Move your arms in a freestyle swimming motion. Feel the tension of the muscle in your back, towards your sides.

Answer The paraspinal muscles, sometimes called the erector spinae, are three muscle groups that support your back. You use them every time you lean to one side, arch your back, bend forward, or twist your torso.:Thinking further, I recall that the way the body causes a muscle contraction is related to firing a nerve. It's a matter of activation energy, in a sense, and when you're talking about many muscles working in concert you're talking about an aggregate of muscles trying to do whatever they are doing at the same time.

I suspect that because that particular posture is an atypical one, your body is not as accustomed to dealing with holding that posture statically--i.e. what is view as "static" but is actually an aggregate of many muscles working in concert and simultaneously.

Thus what it does is attempts to hold the position that you're requiring it to do, but it doesn't "know" from experience how to do that 'precisely.' Thus the many muscles working together don't really work as 'precisely' as they would had they more experience with the posture,When sitting in an office chair for a long period, the natural tendency for most people is to slouch over or slouch down in the chair, and this posture can overstretch the spinal ligaments and strain the discs and surrounding structures in the spine.

Explanation:

answer; i believe that the correct answer is (participation);