A groin injury is damage to one or more of the five muscles on the inner thigh that pull your leg toward the center of your body. These muscles, called the adductors, also help with balance and stabilization during movement. Groin injuries range from a mild stretch that heals in days to a complete muscle tear requiring months of recovery, and they account for 2 to 5 percent of all sports injuries.
The Muscles Involved
Your groin is made up of five muscles: the adductor longus, adductor brevis, adductor magnus, gracilis, and pectineus. They fan out from your pelvis down the inside of your thigh, and their job is straightforward. Every time you squeeze your legs together, pivot, or shift your weight sideways, these muscles are doing the work.
The adductor longus is the most commonly injured of the group. It sits near the surface and connects to the pelvis at a narrow tendon, which makes it vulnerable during sudden changes in direction. The tendons that anchor these muscles to the pelvis are often the weak link, especially in movements that combine twisting with force, like a hard cut in soccer or a quick lateral push in hockey. The abdominal muscles that attach to the pelvis, particularly the internal oblique, can also be strained in the same motion.
How Groin Injuries Are Graded
Groin strains are classified by severity into three grades:
- Grade 1: A mild stretch or tear of just a few muscle fibers. The area is tender and painful, but the muscle keeps its normal strength. You can usually walk and do light activity.
- Grade 2: A partial tear involving more of the muscle. Pain is more noticeable, strength is reduced, and movements like side-stepping or climbing stairs become difficult.
- Grade 3: A complete tear or rupture of the muscle or tendon. This often produces a sharp, sudden pain and significant loss of function. Bruising and swelling typically follow.
What It Feels Like
Most groin injuries happen in a single moment: a quick twist, a sudden sprint, or an explosive change of direction. You may feel a pull, a pop, or a sharp sting along the inner thigh. In mild cases, the pain only shows up when you try to squeeze your legs together or accelerate. In more severe tears, even walking can be uncomfortable.
Groin pain can also develop gradually. Repetitive stress from running, skating, or kicking can create low-grade damage that worsens over time. This type of injury often starts as tightness or a dull ache after activity, then progresses to pain during activity if it’s not addressed.
What Else Groin Pain Could Be
Not all groin pain comes from a muscle strain. An inguinal hernia, where fatty tissue or a loop of intestine pushes through a weak spot in the abdominal wall, can cause similar symptoms: a dull ache, burning pain, or heaviness when you stand. The key physical difference is that a hernia typically produces a noticeable lump in the groin area, something you won’t feel with a muscle strain.
You may also hear the term “sports hernia,” which is misleading. It’s not actually a hernia. It’s a strain of the muscles or tendons where the abdominals and adductors meet near the pubic bone. The symptoms overlap significantly with a standard groin strain, and the distinction often requires imaging or a specialist’s evaluation.
An international panel of sports medicine experts established a standardized classification system (known as the Doha agreement) that groups groin pain into categories based on what structure is involved: adductor-related, iliopsoas-related (the deep hip flexor), inguinal-related, pubic-related, or hip joint-related. This framework helps clinicians avoid vague diagnoses and treat the right structure.
Who Is Most at Risk
Having a previous groin injury is the single strongest predictor of getting another one. Research on male soccer players found that a prior hip or groin injury nearly doubled the risk of a new injury. Weakness in the inner thigh muscles is another significant factor: players with lower-than-normal adductor strength were about 70 percent more likely to suffer an adductor-related injury.
Interestingly, having higher-than-normal adductor strength also correlated with increased risk, possibly because stronger muscles generate more force at the tendon attachment points. Bony hip shape, including a common structural variation called cam morphology found in 60 percent of the players studied, did not increase injury risk.
Groin injuries are especially common in sports that demand lateral movement, sudden acceleration, or kicking. Soccer players see the highest rates, with groin injuries making up 5 to 7 percent of all their injuries. Ice hockey, fencing, handball, cross-country skiing, and hurdling also carry elevated risk.
How It’s Diagnosed
Diagnosis starts with a physical exam. A clinician will press along your inner thigh and pubic bone to locate tenderness, then ask you to squeeze your legs together against resistance to see if it reproduces your pain. They may also stretch your adductors to check whether that triggers symptoms. These simple provocation tests, palpation, resistance, and stretch, are reliable enough to guide initial treatment in most cases. Imaging like MRI is typically reserved for injuries that don’t improve as expected or when a complete tear is suspected.
Recovery Timelines
How long recovery takes depends almost entirely on severity. A Grade 1 strain may only need a week or two of rest and gentle stretching before you can return to normal activity. Partial tears (Grade 2) often allow a return to sport within two to three weeks. Complete tears are a different story, typically requiring eight to twelve weeks of rehabilitation.
During recovery, the focus shifts from protecting the injured tissue to progressively loading it. Early on, that means gentle range-of-motion work and avoiding movements that provoke pain. As healing progresses, strengthening exercises gradually increase in intensity until you can tolerate sport-specific movements at full effort.
When Surgery Becomes an Option
Most groin injuries heal without surgery. The threshold for surgical intervention is usually three to six months of physical therapy and medical treatment without meaningful improvement. For athletes with complete tendon tears that pull away from the bone (called avulsions), surgical repair can offer a more reliable path back to competition, with return to play typically taking 10 to 14 weeks after the procedure.
Outcomes from surgery are generally favorable. One study of athletes who underwent surgical release for chronic groin pain reported symptom resolution in 93.3 percent of cases, with a complication rate of just 6.7 percent.
Preventing Groin Injuries
The most studied prevention tool is the Copenhagen adduction exercise, a partner-based movement where you hold your body in a side plank while your partner supports your top leg, and you lift your bottom leg using your inner thigh muscles. Research on its effectiveness in soccer teams has shown injury risk reductions of up to 41 percent, though results vary depending on how consistently teams use it.
In practice, teams typically incorporate one to two sessions per week, performing two to three sets of eight to ten repetitions. Volume and intensity are often reduced before games and adjusted based on individual needs. The exercise is simple enough to do with no equipment beyond a training partner, and it directly targets the adductor strength that research identifies as a key protective factor.