A simple bat & ball set was just about the first thing I bought when I started exploring toys which could help me unlock movement to start pushing back my Parkinson's Disease symptoms. Once I began to play with them while my PD drugs weren't working - in an "off" state in which I didn't have my much access to movement -  it was a complete revelation! The shear degree of movement that suddenly came back in just playing "keep it up" with the bat and ball was a joy, especially in terms of neck movement and core rotation. The fact that while I was doing it, much of my other symptoms (rigidity, unfocused eyes, breathing problems, pain) went away,  at least in the moment of play, was massive in re-thinking about my condition, and how to live well with it.