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Hamstring flexibility


Being flexible is the same as being limber. It is important for your child’s muscles to be flexible, because tight muscles hurt, they are more easily injured, and they can cause difficulty with walking. Children treated for cancer often have tightness in the big group of muscles on the back of the thigh. These muscles are called the hamstrings. The hamstrings go all the way from the back of the knee up to the buttocks. They are the muscles that help bend the knee and straighten the hip. These muscles are very likely to get tight when children are inactive, particularly if they spend a lot of time sitting or in bed.


Here is an example of what may happen when the hamstrings are tight.

When we stand still, our ears, shoulders, hips, knees, and ankles should all “stack up” on top of each other. But when the hamstrings are tight, they pull on the tailbone and tuck it up under the spine. This flattens the lower back and bends the knees. Before you know it, your child has pain in the lower back and finds some things harder to do.

How do I know my child's hamstrings are getting tight?

If children cannot sit on the floor with their legs straight in front of them without bending their knees or leaning back, we recommend that they do stretching exercises at least 3 times a week.


How do I help my child with hamstring stretches?

There are many ways to stretch. The best stretch is the one your child will do! Your therapist will help you choose the right exercise for your child. For stretches to work, they need to be slow and prolonged. If the exercise is done correctly, your child will feel a pull on the back of the thigh and behind the knee, but not pain.

If you have questions about hamstring flexibility, call Rehabilitation Services at 595-3621. If you are inside the hospital, dial 3621. If you are outside the Memphis area, call toll-free 1-866-2ST-JUDE (1-866-278-5833), extension 3621.


This document is not intended to take the place of the care and attention of your personal physician or other professional medical services. Our aim is to promote active participation in your care and treatment by providing information and education. Questions about individual health concerns or specific treatment options should be discussed with your physician.

St. Jude complies with health care-related federal civil rights laws and does not discriminate on the basis of race, color, national origin, age, disability, or sex.

ATTENTION: If you speak another language, assistance services, free of charge, are available to you. Call 1-866-278-5833 (TTY: 1-901-595-1040).

ATENCIÓN: si habla español, tiene a su disposición servicios gratuitos de asistencia lingüística. Llame al 1-866-278-5833 (TTY: 1-901-595-1040).

تنبيه: إذا كنت تتحدث باللغة العربية فيمكنك الاستعانة بخدمات المساعدة اللغوية المتوفرة لك مجانا. .يرجى الاتصال بالرقم. 5833-278-866-1  (الهاتف النصي: 1040-595-901-1).