As I took the Active B' protocol, I progressivly lost strength and muscle endurance. I took Magnisium, but it did not have a direct effect on it: However, I continued to take it as a part of my regimen. With in 4 days of taking 2000 L carnitine, I have started to regain my strength (not where it was but making progress). I am taking equal doses of Fumerate and tartrate. As I know others have had issues with this, I will update if anything changes.