Trevor Raab You should stretch! Runners are told this all the time. But that can lead to a lot of common questions, like: When and how long should you stretch? Which stretches should you do? Does a warmup or cooldown routine count as stretching? Will stretching really help my running? The Runner’s World Guide to Stretching and Mobility will help you put together a program that fits you perfectly. Tight hips and shoulder pain? We got you. Want your prerun warmup to add a boost to your stride? Done. Your Stretching and Mobility Glossary Most runners use the terms stretching, flexibility, and mobility interchangeably, but they are three different things.…