In the last few days, I’ve been asked several times about HIIT. Obviously, high intense interval training was not the expected answer. 🙂
So what exactly is HIIT?
The textbook definition says high intensity interval training, meaning that you’ll gonna perform a number of high intensity exercises, each immediately followed by periods of recovery. The high intensity exercises can vary from between 5 – 10 seconds to minutes. Likewise, the periods of recovery can vary in duration too. It’s a kind of workout that can’t be boring, as you won’t have time to think of anything else except what’s next, maintaining the proper form, and making the most out of the recovery period.
To get the maximum results while HIIT training, it’s recommended that the high intensity intervals to be really intense (90 % – 100% of maximum ‘safe’ heart rate – I will come to that later within this post), as intense as you can bare. The recovery period follows, while you’ll be doing some very light exercise, like jog in place, boxer shuffles or walk around. It’s really important not to stop – always keep moving, slowly or not, but please don’t suddenly stop.
Let me give you an example of a typical HIIT workout. The warm-up and cool down are not included, so you’d want to dedicate around 10 minutes more. And you’ve got yourself a 17 minutes kick a$$ workout!
Why HIIT? | Benefits of HIIT
HIIT is extremely efficient. It lets you get a excellent result with little time spent on working out. As I am a mom, I have a family life and a full time job, so is really important. Most of the time there’re just not enough hours for all the things I’d like to do in a day. So I turned to HIIT because working out like this is really efficient. My workouts vary between 20 – 35 minutes per day, so it’s really easy to squeeze it in my daily schedule. Because it’s so short, you will be working hard the whole time.
Lots and lots of studies and researches show that HIIT training burns more fat than constant pace training. During and after the workout. (Yes, after, you read right! :)) It also trains the heart, as you have to push into the anaerobic zone. Best part is that you don’t even need equipment, because you are working with your own body weight; or if you need some equipment, it’s a couple of dumbbells, a kettlebell, a jump rope and a mat. Another positive is that you can do it anywhere – at home, while traveling, at the beach, in the pool… Anywhere!
(image credit to Greatist)
The thing I love most about HIIT is that it increases the metabolism rate, and the aging process is slowed down. Yey! Also, higher metabolism really works for me, as in the past I had episodes of hipotyroid, which
If you think of it, HIIT comes naturally. We all did it and sometimes still do it. 🙂 For instance, let’s think about the way we played while we were kids – We ran around the playground for a few seconds or even minutes, then stopping for a rest. Then we repeated it all over again. Seems like short bursts of high intensity activity is somehow hardwired into our DNA.
Who is HIIT for?
Let’s start with the untrained persons. Because most of you will be telling me – yeah, that’ pretty easy if your’re in a good shape and you exercise on a daily basis. If you are sedentary or exercise really little every once in a while, please check with your doctor first. This is really important, because otherwise you might put your own well being at risk by doing exercises that are way to high impact for your body.
When starting out, I highly recommend to work out at comfortable intensities, but the aim should be to slowly but steady increase the intensity to 90 % – 100% of your maximal heart rate.
What’s my maximal heart rate? This heart rate is something that you must calculate by yourself, based on your age. The formula is pretty simple:
maximal heart rate = 220 – (your age).
For instance, in my case, it’s 220 – 29 = 191. So my pulse should be around 190-191 while working out high intensity intervals.
For an untrained person, you should always start off at the easier end of difficulty, working your way up towards the maximal heart rate intensity. Also, you can increase the time of the recovery period to a recovery interval that’s enough for you to catch your breath and allow the pulse to go down around 65 % of the maximal heart rate:
recovery heart rare = maximal heart rate * 0.65.
You will be surprised to see that after only a couple of HIIT training sessions, you will be able to increase the intensity. But most of all, you’ll be surprised of how quickly your body adapted and how your fitness level has improved.
For trained persons, HIIT will give them the chance to reach their goals more quickly and push their limits a little bit further. I expect them to become instant HIIT fans. 🙂
The busy persons – this part is my favourite – HIIT allows you to achieve all the benefits of a longer training in a shorter time.
Why is HIIT training better for weight loss than constant interval training?
I have to admit I was really curious why and how I can lose so much weight by just working out 20-30 minutes / day, while in the past I spent months and months training (60 minutes / training session at least 3-4 times / week) without losing much weight nor gaining muscle definition as I would have expected.
Seems that there are two mechanisms that HIIT triggers inside our bodies:
#1 – HIIT training increases the exercise intensity, which leads to increased caloric expenditure (by a lot). So this means that when you work out and do HIIT, you’ll end up burning more calories (and lose weight), as the caloric expenditure grows exponentially.
#2 – It’s about the excess post exercise oxygen consumption, but you might have heard of it as the after burn effect. So how does this weird mechanism helps us lose weight after the workout is over / done / completed? I’ve read that while training really hard, during the high intensity interval, the aerobic system alone is not capable of supplying the required energy to complete the exercise. That’s when another system in our body (the anaerobic system) steps in and to assure the extra energy. While doing that, a large amount of lactic acid builds up in our muscles, as the exercising at the maximal heart rate. This elevated level of oxygen consumption will continue to have a training effect on the body. So ever if your workout is over, your body will continue to burn calories at a higher rate.
Pretty cool, right? You might ask me how long does the post workout burn effect lasts… Well, it depends on how hard you train – it can last from a couple of hours after the workout up until 48 hours.
But doesn’t lactic acid lead to muscle soreness? Doesn’t it build up in your muscles and make your muscles burn!? Well… It turns out, these are just myths. Lactic acid is actually a fuel, not a caustic waste product that will give you sore muscles. Muscles produce it from glucose on purpose, and they burn it to obtain energy.
Ok, but what makes the muscles feel sore? The answer is quite simple and also obvious: “[…] the swelling in the muscle compartment that results from an influx of white blood cells, and other nutrients and fluids that flow to the muscles to repair the “damage” after a tough workout. The type of muscle damage I am referring to is microscopic (it occurs in small protein contractile units of the muscle called myofibrils) and is part of the normal process of growth in the body called anabolism. It is not the type of damage or injury that you see your doctor about. The swelling and inflammation can build up for days after a workout, and that’s why muscle soreness may be worse two, three, or even four days after a workout.” [Muscle Soreness, Richard Weil, MEd, CDE]
While exersicing, the level of beta-endorphins increases a lot. This is the fell good molecule that makes us feel somehow euforic after a workout. It is actually our body’s response to pain. The more intense our workout is, the more beta-endorphins molecules are released, and the after workout feeling is better.
So now that I’ve give you a deeper dive in what HIIT actually is, how do you feel about it? Would you try it? Are you already HIITing it up?