At the risk of overanalyzing a tweet, this is actually generally good advice. Scanning your body to release tension is a common stress-reduction coping skill taught in therapy, and in clinical settings is often referred to as “progressive muscle relaxation”, which has been shown in many studies to reduce stress in the short-term. If you google this term, you’ll have better results.
Here’s an NIH article that covers a few things, including progressive muscle relaxation:
It’s not intended as a permanent solution for underlying causes (e.g. doing coke or alcohol, like you said), but more of something to mildly reduce stress/anxiety in the moment.