This is bulshit. That one one the top is stretching your stomach muscles and compressing your back muscles.
No. I injured my back when I was 16 and it wasn't treated, so now my upper back, neck, between sholderblades gets stiff, sore and sometimes spazms.
Momz, (the sports medicine BA) taught me this exersize which I do every morning.
It's kind of like a crunch but don't go up that far.
-Lay on your back and lock your fingers around your kneck
-pull with your arms and flex your stomack muscles into a semi crunch, but dont come up off the floor.
-then back down. Do it slowly and pull as hard as you can then relax. repeat.
when you are in the pulled all the way position you can gently rotate your sholders to stretch some smaller muscles. Don't get crazy and tare anything.
The point of this is to stretch out the long muscles that line your spine, your kneck and the muscles atached to your shoulderblades (that get jacked from bad posture). The crunch part gets blood circulating in that area to repair damage.