Tightness through the pectorals (chest muscles) generally creates rounded shoulders. This common problem is rectified by massaging the muscle therefore enabling you to find and maintain the correct address position.
Allow your body weight to push into the ball and stop when you reach a perceived tenderness level of 6/10. Hold the position for 10-12 seconds and the tenderness should have reduced. Move to a different area then you can roll across the muscle as an alternative method.
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