Trump on Biden not coming to the King's coronation

Trump on Biden not coming to the King's coronation:
"I don't think he can do it physically. It's hard for him to do it physically. I think getting here, for him, he's got a lot of things going and a lot of strange things happen. But certainly he should be here as a representative of our country.. I think it's very disrespectful."

What do you think Trump means by he's got a lot of strange things happening?