It depends, but you should always check with your physician before proceeding with playing football since there is a different degree of inguinal hernias and everyone is going to have a different set of circumstances.
First, it is important to understand that true inguinal hernias come in different forms. There are both direct and indirect types. This classification basically identifies where the hernia is coming from on the inguinal floor. With an indirect hernia, the abdominal contents are pushing through the internal ring of the inguinal floor, following the cord structures in a male patient, or the round ligament in a female patient. With a direct inguinal hernia, the abdominal contents push through the weakened floor musculature at Hasselbach’s triangle. Both of these inguinal hernias are essentially in the same area and can cause similar symptoms and presentation clinically. The more import finding is whether the indirect or direct inguinal hernia is reducible, incarcerated, or strangulated. These three terms are very important to understand and can help one understand why your physician is recommending a certain treatment plan, timeline for surgery, and potentially not allowing participation in sports, including football.
A reducible inguinal hernia is one that will appear when standing or during activities but will fall back into the abdominal cavity with gentile pressure. You are essentially able to push, or “reduce”, the hernia back into the abdomen. If this hernia is small enough, then it is likely ok to continue playing football. If the hernia is larger, then the discomfort will likely be more intense and there is a potential for the intestines or fat to become stuck, or “incarcerated’ in the inguinal canal. This will often present as a bulge in the groin crease that will not go away and can be come tender. While this is often not an emergent issue, surgery is likely required and should be done sooner than later to prevent worsening symptoms. Finally, in the most severe cases, if the hernia become strangulated, the blood supply to the intestines and the passage of the digested food become blocked, causing severe pain. This is an emergency and surgery need to be done right away to reduce the hernia and unkink the intestines.
In the case of a sports hernia, it is usually acceptable to continue playing football, but once again this depends on the clinical findings, pain, and radiographic findings. Since a sports hernia is not a true hernia, there is no risk for the intestines to strangulate, leading to an emergency surgery. However, the terms sports hernia often gets thrown around as any pain in the inguinal area, abdominal wall, adductor insertion on the upper inner thigh, among other things. If it is a classic sports hernia in the inguinal crease on the lower abdomen, most athletes can continue to play depending on the severity of pain. For my athletes that have mild to moderate pain, I will often let them continue to play until the end of the season if they can tolerate it. Then we do the surgery after the season. However, for the athletes who have more severe symptoms, or cannot play at a competitive level, then I will recommend surgery.
Obviously, there is a bit of variability with the recommendations since no two people are exactly alike. And it is always recommended that you be evaluated by your physician before continuing to play football if there is a groin problem.