This is not medical advice.
I’m not a huge fan of hamstring stretches, but if you are going to do them, this posture may help decrease low back pain.
It is curious that we have a test for low back problems called the “straight leg raise test.” Basically we stretch your hamstrings, and sciatic nerve at the same time, and if it hurts, some of us give you more of the same (?)
Touching our toes has always been an arbitrary measure of flexibility. We have these things called knees. They bend, so that we can reach the ground. I’ve never seen indigenous people stretching their hamstrings, or touching their toes before hunting.
There are of course people who need to be very flexible, and can handle it, like gymnasts, wrestlers and acrobats. However, in all those cases, the athletes are very slim, and have amazing core musculature supporting their spine.
Isn’t it curious that the hamstrings are simultaneously the most stretched and strained/injured muscles? And the calf/Achilles are a close second?
That’s not to say that we never need to stretch. It’s just that there should be a context for stretching.