What’s HIIT Cardio?^2,4

What’s up party people, welcome back (all probably like one of you) for this blog! You know what, if my blogs help even one person or gives someone some form of entertainment, that’s ok. Maybe that one person will always be me, but that’s ok too!

Anyways, lets talk about HIIT cardio? What’s HIIT cardio? Is it when you hit something while doing cardio? No! It’s an acronym for “high intensity interval training”. It’s when you push as hard as you can for a certain period of time followed by an interval of pushing at a moderate intensity. To put it in cardio terms, it’s like pedaling as fast on the elliptical you can for 1 minute and then pedaling at moderate pace for 2 minutes. You do this for a number of intervals, maybe like 7 or 8 times. Start off with less intervals and increase over time.

To calculate your maximal heart rate, you subtract your age from 220. Your heart rate should be 70-85% of your maximal heart rate for vigorous activity, as recommend by the American Heart Association. When I used to do HIIT, I personally didn’t monitor this, I just pushed as hard as I could.

Here’s an example to calculate your maximal heart rate. For someone who is 30 years of age:

• Maximal heart rate: 220 – 30 = 190
• Lower end of target heart rate: 190 multiplied by 0.7 = 133
• Higher end of target hear rate: 190 multiplied by 0.85 = 162

HIIT is great for people who might be short on time and need to get in their cardio in as short duration of time, possibly 20 or 30 minutes. This is different as opposed to LISS (low intensity steady state cardio) which will need to be performed for a longer period of time at a constant moderate pace. Check out my previous blog on LISS for more information on that: https://fitnessfinancetravel.com/low-intensity-steady-state-cardio/

Due to the fact that you are pushing yourself more, HIIT dose burn more calories (if performed correctly) during the time you do it as compared to LISS.

Before Jumping to All The Science

Before I dive into everything I read about, which was quite a bit, I just wanted to talk about a caloric deficit. No matter what you do, as long as you’re in a caloric deficit, you’ll lose weight. Simple as that. That’s as simple as you can keep it. You don’t even have to know the rest, but you can read it if you’re interested. There is a lot of discussion between HIIT and LISS, but if you aren’t controlling your diet, you still won’t lose weight. In my humble opinion and from what I do, I just do LISS as of right now. Maybe in the future I’ll start to do some HIIT as well if I get bored of LISS.

How Many Times A Week Should You Do HIIT

It’s different for everyone depending on how fast you can recover. It’s generally a lot more taxing on your body as opposed to LISS which you can do every day. That being said, HIIT cardio should only be performed 2-3 times a week for 20-30 minutes sessions. This is so you can recover properly and decrease the chances of experiencing injuries. If you can do more than that and enjoy doing it, then you can try for longer periods of time or more frequently. Or you can perform LISS on the other days of the week.

Comparing HIIT and LISS^{1,2,3,5,6,7,8,9,10,11}

So you might be thinking at this time, HIIT burns more calories, it much be better, not exactly though. HIIT does burns more calories while you’re doing it. At what cost though? It takes more time to recover from and it’s much tougher. It’s more mentally exhausting too, I can tell you that I personally dread it way more than LISS cardio. I only do LISS cardio to this point in time.

All but one of the studies I found stated that there was not difference in fat loss between HIIT and LISS. The only study that found a statistically significant difference difference was as study by Viana, this was in favor of HIIT cardio. Even then, the difference was a 6.2% in terms of body fat reduction for the HIIT group vs the 6% for the LISS group (0.2% difference).

A lot of people argue about the EPOC effect of HIIT cardio as well. What’s EPOC? Great question, it’s “excess post-exercise oxygen consumption”. Yeah, a mouthful I know (keep your mind out of the gutter).

With HIIT cardio your body isn’t getting enough oxygen replacement as you’re using a lot because you’re pushing so hard during the workout to regenerate ATP (that’s energy for your body). So after you’re done, your body burns more calories to replace the oxygen. You’ll basically be breathing harder even after performing HIIT as opposed to LISS. However, it’s basically an insignificant amount of calories. With LISS your body can replace more oxygen during the exercise as your body isn’t consuming as much after the workout.

From the studies I have read, it appears as if the EPOC effect is variable between people, the intervals they are performing and how long they do HIIT cardio for. It can last from under an hour to almost a day. It only makes a difference when people perform HIIT for prolonged period of time (most likely well over an hour). Let me tell you, that would be tough for most people who aren’t athletes.

When I did HIIT cardio, after I did my intense interval, my moderate intervals would turn into me barely being able to peddle on the elliptical. So I feel like it basically evened out for me as if I was doing LISS in terms of calories burned most likely. That’s why I just choose to do LISS as of now.

Benefits of HIIT^{1,2, 5}

HIIT is more time effective, you can burn the same amount of calories as LISS, but in a shorter period of time. So it’s time more efficient in terms of time spend doing cardio.

You can also increase your ability to sustain higher heart rates for a longer period of time and increasing your maximum heart rate. You can couple this with LISS so you can perform it at a higher rate to burn more calories.

What Are Some Disadvantages of HIIT? ^{1,2,3,5,6,7,8}

You’ll have to push very hard and will be putting a lot more stress on your joints while performing it which is a downside. This could lead to injury. Also, it was much more mentally fatiguing for me. I’d dread it every day. It’s tough.

How Long Will It Take to lose 10 Pounds With HIIT?

This is a commonly asked question. It all depends. For starters, you should only be aiming to lose 0.5-1% of your total body weight per week. Don’t rush it and destroy your metabolism. Your body is very smart, if you drop your calories too low, your body will adjust to your new maintenance eventually. If you want to lose more weight after that, you’ll have to drop even more calories. Take it slow. This will differ per person.

How long does it take to burn 500 calories with HIIT?

Once again, this all depends on you. How hard are you pushing and for how long. This will differ from person to person.

How Soon Can You See Results from HIIT?

This all depends on you. How hard are you pushing and for how long. This will differ from person to person. (sound familiar)

Is it better to do shorter or longer intervals in HIIT?

This depends on your capabilities. Usually, intense intervals can last up to a minute or two. I’ve personally never done more than a minute. I’ve always done HIIT on an elliptical and here’s the intervals I’ve used (remember to warm put 5-10 minutes before starting your intervals at a steady state before doing these and consider a 5-10 minutes cool down after):

• 15-20 seconds pushing as hard as I can followed by 45-40 seconds of a moderate pace. Keep this going until 20-30 minutes have elapsed.
• 30 seconds pushing as hard as I can followed by 30 seconds of a moderate pace. Keep this going until 20-30 minutes have elapsed.
• 1 minutes of pushing as hard as I can followed by 2 minutes of a moderate pace. Keep this up until 20-30 minutes have elapsed. To a point in my life, I was doing this this 5 days a week and worked up to 50 minutes. Looking back now, I’m not sure if it was even worth it. By the end of the session, my “pushing hard interval” was barely me barely pushing at all and trying not to pass out. Don’t be stupid like I was.

You could do this on stationary bike or maybe sprint outside. You could find HIIT workouts on YouTube as well.

Conclusion

HIIT is for people who want to burn more calories and are strained for time. It definitely should not be done every day and should only last 20-30 minutes to start off with. You can build stamina and work your way up if that’s what you want to do. There is an increased chance of injury as you are putting more strain on your joints and muscles.

Disclaimer: I’m not your doctor. Please consult your doctor, nutritionist or any health care professional before making any changes in your own lifestyle. These blogs are just me sharing my knowledge for you reading entertainment purpose only. None of this is medical advice.

 

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