Exercise trends have changed a lot over the years, and it can be difficult to keep up. For a very long time, it was assumed that if you wanted to bulk up, then you lifted weights – but if you wanted to burn fat and slim down, you did 60 minutes of cardio, five times a week.
Now that better research is available to us, we are discovering that neither one of those statements is completely true. Not only that, but it turns out there is plenty of daylight between heavy weight lifting and heavy cardio, and in fact, the sweet spot for fat loss may exist somewhere in the middle.
High intensity interval training, also known as “HIIT” is a training approach which usually consists of a brisk 5 to 10 minute warm-up, and then alternating intervals of “sprinting” and resting. In this case, the word “sprinting” does not only refer to literal running, it’s more shorthand for giving a workout you’re all – meaning you are going between 90% and 100% of your personal capacity – but only for about 60 seconds at a time.
It seems counterintuitive, doesn’t it? In the time it takes you to do six or seven of these sprint/rest cycles, a fit runner could have completed a 5K. Is it really true that the interval trainer experienced more fat loss? Science is saying yes.
Your Body Responds on a Cellular Level
Recent studies on cell metabolism indicate that people who work out intensely for short periods of time, followed by active rest periods, experience a fundamental change in their DNA. This study is literally saying that interval training is so effective, your body rewires itself to meet the demands of the workout. People who engage in interval training have muscles that are better designed for strength, and their metabolism is more geared toward fat burning. Pretty amazing, right?
You Are Less Hungry after the Workout
Those who work out regularly may have already experienced the phenomenon of post workout appetite suppression. Studies are showing that those who engage in interval training experience this effect for much longer than those who do only weightlifting, or only cardio. You are less hungry, less likely to snack mindlessly, and therefore burning more fat.
Active Recovery Happens During Rest Periods
The rest periods that happen between sprints in HIIT workouts are meant to be “active rests.” This means that you are still pacing, pedaling, rowing, etc., just at a very easy rate. Continuing to move while you recover keeps your body primed for fat loss.
Your Body Is Built for This
Scientists are now coming to understand that human beings have evolved over thousands of years to engage in precisely this kind of activity. Think of it in terms of a hunt. Our ancestors needed to be prepared for moments of intense chasing (or fleeing, as the case may be) followed by active rest periods of tracking and searching. Your body is built from the ground up to sustain short bursts of all-out activity, and prolonged periods of active recovery.
If you have been on the fence about trying interval training, hopefully this list gives you the knowledge you need to get started.