How do I relax tense muscles at nightime?

PMR. Progressive muscle relaxation (pmr) is a relaxation exercise that decreases muscle tension. You can do this while in bed. It works by actively tensing up and relaxing one muscle group at a time. Areas traditionally covered are legs, abdomen, chest, arms, shoulders, neck, forehead, and area around eyes. Diaphragmatic breathing can also help you relax and help you fall asleep.