This video demonstrates an exercise to strengthen extension of the trunk.
In case you cannot see the video, here is a still sequence -
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Lie on your back on a firm surface. Bend the knees to 90 degrees and firmly hold a soccer ball between the knees. |
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In an 'unwinding' movement, slowly lift the buttocks and lower back. |
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Hold this position for a few seconds. |
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Slowly allow the lower back and then the buttocks to 'unwind' to the resting position. |
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Relax, and then repeat ten times. |
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