Why do joints ache when the weather changes (rainy days)?

It's cold, but people's bodies are very sensitive.

Cold air invades, and the injured part reacts and hurts.

My mother's heel is very dry, it hurts from time to time, and it is easy to crack, which is much more accurate than the weather forecast!

Every time she gets hurt, she tells me to change the weather.

My grandmother fell on her knee when she was a child, and it hurts every day.