Why: Stretching while the body is cold (has not been moving) is a very bad idea. Warming the body up with some light cardio prior to exercise is much more effective. Stretching cold muscles and connective tissues can lead to injury. Remember, your body is very much like a car when it comes to movement. The more your warm it up, the better it works. Your body has lubricating fluids (Synovial Fluid) that sit in the joints (just like a car has oil that sits at the ready to ensure that all of its components operate effectively), and, when gently heated up prior to rigorous movement, will help prevent injury and ensure better performance.