The reason your back may hurt after staying seated for long periods of time is that it puts a lot of stress on the spine, fatiguing and overstretching the ligaments.1 Sitting also tightens your hip flexors, which affects your pelvis and can increase the load on the lower back. Important both for general well-being and for exercise, since a tight back can lead to injury, being sure to stretch your lower back can help stop back pain by relieving tired back muscles, and taking the pressure off your backbone. To avoid injury and stress, check out what our experts share as their favorite ways to stretch the lower back after sitting all day. Click to see these Great Stretches