Strengthen to lengthen
It seems paradoxical that if your hamstrings are tight, you should strengthen them. However, hamstrings are healthiest when all of their fibers are able to fully lengthen and contract, which is what prevents muscle tears and promotes optimal muscle health. The following exercise is like medicine for both hypermobile and restricted hamstrings. It’s a concentric exercise (read: it shortens the hamstrings). If you dislike this move as much as I do, take it as a sign that you’ve got some hamstringstrengthening work to do.
THE MOVE: HAMSTRING SLIDES STEP ONE
Place a yoga blanket on a slippery surface, like a hardwood or tile floor. Lie down to rest your bottom, torso, and head on the blanket with your legs outstretched in front of you, hips parallel to each other.
Drive your heels into the floor, and pull your bottom toward your heels by exclusively using your hamstrings. When you’re halfway there, stop and make sure your knees are pointing to the sky and still parallel to one another.
Complete the move by pulling your heels all the way to your bottom, then straighten your legs to return to the starting position. Repeat until you feel tired.