Male Speaker: Okay, now is interval for power dominant sports. Now what you do is very simple. You dash 50 meters as hard as you can and then you come back for 120 seconds for full 2 minutes slowly recovering breath. Because it's very taxing on the oxygen system, its very hard on the muscles. Now very important to say, if some guys hear things that you can build muscle out of doing cardio vascular this is it. This 30 second sprint I just did is equal to 6 breaths. Now if you want to get little muscle mass. Combine both and you are golden.