Casting: Keep Your Elbow Low
Sore shoulders and arms could be indicators of poor casting technique. And as Sam Hudson, a self-proclaimed “Lefty Kreh casting disciple” urges, take a look at your elbow and keep it on the shelf: “meaning going through the entire casting sequence, from line pickup to forward cast, with the elbow low, on an imaginary shelf, at the height where your elbow would be with your arm hanging at your side.”
This low arm position minimizes stress on the shoulder joint, as well as tightening loops and increasing line speed. So take a look at the article, the demonstrating photographs, and then at your own technique.