Straight from yoga: touch your toes and then stand up with a rolling motion of the spine.
Stand with your feet shoulder width apart and toes pointed slightly inwards, knees unlocked — this is not a hamstring stretch. Breathe steadily for the duration of the exercise. Begin by lowering your chin to your chest and continue to flex your intervertebral joints one at a time. The lower parts of the spine should remain erect for as long as possible. Continue until your entire upper body is hanging from your hips, and make sure your head is a relaxed dead-weight at the end of the spine. At this point, you have two choices for getting back upright: for the first 3-5 repetitions, you should (a) squat down, slowly straighten your back, and then stand up using the strength of your legs; but once you are warmed up a bit, you can (b) simply reverse the spinal movement instead, rolling up instead of down, lifting the vertebrae back into place one by one, starting with the low back and moving upwards.
Good for …