“The biggest mistake people make is not sleeping enough,” says Lim. “They sacrifice sleep in order to do more work” by waking up early to jam in a bike session before work. But your body cannot adapt from training, let alone recover, without adequate shuteye.
The Fix: Ditch the complicated periodization formulas and let your sleep dictate your training schedule, says Dr. Lim. When you’re feeling tired or had a late night, cut down on volume and intensity, but amp up the intervals when you’re feeling rested. “It’s way better than any complicated math,” he says.