These shirts are awesome. I originally ordered three of them along with two other brands all in size (Xl).The other brands (Russell and Champion) I ended up selling because of very loose fitting. The adidas however were 100% perfect, they stretch and  are light but strong with great moisture wicking properties and are simply very nice to look at. I'm in to p90x, beach training, beach tennis  and mountain biking. Adidas Techfit is definitely my activities shirt. Hey did I mention that I ordered seven more? Yes I did !!! Luv em.