side to side.

This partnership gets tested during cutting maneuvers, the quick lateral direction changes common in soccer, football, basketball, and similar field sports. Research using muscle-activity sensors during 45-degree run-to-cut movements found that the adductor longus is heavily active during the entire stance phase of the cutting leg.⁵ A separate study comparing cutting maneuvers to inside passing in soccer found that both the adductor longus and the gracilis showed higher peak activity during cutting than during passing, with the adductor longus reaching maximum activity at roughly the midpoint of ground contact.⁶

Kicking is another high-demand task for the groin. During a maximal-effort soccer kick, the adductor longus is stretched rapidly as the leg swings back, reaching its highest rate of stretch at around 40% of the swing phase and its greatest overall length at around 65% of the swing.⁷ That quick stretch under high force is exactly the scenario that sets the stage for a strain, which is why kicking and twisting sports are the most common contexts for groin injuries.

Why Groin Strains Happen and Who Gets Them

Groin pain in athletes accounts for roughly 5% to 23% of all sports injuries, depending on the sport and definition used, and is most common in soccer players.⁸ The adductor longus is the usual suspect. One reason is structural: its tendon where it attaches to the pubic bone has a relatively small cross-sectional area, and much of its origin is formed by muscle fibers attaching directly to bone rather than through a thick, robust tendon.⁹ In practical terms, a lot of force is concentrated on a small connection point, making it the weak link in the chain.

Another factor is the balance between the adductors and abductors. In athletes with chronic groin pain, the ratio of gluteus medius (abductor) to adductor longus activity is significantly reduced, by roughly 20 to 40% compared to healthy athletes, depending on the phase of movement. The difference comes mainly from decreased abductor activation rather than overactive adductors.¹⁰ When the abductors are not doing their share, the adductors pick up the slack in stabilizing the pelvis, and the added load can push an already strained muscle past its limits.

This imbalance connects to the broader problem of pelvic stability. A systematic review of sports hernias, a related form of chronic groin pain involving the inguinal wall, identified poorly balanced hip adductor and abdominal muscle activation as a likely causative factor. The repetitive shear forces applied through the pelvic attachments of these muscles can weaken the posterior wall of the inguinal canal over time.¹¹ In other words, groin problems are rarely just about the groin muscles in isolation; they reflect how the whole hip-pelvis-core system is coordinating.

Sex Differences in Groin Biomechanics

Men and women do not move their hips identically, and those differences show up in how groin pain presents. A study comparing men and women who already had hip-related groin pain found that during walking, men used less hip flexion and internal rotation during stance than women did. Men also displayed lower hip adduction angles and lower knee flexion angles. During a single-leg drop jump, men landed with less hip flexion in early stance and generated greater moments at the knee and ankle.¹²

What this suggests is that men and women may compensate for groin pain in different ways, using different joint strategies to offload the painful area. For clinicians and trainers, the takeaway is that a one-size-fits-all approach to groin rehabilitation probably misses the mark. Women with groin pain tend to use more hip motion during functional tasks, while men tend to stiffen the hip and shift demand elsewhere. A targeted rehab program should account for which compensation pattern is actually happening.

Strengthening the Groin and Preventing Injuries

The most studied exercise for groin injury prevention is the Copenhagen Adduction Exercise. You perform it by lying on your side with a partner holding your top leg at the ankle or knee while you lift and lower your body using your adductors. It is essentially a side plank powered by the groin instead of the shoulder and core.

A systematic review found that the Copenhagen exercise consistently improves eccentric hip adduction strength, hip range of motion, and dynamic balance while reducing groin-related symptoms. Higher training volumes and progressive overload yield better results.¹³ Another systematic review confirmed that every study measuring eccentric hip adduction strength found a significant increase in groups using the exercise, along with improvements in the ratio of adduction to abduction strength.¹⁴

A randomized controlled trial in male soccer players went further, comparing the standard FIFA 11+ warm-up program with a modified version that added the Copenhagen exercise. The group doing the Copenhagen exercise gained about 9% more eccentric hip adduction strength than the standard group, while the control group showed essentially no change at all.¹⁵ The fact that the standard program produced no adduction strength gain while the modified version did suggests that popular warm-up routines often neglect the groin entirely.

Beyond the Copenhagen exercise, rehabilitation for groin strains typically involves a progression from isometric squeezes (pressing the knees together against a ball) to dynamic movements like side lunges and resisted adduction with bands, and eventually back to sport-specific drills. The key principle is that eccentric strength, the ability to control the muscle while it is being lengthened, is what protects against the kind of rapid-stretch injuries that happen during kicking and cutting.

Compression Shorts and Adductor Demand

One interesting finding from the biomechanics literature involves directional compression shorts, garments engineered to provide targeted resistance around the hip. When healthy athletes performed unanticipated cutting maneuvers in directional compression shorts, their stance-leg adductor longus activity was significantly lower across all phases of ground contact compared to wearing standard non-directional compression shorts.⁵ The implication is that the garment provides some external support that partially unloads the adductors during high-demand movements. For athletes recovering from a groin strain who are approaching return to play, this could reduce the demand on healing tissue during the transition back to full activity. It is not a replacement for strengthening, but it might help bridge the gap.

How Groin Strength Changes With Age

Groin injuries get the spotlight in sports medicine, but the groin muscles matter just as much for older adults trying to stay on their feet. Hip adductor and abductor strength together control side-to-side stability, and when that strength declines, fall risk rises.

A study measuring hip torques in younger versus older women found that isometric adduction peak torque was about 24% lower in older women, while abduction was about 34% lower. When tested at faster, more dynamic speeds, the declines were steeper: adduction strength dropped by roughly 56%, and abduction by about 44%.¹⁶ The dynamic strength losses are the more worrying numbers, because catching yourself from a stumble or regaining balance on an uneven surface requires generating force quickly, not just generating force in a controlled, slow setting.

Research on age-related strength loss across different muscle groups has raised the concern that stabilizer muscles, including the adductors and abductors, may lose strength faster than the primary movers like the quadriceps. The logic is straightforward: as people age and become less active, the movements they drop first tend to be the lateral and rotational ones. You still walk forward, climb stairs, and stand up from chairs (all quad-dominant tasks), but you rarely perform side-stepping, skating motions, or any other activities that challenge the adductors and abductors. The muscles that are used less frequently atrophy faster.¹⁷

For older adults, this means that including some form of lateral leg exercise, whether it is side-lying leg lifts, banded side-steps, or even a modified version of the Copenhagen exercise scaled to fitness level, could help maintain the very muscle groups that keep you from falling sideways. Standard strength training programs tend to focus on squats, leg presses, and hamstring curls, all of which move in the forward-backward plane. The adductors and abductors need their own attention.

The Gracilis as a Surgical Resource

The gracilis occupies an unusual niche in surgery. Because it is long, relatively thin, and not critical to daily function when the other adductors are intact, its tendon is one of the most commonly harvested tissues for reconstructive procedures. It is frequently used as a graft in ACL (anterior cruciate ligament) reconstruction, often paired with the semitendinosus tendon. It also sees use in procedures to reconstruct other ligaments and even in reconstructive surgeries outside the knee, such as procedures to restore hand grip or facial movement.

Intraoperative force testing in both healthy and spastic gracilis muscles has confirmed that the muscle operates across a wide functional range, but individual variation is considerable. In some people, peak force occurs at high knee flexion angles; in others, it occurs much earlier. Spastic gracilis muscles, studied in patients undergoing surgery for conditions like cerebral palsy, produced forces across the full tested range but with highly variable peak values.¹⁸ The clinical relevance is that surgeons can harvest the gracilis tendon with reasonable confidence that the patient will not lose meaningful inner-thigh function, though individual anatomy always warrants careful evaluation.

When Groin Pain Is Not a Muscle Problem

Not all groin pain comes from the adductor muscles. The groin region is anatomically crowded, and several structures share the neighborhood. Sports hernias, also called athletic pubalgia, involve disruption of the soft tissues around the inguinal canal, the passage through the abdominal wall where blood vessels and nerves travel to and from the leg. Symptoms overlap heavily with adductor strains: pain in the lower abdomen or inner thigh, especially with exertion. A comprehensive review noted that sports hernias remain a significant diagnostic challenge, often requiring a multidisciplinary approach combining clinical examination, imaging, and sometimes diagnostic injections to distinguish them from muscle strains.¹⁹

Hip joint problems can also masquerade as groin pain. Labral tears, femoroacetabular impingement (where the ball and socket of the hip joint do not fit together smoothly), and early hip arthritis can all produce pain that the brain registers as coming from the groin. The pain referral pattern makes anatomical sense: the hip joint sits deep within the same territory as the adductor origins, and the obturator nerve that supplies most of the groin muscles also has branches serving the hip joint capsule. If you have persistent groin pain that does not improve with adductor-focused rehab, the source might be the joint itself rather than the muscles around it.

Nerve entrapment is another less common culprit. The obturator nerve can become compressed or irritated where it passes through a narrow channel in the pelvis, producing pain, weakness, or numbness in the inner thigh. And in non-athletes, groin pain may stem from inguinal hernias (the traditional kind, where abdominal contents push through the inguinal canal), kidney stones, or referred pain from the lumbar spine. The groin is a crossroads, and the challenge with pain in the region is that the symptom is rarely specific enough on its own to pin down the cause without further investigation.