Do you have a squatty potty. It helps. But optimally we should be in a full squat when we do our business. When you get ready to go, focus on long slow breathes. Don't strain but do try to expand your belly, straighten your back and pinch your shoulder blades together. sorry if this sounds woo woo, but it helps with the peristalsis. If you have lower back pain try some magnesium lotion. I have also heard people recommend soaking the feet in Epsom salts. Practice squatting down like you would do it in the wild. That is how our body is designed to release this crap...not sitting on a chair. Dr Sean O'Mara has a video about duecing like a rockstar. It is not too far down his timeline.