Ok so by now you have probably heard about High Intensity Interval Training or HIIT. Basically what you are doing in your workout is alternating between high intensity like a sprint on a treadmill, going as hard and as fast as you can possibly go, then recovering for a period of time so that you can go hard and fast again. Programs like Insanity are based on HIIT. There are many studies out there about the benefits of HIIT and how working out for a shorter amount of time with varying intensity levels actually works better than jogging on a treadmill or using an elliptical for an hour. Here's one study you can read about https://www.unm.edu/~lkravitz/Article%20folder/HIITvsCardio.html In the above video my client Devon gives a brief demo on how to do HIIT on the treadmill. While the video only shows one interval, you would want to do several of varying intensities and recovery periods. I always tell my clients to recover from the high intensity for as long as necessary so that when they bump up the intensity again, they can go for it with 100% effort. So there you have it. If you're not doing HIIT in your cardio workouts, you're missing out on some major benefits and results.