Alot of problems with fatigue is from standing in one spot for a long period of time. At work my platform is made of raised plywood with some real crappy hard rubber interlocking mat (not my choice or my decision). On top of that I dragged a nice chunk of anti-fatigue mat. If I have to prove out a long program and stand in front of the control for hours, my legs start getting tired and my feet sore. I take small breaks and walk around a bit. It helps to get the circulation going and the muscles working.