The term for this among magicians and mentalists is Hellstromism. Axel Hellstrom pretty much invented muscle reading. Now and then you can find the original Hellstromsim (Nelson Publications) book on e-bay-- the Amazing Kreskin used this technique to find his 40K paycheck on live tv for years.
There are far better texts on becoming a human thought reader. My personal resource are police interrogation books...the expensive hundred dollar ones they wish only they could get their hands on. Well, Amazon will sell them to you, no questions asked. Micro-expressions are the key to this dark art, and they determine whether the cops will keep showing up at your house everyday for months on end to toy with you until you break, or leave you alone. They're also great for tormenting your teenage daughter (a GPS in the lining of her purse doesn't hurt either...lol).
soooo should I buy it