Tearfulness can be a symptom of depression.
The aging process can bring with it its own challenges. I expect if we stopped to think about life and our existence it could feel extremely lonely and overwhelming.
Has the gentleman relayed any issues that are of concern to him?
Agitation could drive hyperactivity.
I feel like I'm missing something.
I wish you and this elderly gentleman all the best.
J
My best guess is that this man is just simply thinking about life and feeling deeply about what was, what might be, and what lies ahead.