4-8 Breathing Exercise for Good Sleep | Relax Your Shoulders This 4-8 breathing exercise may help you unwind and drift off more easily. Relax your shoulders as you exhale to let go of tension. Step-by-Step Instructions Inhale through your nose for 4 seconds Exhale slowly through your mouth for 8 seconds, letting your shoulders drop and relax Science-Backed Benefits Longer exhales stimulate the vagus nerve and boost parasympathetic activity. Slow breathing can help lower heart rate, reduce stress