hyperextension
Bending you head back until it hurts is an example of hyperextension. Hyperextension occurs when the joint is opened beyond it's normal range of motion and may make the joint unstable or increase risk of dislocation.
hyperextension
Yes, Until you stop bending it back and it becomes potential energy.
bounce on a trampoline until your back hurts
Mechanical energy is converted to heat.
if it hurts your back to bend over when your back hurts
if it hurts if it hurts
Because they will try to nurse their mother until they hurt her or she starts to fight back and hurts them.
If you want something to help heal it, try stretching (fetal position, touching your toes, bending backwards, etc.) If your back is not better after about 5 days, or it hurts too much to do these stretches, visit a doctor or local chiropractor.
Try simple yoga techniques, but be very gentle and don't do the back bending exercise (forward, dip, backward) Use some common sense. If it hurts STOP.
Spring back is the amount (could be measured both linearly or angulary )that the material has returned back to its original position after the bending process.
Planking will strengthen your back, as will stretching your back; lean forward as far as you can until it hurts hold the position until for 25 seconds or longer and repeat daily until you no longer feel pain going into positions you could also lean to the side and backwards.