I found this article recently that I thought was pretty interesting. It’s about massage and the often used phrase “you’re really tight” by therapists.

Statements like “you’re really tight” are a bit of a verbal tic, something automatic — even expected — that massage therapists to say to pass the time and make conversation with clients. Tightness doesn’t even actually have a clear meaning.3 In this context, it is trivial and harmless.

Being “Sung” (translated as “relaxed”) is one of the things we get told to do all the time in Tai Chi, and it’s open to a lot of misinterpretation. Really, what it’s talking about is not overly tensing muscles, so that the power of an incoming force can be directed to the ground without the muscles taking the load. If you can get the ground to take the load then your muscles are free to do other things.