If you've read anything fitness, you've probably heard that high-intensity interval training has many benefits.
You know that it can be as beneficial as a longer, traditional workout. You probably know that it helps you lose weight and increases your athletic performance, too.
Related - 8 HIIT Workouts to Get You Shredded
What you didn't know is that many classes that claim they are high-intensity are more moderately-intense. This means that many of your HIIT classes aren't actually high-intensity.
So What Is High-Intensity Interval Training?
In its most basic definition, high-intensity interval training is a workout that alternates between periods of intense bursts of activity and fixed periods of less-intense activity.
Basically, go for a moderate speed walk. Sprint and run as fast as you can, similar to if you were running from trouble for 30 seconds. After the running, walk at a leisurely pace for 60 seconds to cool down. Repeat this interval as long as you can, or up to 15 minutes.
It sounds simple, and it is.
There is one caveat about HIIT training - you have to push yourself hard.
90% Capacity or More
If you want to get technical with your definition, HIIT alternates between a block of 90%-100% of your VO2max - This is all-out, everything you got. The other block is typically in the 50% VO2max range.
While both your work output and recovery intervals will be different to someone else due to overall health and athletic performance, there are two types of high-intensity interval training that most do.
1.) Submaximal rates that are below your VO2max tend to have longer work intervals and a larger work to rest ration. So for easy numbers, for every 5 seconds, you spend in the high-intensity block, you'll have 1 second of rest. So a 30-second high-intensity section with a 6-second low-intensity recovery session is normal.
2.) If you plan on going near or above your VO2max, you will have shorter work intervals with a smaller work to rest ratio. So 30 seconds of all-out "do or die" intensity can be accompanied with a 2.5 minute rest period. You will look for a 1:5 work to rest ratio.
Basically, the higher your intensity levels, the longer you can rest between. Keep your heart rate elevated and push hard.
Your Favorite Classes Aren’t What They Say
For many, these "high-intensity interval training" classes are not working at a 90% or higher capacity. For it to be truly high-intensity, you literally go into an anaerobic threshold - tapping into that energy system.
What Is the Anaerobic Threshold?
The anaerobic threshold refers to a point in your training where lactic acid starts to build up in the muscles. This will not happen in a HIIT workout unless you are working at 90% capacity.
These 45-minute "HIIT" workouts that your gym promotes are not actually high-intensity. You just cannot keep up that level of intense work for that long.
You're basically doing a cardio class.
Please note, there's nothing wrong with this. You're just not actually doing a HIIT workout.
Consistency is Key
One great workout doesn't change your life. Ultimate, you need to consistently workout - pushing yourself to do more every time.
That's how you build muscle, burn body fat, and get more athletic.
Eating one salad throughout your crap diet doesn't make you healthy either. While that one pizza you just smashed didn't immediately make you gain weight, the consistent act of overeating will make you overweight.
It's all about consistently improving your health. One step at a time. Literally.
8 Benefits of Actual High-Intensity Interval Training
#1 - It's Efficient
If you don't have much time to workout, HIIT workouts are great.
You can squeeze in a workout during your lunch or make a quick stop on your way home from work.
You can achieve measurable progress in a short 15-minute workout, done three times per week. Just think, you are able to get the same benefits (if not more) than the people who sludge along on the treadmill for hours.
A 2011 study shows that only 2 weeks of high-intensity interval training will improve your aerobic capacity as much as 6 to 8 weeks of endurance training would.
Hell, you can bust through a solid Tabata workout in just 4 minutes.
#2 - You Will Burn More Fat
The effect of 90% work puts your body into a repair cycle overdrive.
That means you stay burning calories roughly 24 hours after your HIIT workout.
#3 - Your Heart Will Thank You
Most people get winded simply walking up some stairs or walking to go get the mail.
Many people aren't used to pushing themselves to that level of anaerobic work, but the extreme training produces extreme results.
A 2006 study found that after 8 weeks of HIIT workouts, subjects could bicycle twice as long as they could, maintaining the same pace.
#4 - You Don’t Really Have to Have Equipment
HIIT workouts can be in many forms.
Running, biking, jump roping, and rowing are all great for HIIT. You don't need any equipment, and you can do the workout anywhere.
#5 - You Will Maintain and Build Muscle
It's not a secret that you can burn muscle and remain fat - all while losing weight.
Studies show steady state cardio encourages muscle loss. This is bad.
HIIT workouts get the most out of your body without sacrificing your muscles for fuel. This is why it is important to reach a 90% or higher threshold.
#6 - Your Metabolism Will Be Boosted
High-intensity training stimulates the production of human growth hormone by up to 450% during the 24-hour period post-workout.
Human growth hormone is responsible for burning more calories and slowing the aging process.
#7 - You Can Do It Anywhere
Anywhere you have enough room to move is enough room for a HIIT workout.
Simply train at max effort for a short period of time and take a rest.
It's not a hard concept - you just have to push yourself.
#8 - Your Mental Fortitude Will Be Tested
Pushing yourself past the level that you thought you could perform at is hard. This isn't something that you will be able to chat it up with your friend.
If you can, you're not doing it right.
You're going to feel pain, burning, and you will be sucking wind like you are close to death - but you won't be bored.
There are plenty of studies out there that outline the benefits of high-intensity interval training.
If you don't believe me, read up more on them and make your decision.
Do you have the mental fortitude to push yourself beyond your breaking point? I bet you have more in the tank than you give yourself credit for.