Originally Posted by westofyou
Guys with big butts/trunks are the horses, they tend to use the legs to carry their body through the mound, hence why so many pitching coaches (save Johnny Sain junkballer) like to make pitchers run. The fatigue factor will differ by body type and the move away from healthy mechanics might be perceived as being part of the fatigue factor and the leash might be shorter for the guys whose arms take more of beating when they stray from their mechanics. I don't think there is a blueprint for fatigue with hurlers that one can see without watching almost everyone of the guys pitches
My pitching coach in high school once told me, "kids tend to pitch with their arms, professionals pitch with their legs."
I do believe this is a big deal. That's not to say that if you work hard on getting push with your legs you can't hurt your arm, but you most definitely minimize the stress/fatigue on your elbows and shoulders.
I pitched (ineffectively mind you) a ton in high school. I probably was overworked. I was one of the only guys on our team that constantly threw strikes, so I was used a lot despite a slow, looping curveball and a pedestrian fastball that I felt my grandmother could outrun. I did have a good circle change that got a lot of movement, but it most certainly wasn't a devastating difference in speed from my FB.
Point is, I threw an awful lot and my arm never got tired. When I say a lot, I mean it wasn't uncommon to start twice or three times a week and the first two starts I'd often pitch 5, 6 or even all 7 innings. I got tired once in a while, but never really became "sore" the next day.
My mechanics, despite not starting to pitch until I was 14 years old, were pretty good. Still, I attribute most of it to simply being able to handle the wear and tear. Obviously that's not to say this is remotely comparable to pitching over 200 innings at the Major League level, but I think it shows relative to my peers, I was able to handle more pitching than many -- an indication that pitch counts and charted innings can sometimes be overrated.