Bending the knees in all the forward bends in order to relieve the tension so that it is completely pain free usually helps.
May 02, 2010 Rating
Forward Bends Cause the Strain by: Lis
It is the forward bends that cause the strain. Because the tendons that connect the hamstring to the sit bone is damaged, the stretch tends to go right there, to the weakest part.
May 01, 2010 Rating
Rest for a Week by: Ashtangi
Hard to really say without more info on what postures seem to be causing the stress to the body.
My advice would be rest for a week.... no practice.
Then slowly build the practice back up, posture by posture in a Mysore class if possible.
Practice without feeling any strain during the practice.