Most exercises, he said, can be made as easy or as challenging as a person can handle. There are as many workouts as there are different areas to do them in. One of the keys to medicine balls is making your body balance itself in an unbalanced environment. When you are lifting groceries, you bend down low and then raise them higher on a shelf. Medicine ball training uses those applications, whereas something like weight training isolates muscles in movements the body never uses.
Balance is tapped for strength, too.
For example, I placed one hand on a ball and did a few push-ups. My arm shook in tiny jerks. That was the right reaction, said Messenger, because the shaking is my body being off-balance and then balancing itself. With medicine balls, we use all planes of motion. Innately, you already know all of this stuff.