Do you sleep in different positions on a nightly basis? Chances are the answer is yes—and that’s common. There isn’t any one sleeping position that works for everyone. Some people prefer to sleep on their side, others on their back. Your usual sleep position — along with other factors, including your weight— can strain your back and contribute to development of back pain. Sleeping positions also affect existing back pain, either by letting you sleep comfortably or by making you wake up sore and achy. Similarly, back pain is more likely to keep you awake when your sleeping position provides no relief.