TJ, earlier in the thread you mention biceps in reference to steering. Wouldn’t biceps be used if pulling the wheel and triceps used if pushing? I guess using both would be more of an arm locked method.
I always like to note what were my physical weaknesses are so that I can work on them with training. Sometimes I do feel it indicates that I have a driver comfort issue or a change in method is needed
In my first race day my brother said he could just see when things physically got me. You looked OK, then next lap you looked like a sock monkey. I have found once I start fatiguing to the point my head position starts to fade with less and less laps it become a sign the end is near.