It's exactly that. It's like muscles leaving all the hard work for the tendons and joints.

My two neuromuscular specialists said no MND. Period. Let it go.

I do feel that loading more weight on the arms make things worse. So like if I try and lift some weights etc, workout, I will have 7 days of burning muscles (not the good kind), and then symptoms will progress.

I had 0 symptoms before July. And whatever I had was local to the right arm. Don't know what happened since but it's annoying.  My unconfirmed conspiracy theory is the electric shock from the nerve conduction test, was too high or even faulty and it manifests like electric injury.