For running, the gym, and other sports, the best clothing is one that you hardly notice is there. The short-sleeved training shirt Rukka Maatta is made from a lightweight, four-way stretch fabric that minimizes weight and does not cause a tight feeling when moving. The fabric wicks moisture away from the skin, so you don't feel uncomfortably sweaty. The shoulders, sleeves, and center back of the shirt are made from extra-breathable mesh fabric.