The Janji Runterra Bio Muscle Tank gives you an eco-friendly top to sweat in that won’t clog up landfills when it wears out. This synthetic-blend running shirt biodegrades like a 100% cotton tee thanks to the specifically-formulated 37.5® polyester that can break down in four years (but only in an anaerobic or oxygen-poor environment), so it breaks down in the landfill, not your closet. Conventional polyester, on the other hand, takes more than 400 years to break down. Not only is this shirt environmentally friendly, but it is super soft and comfortable thanks to the premium cotton in the blend. The 37.5® polyester also has microscopic volcanic ash that gives you enhanced thermal, vapor and odor regulation, so you stay comfortable all run long and don’t need to wash it quite as often. The shoulder seams are rolled back off the top of the shoulders for ergonomic comfort, while the slightly cropped silhouette hits above the hip for a stylish look. The top is made from 70% natural fibers, so some shrinkage may occur. Whether you are going to the gym for strength training or running on a treadmill, the eco-friendly Janji Runterra Bio Muscle Tank will show off your arms and feel great on your body.