Interval training, metabolism boosting and EPOC

HIIT - AKA, this year's Holy Grail of exercise. In our quest for the perfect workout that will take 15 minutes and only has to be done once a week (and preferably is delegated to someone else on our behalf!), the fitness magazines and even the mainstream press have been a-buzz with talk about HIIT - High Intensity Interval Training (So, googling on HIIT training, like I just did, is repetitively redundant). So what is HIIT, how is it supposed to work, and is it for real?

First of all, HIIT isn't new. I've been incorporating HIIT into my own workouts for the last 6 years or so. It's been a part of my beginners' running program since it started. And it's been part of fitness classes like circuit training for years!!! It's getting a lot of press because it's the next hot thing and because it "solves" one of the problems we all seem to have with exercise - it's an effective workout in half the time.

So before we get into how it works (and a little bit about how to do it), let me answer the question of "is it for real?". In a word, YES! It's a highly effective technique which allows you to pack a mega-calorie burning workout into less than 45 minutes. You can select any of dozens of modes depending on your taste in exercise and can probably modify almost ANY workout routine you currently use (except maybe Yoga and Pilates) to function as a HIIT routine. Not only is it hugely effective for burning calories and boosting your metabolism, but it's capable of producing great performance strides in your "sport" if you use it correctly. (Yep, I'm a fan of this kind of workout!)

How to do a HIIT workout

Here's what a HIIT workout looks like - start with warming up with a 5-7 minute warm-up in the basic mode you'll be working in. This means light cycling if you're going to use the bike, walking on the treadmill if it's running, or doing some light weight sets if you are going to do a HIIT lifting session. Let's choose running. So, we'll walk or easy jog on the treadmill for 5 or so minutes, do a little light stretching and return to walking/jogging for about a minute. Next, push the speed on the treadmill to YOUR max. This may be 10 mph or it may be 5 mph, depending on your fitness level. Once the treadmill reaches speed, stay there for 1-2 minutes. You should feel like you can't do more. Immediately cut back to walking/light jogging and keep moving for 90 secs to 3 minutes. You should be breathing normally, but your heart rate will not be down to resting HR. Repeat this pattern for about 20-25 minutes. ALWAYS do a full cool down after a HIIT workout. Keep moving lightly till you are breathing normally and your heartrate is below about 110 bpm.

This workout is very intense, but can be done by relative beginners by making sure that you choose a mode that is attainable (walking, walking on an incline or stationary biking can all be used) and using an intensity suited to your fitness level.

What HIIT does that's so great is it increases the POST workout calorie burn. It's rev'ving up your metabolism to keep burning at almost the same rate as during the workout itself. This effect lasts 16-38 hours after the workout and a great HIIT workout can cause up to 2-3 times the amount of excess calorie burn as the original workout. The term EPOC (excess post-exercise oxygen consumption) is used to describe this effect and refers to the fact that oxygen is used in the processes used to repair and replenish the body after the intense exercise period. In addition to using excess oxygen, fat stores are broken down and consumed during this period.

Why continue to do medium intensity cardio?

as functional exercise, balance exercise and mindbody work) for my clients and just use these mega-efficient workouts? Well, here's the problem - they are INTENSE. As such, they aren't always performed with perfect form, they don't always work all the muscle groups properly, and they are anaerobic. So, doing too many of them wipes you out and you don't perform any of them to the intensity that you can reap maximal benefits. And you don't build muscle as efficiently as with a regular strength session. And you don't develop cardiovascular endurance in quite the same way as with long, moderate intensity sessions. And if you're constantly working to this level, your chance for injury goes WAY up and your ability to recover goes WAY down.

Bottom line - incorporating HIIT sessions can be a fantastic way to boost both your fitness AND your weight loss. But, you need to do it intelligently. Limit HIIT sessions to 2 times a week, keep the sessions short and use a mode that you are comfortable with (learning to run or lift weights during HIIT sessions is a recipe for injury!). If I can help you incorporate HIIT into your workout routines, give me a call or drop me an email!

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