The faster you go, the greater risk you’re at for pulling a muscle or suffering a related injury. Sprints are a quick way to get your heart rate up, and it can be fun to race the clock. But it’s much smarter to run more slowly and for longer durations, especially if you’re thinking you want to continue running over the long term. Incorporating a warmup and stretching afterwards can help make sprinting safer — though even then, you don’t want to overdo it.