This waist training vest is the absolute best!!! I am 5'10 and at 172 lbs. I ordered an extra large.  My normal size is a large.  A XXL would have been too big and would not have serve the purpose. It is designed to be worn close to the body. I wore the vest when I was out walking and when I returned home, my shirt was soaked to the end.  It is best to wear a t-shirt under the vest for comfort sake and to wick off the sweat.  I am very pleased and saw some results from it. This is the very first produce of this kind that I can say it actually works.