Several times a month, my 9-year-old complains of uncomfortable leg aches (but not pain) at bedtime. I’ve been telling her they’re “growing pains,” but it makes me wonder — what exactly are growing pains? Are there any signs I should look for to ensure it’s nothing more serious? How long do these go on for?

We can all remember our parents telling us, “Oh, those are growing pains,” and many of us have said the same to our own children any number of times.

But I am here to tell you that these pains have nothing to do with growth, per se. There is no actual pain that goes along with growing. More often than not, these pains children often feel — for what seems like no reason — are really pains related to muscle aches due to activity. Kids are active. They can spend a day running around with no regard to the effect it is having on their bodies. Then, hours later the activity stops, their bodies rest, and aches and pains set in. Just as adults get muscle aches, pains, and soreness from a strenuous workout or increased activity — kids do, too.

What many refer to as “growing pains” are more about movement than growth. Even during a growth spurt, children aren’t growing fast enough to cause pain. But these aches and pains come, and for children, they are unexpected. In many cases, these aches and pains come at the end of the day — and in just as many instances, they are gone by the morning. However, we never want to ignore any child if they are complaining of pain.

A simple rule to follow is RICE: Rest, Ice, Compression, and Elevation. If it seems necessary, you can give your children ibuprofen or Tylenol to help them, but it may not be needed. I always advise following the RICE rule first. That being said, if the pain doesn’t get better with time — or if it worsens — you should contact your child’s pediatrician.

Additionally, if the area is red or swelling, you feel any lumps, they are limping from the pain, or are increasingly unable to participate in regular activities, also consult their pediatrician.

You know your child best, if their pain or discomfort level seems abnormal or concerning, always reach out to their doctor and have them checked.

Mary Brown, M.D., is a pediatrician at Floating Hospital for Children at Tufts Medical Center and an assistant professor at Tufts University School of Medicine.