Hey burns,
In short, the entire body is used in the shot put. Shot putting is usually a single, all effort throw that starts with the momentum of swinging your body. Numerous throwing athletes will do the majority of their training down lower body, and core exerices to increase power. Studies have shown that olympic-style lifts such as the snatch, and clean/jerks prove beneficial for increasing power, and distance thrown. Many would argue that these exercises can lead to shoulder injury, but statistics show they are some of the safest exercises. I've done a lot of work with medicine balls, doing many rotational throws or overhead throws. The key is to get your entire body involved.
Any questions on anything, I will be happy to answer.
Good luck this spring!
