Personalized I Heart Gym Toddler Long Sleeve T-Shirt. I heart gym text with an edgy heart and the word gym wearing sneakers is a fun design for gym and fitness lovers on birthdays, holidays and back to school. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.