FYI, this training is part of USAF basic training. With more yelling. I wouldn’t call it a pleasant routine, but it’s certainly effective when you do it for six hours straight and start to get an adrenaline surge when your alarm goes off.
That still persists 1.5 years later, so it may be a munchkin hack in itself.
Learn some basic voice production for stage techniques. How your voice sounds is an absurdly strongly weighted component of a first impression, particularly over a phone or prior to direct introduction, and being able to project your voice in a commanding fashion has an overpowered influence on how much people listen to you and consider you a ‘natural leader.’ In particular, learn what it means to speak from the diaphragm, and learn some basic exercises for strengthening your subsidiary vocal chords like Khargyraa and basic tuvan throat singing, and you’ll be surprised at how much it makes people sit up and listen. You might coincidentally have your voice drop into a lower register after about a month of such exercises, it (anecdatally) happened to me and several people in my voice production for stage class in college. (class of 25, 6 people had their voices drop within the first 4 months, teacher said those numbers were normal.)
Most people just assume you’re born with a voice and have to deal with it, which is demonstrably untrue, and so they consider your voice to reflect your character.