Personalized Fitness Fanatic Workout Exercise Youth T-Shirt. Fitness fanatic Youth T-Shirt - Heather outfit for anyone who enjoys a trip to the gym for a serious bit of exercise and a good time working out. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.