The idea of doing what are known as the supine flexion exercise to increase spinal disk height and relieve lower back from disk decompression is an idea which I actually forgot about which would definitely work.
From WikiAnswers the Supine Flexion exercise is defined as “supine flexion is lying in supine (on your back) while “flexing” (bending) your knees into your stomach and keeping your head off the floor“. Refer to the picture to the right.
From the Clinical Study “Interventional Study of Effects on Spine Height With Two Unloading Positions” we see that these researchers were actually testing to see how useful it is to do this exercise to restore spinal torso height and decrease lower back pain and other pains which might be in the upper leg area, probably due to either bulging disks, herniated disks, or sciatica.
The way the subjects did the exercise was by….
“…lying on their back with hip and knees flexed to a 90 degree angle. The height of each person will be measured before and after completion of each intervention using a specially designed measuring tool…”
“…The subject will lay supine with the legs supported by a foam wedge with hips flexed to 90 degrees and knees flexed to 65 degrees. They will maintain this unloaded position for 15 minutes.”
From the same PubMed study cited in the previous post about Aquatic Vertical Suspension, Immediate changes in spinal height and pain after aquatic vertical traction in patients with persistent low back symptoms: a crossover clinical trial, the result was that after going through with this specific exercise where the lower vertebrate bones are completely unloaded, the height increase is 4.21 ± 2.53 mm.
Supine Flexion is a good land based stretching exercise to gain temporary height. It however is not as good in getting temporary height as using the Aquatic Vertical Suspension technique, which is only slightly better by providing about 1-2 extra millimeters. In addition, the water way of unloading the body seems to show better results on reducing pain and reducing the compression of nerve endings. I would guess that the smartest way to get as much height increase as possible is to do BOTH types of exercises, to unload the lower back region on land and in water.
So to get some noticeable height increase very quickly, like Tyler said, do both the Supine Flexion stretching when you are on land and when you decide to go swimming or to the pool, carry some weights with you to try out the Aquatic Vertical Suspension.