Middle age is when work is a lot less fun and fun is a lot more work.
Don't worry about middle age: you'll outgrow it.
Middle age is when it takes longer to rest than to get tired.
Middle age is when you stop criticizing the older generation and start criticizing the younger one.
Middle age is when anything new in the way you feel is most likely a symptom.
Middle age is when the best exercise is one of discretion.