You’ll want to be careful with this stretch. See a medical doctor or a physical therapist if you are having low back pain that goes into your buttock and/or down the leg during this activity.
If you’re just having some local low back discomfort, you can place a pillow, blanket, or towels under your abdomen. This can help put your lumbar spine in a more neutral position and take the pressure off the area. Sometimes it’s necessary to start with two pillows. Slowly remove one pillow at a time as your symptoms improve.
Decrease the thickness of the pillows or support when you are able to hold each stretch for 30 seconds without trouble or pain. Stretches should be done slowly with proper breathing. Never bounce or “push through the pain.”