Awkward postures held for long periods of time place high demands on the muscles that support the spine. Keeping the spine bent forward for long periods may deactivate key back muscles. Like a loose guitar string, the normal level of tension in the elastic tissues of the back is also reduced. This leaves the spine vulnerable to injury.
After just 20 minutes of uninterrupted bending, researchers have observed spasms in the back muscles. These spasms suggest that some kind of damage can occur during periods of prolonged forward bending.
What's the solution? Lots of rest. After 20 minutes of bending, even seven hours of rest might not be enough. Researchers think that 24 hours of rest may be needed to fully restore the strength of key back muscles. Without sufficient rest, the tired back is susceptible to injury. Using good body posture and frequent rest are two important ways to offset the potential injury and pain of staying in a forward-bent position.