Periodically, When I Reach Forward With My Left Arm, I

Periodically, when I reach forward with my left arm, I occasionally experience what I can only describe as a very sharp and intense tearing or burning sensation on the outside of my left forearm. I also occasionally experience this sharp burning/tearing sensation on the outside portion of my right foot. The pain is only temporary and will be difficult to reproduce immediately. Both locations seem to occur after I have been resting for a period of time. I have no loss of coordination and seemingly do not have a loss of strength with the tearing/burning in my arm or foot. I can't seem to find anything online that is even remotely similar to this. Both areas seem to be muscle regions and not tendon or ligaments.