The following exercises are not recommended. Avoid bending over to stretch the hamstrings. This exercise contracts the hamstring muscles.
Little flexibility is gained when a muscle is contracting.
Forward flexion past 70 stresses the lower back. Avoid any kind of double leg lift. Hip flexor and lower back muscles perform much of the work in a double leg lift. Avoid flexion and rotation exercises. Flexion and rotation exercises put the back in the most vulnerable position for injury.