system
Given the following post, respond as if you're commenting on Reddit:
human
Why is fatigue an adaptive response to anxiety?

This^
gpt
There’s a causative relationship due to the energy used to activate the sympathetic nervous system. Fatigue would also stop one from engaging in whichever behaviors or situations trigger the anxiety. This, along with the isolation and lack of motivation, is also commonly seen in anxiety disorders (and depressive disorders) as a protective mechanism to avoid the sources of harm or perceived harm.