The world seems to be discovering the greatness of the HIIT (High Intensity Interval Training) workout, and for good reason – it’s unbeatable efficiency is the perfect fit for today’s world of deadlines and busy schedules. So how exactly can you make the most of these short workouts? Are you REALLY doing HIIT the way it is supposed to be performed? Let’s find out.
High Intensity Interval Training
Just to refresh your memory, HIIT is exercise performed in short bursts of intense intervals, using large muscle groups. These short bursts can vary in length, but the shorter the time period, the more intense they should be.
HIIT workouts can range from just a few minutes (read about Tabata protocol here) to about 20 minutes or even longer, depending on your level of endurance and your goals. Just a 12-15 minute HIIT workout, done at the right intensity, can be all that is needed for a fantastic cardiovascular AND strength training workout.
Intensity is Key
The MOST IMPORTANT thing to remember about HIIT is that during the intense intervals, you should be pushing yourself as hard as you possibly can. This is not going to feel like steady-state cardio where you might be able to talk or look around and let your mind wander.
You will need to push yourself to a point that you are breathing heavily, your heart is pumping, and you can’t think about much else besides performing another rep of your exercise. An easy way to find out what this feels like is to hit your local track and pretend like you are in a race – sprint as fast as you can possibly run until you feel your body run out of steam, probably after 5-10 seconds.
With this one sprint that took just a few seconds, you have now activated the systems of your body that will send you into fat-burning and muscle-building mode for the next 24 hours. You can now transpose this feeling to pushups, cycling, swimming, burpees, squats, plyometrics – any exercise that you can perform and ramp up the intensity, either by adding weight, speed, or difficulty.
So while hopping on a treadmill for 45 minutes and running at a steady state may burn 300 calories vs. a 12 minute HIIT workout only burning 150 or so, the minute you step off the treadmill your body dramatically slows down the burning of calories, so 300 is about the best you’ll do. With HIIT, you’ll continue to burn massive calories for up to 24 hours on top of the 150 during the 12 minute workout. It’s like turning on a fat-burning program that runs in the background while you go about daily life.
Change It Up
Another important thing to remember is that maximum fat burning takes place when you are consistently making your body guess what is next. The more you can “shock” your body, the more it will scramble to recover afterwards, activating the all-important EPOC effect – excess post-oxygen consumption.
This means your body creates a deficit of oxygen during exercise that it will need to “pay back” over the next 24 hours, using your fat stores to fuel the process, which is why you keep burning calories. So what you don’t want to do is the exact same HIIT routine performed at the same intensity over and over.
Switch it up by trying new workouts as often as you can, at varying intervals. One day, go to the track and do 10 sprints. The next time, do plyometric drills in 30 second intervals for 20 minutes. The possibilities are endless as long as you are working at a high level of intensity.
Take a Break
The other important component of HIIT is the rest factor. During the breaks between the high intensity intervals, it is vital to rest. This gives your body the chance to re-start your energy producing systems so you can hit the next interval with intensity again, maximizing your effort and thus your fat-burning. If you don’t feel like you have to rest, you’re not performing your high-intensity intervals as hard as you should be or you’re ready to move on to a tougher level.
It’s also important to have rest days in between HIIT workouts to give your body the chance to fully recover. If you don’t fully recover, you won’t be receiving all of the benefits that HIIT has to offer, and you won’t be able to perform each workout at max effort.
HIIT can also be very shocking to your central nervous system, and over-doing it can cause major burnout and too much of a negative energy balance. This is especially important when you first begin HIIT. Once you work up to it, you may be able to do these workouts more often. Until then, it’s best to have complete rest, active recovery, traditional strength-training, or endurance cardio in between your HIIT days.
Eat for Your Workout
If you’re doing HIIT workouts often, you’re going to need to eat the right foods and the right amount of calories to fuel this high level of activity. For the best performance, eat a small meal with carbohydrates about an hour before your workout.
The carbohydrates will be easy on your stomach and will give you the extra energy you need to get your body performing at its top capacity. After your workout, eat a protein/carb meal as soon as you can to help your body replenish your muscles.
If you are noticing that in between workouts you feel sluggish and/or overly fatigued or sore, you may not be eating enough calories to match your new level of intensity. Too much of a negative energy balance (the gap between how many calories you’re taking in and how many you’re expending) can cause all sorts of problems, including your body refusing to let go of fat. If you’re going to work out like an athlete, you’re going to have to eat like one!
So it’s pretty simple: ramp up your intervals so you are reaching your maximum effort, eat for your activity level, and rest efficiently between intervals and workouts, and soon you will be getting the results you’re looking for. Enjoy, HIIT is one of the most fun ways to keep exercise interesting!