I recently started doing some wrist exercises (flexing my racquet 180 degrees from horizontal forward to horizontal back, 200 times). I noticed after starting that my wrist is creaking with each movement - it sounds like knuckle cracking, but at a higher pitch and only about 1/3 or 1/4 the volume of a cracked knuckle. Should I have any concerns about this? Should I modify this exercise in any way. I am feeling some discomfort in the wrist, but I think that is only muscle fatigue from performing a new extercise. Thanks for your help.