Not warming up
Most personal trainers and group fitness instructors will tell you the most important part of class or a workout session is the warm-up. Yes, even your super-fit spin instructor will likely explain that a quality warm-up will loosen up your body, prevent injury and discomfort, and set the tone for your workout. Since runners are notorious for skipping warm-ups, there are apps to remind you to warm up before you run. (Try i.Run) And, yes, a cool-down is just as important.
Warming up on the treadmill
At least you’re warming up, right? “Wrong,” says Michael Moody, Chicago-based personal trainer and author of Redefine Yourself: The Simple Guide to Happiness. “While ‘warming-up’ on a treadmill may increase the blood circulation to your muscles, it limits your range-of-motion even as you seek your full stride.” This is a problem because, as he says, you may strain the muscle you hope to open, which will result in less range of motion. What Moody suggests instead: low-impact exercises including body weight lunges, squats, and hip thrusts before hopping on a treadmill to run, jog, or power walk. Here’s an easy stretching routine to try.