While some of the world’s top athletes (swear/sweat/swelter) by a rigorous warm-up, others have (mix/cast/hurtle) real doubt on the practice by admitting that they don’t attach much importance to it at all. Several major studies have indicated (which/how/that) static stretches such as touching your toes (grow/yield/make up) no discernible benefit. In fact, extending the limbs in this way for too long can actually (impair/repair/rejuvenate) performance on the track or in the gym.