The Afterburn Effect
Posted on May 1, 2011 by
Did you know that the more intensely you work out the more calories you’ll be burning up to 36 hours after your sweat session? See, I only push you because I care!This phenomenon is known as the “afterburn effect” and may be one of the most easily manipulated tools that you never knew you could use on your fitness plan.
This chart shows how an intense circuit training session keeps your metabolism reved up far more and for a much longer time than a traditional, or "old school", steady paced workout session. With the old school style of training, your metabolism is back to the pace of a turtle very soon after the workout is complete. With high intensity interval training (HIIT), your metabolism is fired up for up to 24 hours after your session is complete. The best news...the HIIT workout is even shorter than those long, boring, steady paced sessions and you get far superior results!
As soon as you’re done exercising, your body is working on overdrive doing two very strenuous activities: 1) it’s trying to replace an oxygen deficit that you created while working out, and 2) it’s trying to replace all the glycogen (energy stores in your body), and working to repair your muscles that are naturally torn in the process of becoming stronger.
This time period, called Excess Post-Exercise Oxygen Consumption (EPOC) or "afterburn", begins roughly as soon as you drop your last barbell or do your last jump squat. Your body is recovering from working so hard, you’ll be burning up to 50% more calories than you do during a normal day, and the effect can last up to 24 hours later. The closer to the end of the workout, however, the stronger the effect will be.
Does this mean that even though you’re not working out, you’re still burning tons more calories? YES! So already, that’s pretty darn good news! But guess what! There’s more . . .
Let’s say you do, oh I don’t know, a VIP Fitcamp class from 6:00-6:45 in the evening, which uses muscle-building resistance and strength drills in combination with high-intensity cardio drills (knocking off both of the aforementioned requirements to switch on the afterburn). And let’s say the next morning you get up around 6am, 7am, 8am or even 9am before work to go for 20 minutes of interval training: like a 5 minute steady pace warmup, then 10 minutes of HIIT (30 seconds of all out sprint followed by 30 seconds of slow paced walking...repeated back to back for a total of 10 minutes), followed by a 5 minute steady paced cool down walk. Your body is still in the afterburn zone and will burn more calories than if you did that little 20 minute jog with no workout the night before. On its own, a 15 minute jog won’t do a whole heck of a lot, but thanks to the afterburn effect, now it can.
So remember the next time you’re lifting weights at the gym or doing a push-up party in front of your TV: if you push the intensity a little bit harder, work a little bit faster, and muscle through a little bit stronger, you’ll be reaping the calorie-burning benefit for hours to come.
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