Exercise, by itself, doesn’t make you stronger. When you exercise, your muscles break down, and the only way to build them back up is by resting. This is true for all types of exercise, including Sprint 8. If you don’t give your muscles time to recover after sprinting, you won’t get the full benefits of the workout.

When it comes to Sprint 8, there are two types of recovery: mid-workout and post-workout. When you recover mid-workout, you’re giving your body 90 seconds of rest before tackling the next sprint. When you recover post-workout, you’re allowing your muscles to rebuild themselves. Both types of recovery are extremely important and should never be skipped. Here’s why:

Mid-Workout Recovery

Sprinting is anaerobic exercise. In other words, it causes your muscles to run out of oxygen, forcing them to use lactic acid as a source of energy. Lactic acid causes a burning sensation in your muscles, and you can’t get rid of it until you start getting oxygen again.

This is called oxygen debt, and it’s the reason you can’t sprint for more than 30 seconds at a time. Your body won’t let you sprint until you’ve repaid the oxygen debt, and the best way to do that is by reducing the intensity of the workout for 90 seconds. This should give your body just enough time to repay the oxygen debt.

If you feel like you need more than 90 seconds of rest, feel free to skip a sprint. It’s more important to repay your oxygen debt than it is to complete all eight sprints in one session. If you feel like you need less than 90 seconds of rest, you probably aren’t working hard enough.

Post-Workout Recovery

High-intensity exercise puts a lot of stress on your muscles, causing them to develop microscopic tears. These micro-tears are the reason you feel sore after a good workout, and they’re also the reason your muscles get bigger. When your body repairs these micro-tears, it builds up the muscle tissue, making your muscles bigger and stronger than they were before. But this only happens if you give your body plenty of time to repair your muscles. Otherwise, they won’t get bigger, and you could hurt yourself. This is also true for sprint 8. You should rest for at least one day between workouts to give your body time to repair the micro-tears in your muscles. Give your body a chance to rest. Your muscles will thank you!

Phil Campbell

“Sprint 8 is a tried and true workout that can rapidly and radically change your body for the better. It’s simple. It’s effective. And you’re going to love what it does to your body.”