I can't remember if this was patched or mentioned before but this was a bug I found like awhile back and thought it was patched.
Basically you do some action like cutting a log or chopping a tree and as your stamina starts going down you hit the drink key and then you drink at the same time you do the other action so you don't run out of stamina. Not sure if this was intended but seems like a bug since you can do two actions at once.