Bought this for my son for fashion not sport. Excellent quality and nice simple design so can be worn for casual purposes.
My son is a 38 chest and the medium fits him perfectly. The sizes come up on the smaller end of the scale. I think if you go to the Macron website they have a very good size comparator and explanation to help you make the right choice.
Teh macron web site has some freebie offers but shipping to Ireland was dearer than price on Amazon with Parcel Motel.