Done properly, lifting weights doesn’t usually hurt your back. In fact, it may help relieve chronic back pain. But when you have acute (sudden) back pain, putting extra stress on back muscles and ligaments could raise risk of further injury. Ask your doctor whether you should lift weights, and which exercises to avoid.
The trunk rotation stretch can help relieve tension in your lower back. It also works your core muscles, including your abdominals, back muscles, and the muscles around your pelvis.