QB's don't throw many curves, sliders, split fingered fastballs Ect. Different grip might be biggest thing, even bigger than motion. The smaller the object you throw, the more strain you put on throwing muscles as you grip it smaller and tightest. ( make a fist and swing your arm hard, relax your fingers and wrist and do the same... Notice a difference around your forearm and elbow?)
Not as many fast balls, but many throws with an arc
Different motion
800-900 about the most in game throws a QB makes in pre, season and playoffs
MLB starter does that in 2-3 months
Different motion
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