For someone with really tight hamstrings what are the pros and cons of using blocks and higher props such as a chair, versus, bending the knees and having hand on the floor or on blocks in Uttanasana.
To simplify this a bit and perhaps reduce it lower than I’d normally like (down to “just” asana) the physiology of the pose is the lengthening of the hamstrings. As long as you, the student, are working to lift the sitting bones up toward the sky then it doesn’t matter much whether your hands are on a chair or a block.
Obviously when the knees are flexed (bent) then the hamstrings are getting less work (the two attachment are technically moving toward each other rather than away). And so bending the knees is an escape or release for students with overly tense or hypertonic hamstrings.
When you are using a “higher prop” as you say, the spine is not dropping AND it cannot be tractioned by the weight of the head. Further, the aforementioned lift of the sitting bones can allow for the anterior tip of the pelvis. This last action takes the forward bend out of the spine and places it in the hips where it should be.
Both methods can be used to open hypertonic hamstrings. The work is slightly different in each though I’d not particularly call it pro and con.
gordon
Take care of your lower back it is all connected .bending the knees helps
Breathe exhale and hold relax inhale to flat back repeat exhale .
Yoga poses are not pictures in a book ,it is your yoga the most important thing is the breath.
Cheers. Love