Let’s get one thing straight: warming up is not optional. But it’s also not just jogging slowly for five minutes or swinging your legs around a few times. A proper warm-up primes your body for performance, helps prevent injury, and sets the tone for the entire run. And yet, most runners either skip it, rush through it, or do the wrong kind of prep altogether. Here’s what the research — and years of working with runners at every level — says about getting it right. What a Good