What could cause tongue muscle fatigue when chewing? my tongue feels tired and cramps some when chewing. i dont have pain any other times other than eating. no sores or lumps. can swallow normal. potential for bulbar onset als?

The tongue isn't actively involved in chewing but does play a role in moving food so it can be swallowed. The massiter muscles.and temporomandibular joint are more apt to fatigue in chewing. I did have one case of severe lingual fatigue which turned out to be an early manifestation of Parkinson's disease. A specialist in oral pathology at a university hospital can evaluate and advise you further.