Pros & Cons of HIIT (High-Intensity Interval Training) Explained

HIIT or high-intensity interval training can be described in three words:

fast
explosive
and efficient.

This workout style has become a popular option because it usually requires no equipment and is a time-efficient way to get an intense workout.

If you have browsed Youtube looking for workouts, you have most likely stumbled upon hundreds of different HIIT workouts — in fact, most at-home workouts are HIIT based.

From beginner’s workouts that are only 10-minutes long to brutal 45-minute sessions, there is an option for anyone.

But is HIIT actually for everyone? What are the pros and cons of HIIT workouts?

A few of the pros or benefits of HIIT include its effectiveness and efficiency. It burns a lot of calories quickly, while increasing your endurance, cardiovascular conditioning, and strength.

HIIT is a great option for weight loss and general fitness.

However, HIIT is high impact and high intensity, which can lead to injuries — it can also lead to overuse or recovery problems if beginners aren’t working in enough rest.

I spoke with fitness professionals and personal trainers about the pros and cons of HIIT for beginners to get the inside scoop.

Pros of HIIT

First up, there’s a lot to like about HIIT, or High Intensity Interval Training.

After all, it’s popular for a reason!

1. Great for Weight Loss

When most people choose to do a HIIT workout, they are most likely thinking about the weight loss benefits.

These workouts are incredibly tough, even when they’re short, and they’ll help you burn a lot of calories.

When I spoke with NSCA-certified personal trainer David Rosales about the fat loss benefits of HIIT, he said:

“We know how amazing HIIT (high-intensity interval training) is for fat loss. A review of a whole bunch of studies (768 to be exact) found that HIIT participants lost 28.5% more fat than moderate-intensity training counterparts.”

If one of your main fitness goals is shedding some excess pounds, HIIT is a time-efficient way to get a quick fat-burning workout.

Following your HIIT workout, you will also experience something known as the “afterburn effect.”

After finishing the challenging workout, your body’s calorie-burning will stay elevated while the body recovers and restores itself.

This natural response will help your body burn fat longer and help you stay in that all-important calorie deficit for weight loss.

(Just remember, you won’t lose weight doing HIIT without cleaning up your diet or at least keeping it in check.)

2. The Workouts are Short

Joe Johnson of 9-to-5Nutrition.com had this to say about the pros and cons of HIIT:

“(HIIT) allows you to burn lots of calories in a short period of time. This means HIIT workouts are great even if you’ve only got 15-20 minutes a day to work out.”

If you find yourself running low on time, HIIT workouts are the perfect choice to cut down the necessary time investment to see results.

Many busy people have trouble sticking to a workout regime because most workouts take 45-minutes to 1-hour.

With HIIT, you can get an incredibly efficient workout in only 10-minutes when done correctly.

You must push yourself with intensity, but once the workout is over—you will see HIIT results and feel the same exhaustion of a class 3x the length.

Some HIIT classes (especially at gyms and fitness studios) are 45 minutes to an hour in length, but you can accomplish almost as much in a 15 minute window at high intensity levels.

3. Improves Heart & Lung Health

Heart and lung health are a vital piece of your overall fitness.

Joe Johnson stressed the importance of HIIT for heart health by saying,

“HIIT is great for heart and lung health. The heart is a muscle just like any other and needs to be trained for optimal efficiency.”

If you’e an athlete, HIIT will improve your performance by increasing your overall endurance and cardiovascular conditioning.

If you are not an athlete, HIIT will also help to improve your resting heart rate and reduce your blood pressure.

Your resting heart rate should be between 60-100 beats per minute as a frame of reference.

If you are an athlete with above-average heart health, your resting heart rate can be as low as 40 beats per minute.

4. Builds Functional Strength & Muscle

One of the core principles of a HIIT workout is using calisthenics movements that build strength and muscle.

These movements are extremely challenging, especially done with little rest, and you will soon notice your overall strength increasing.

Some examples of exercises you will find in your typical HIIT workout are:

Squats
Push-ups
Lunges
Planks
Burpees

In some cases, you can even bring weights into the workout and do movements with dumbbells.

These workouts are more advanced, but once you build-up to that level—you will always have a challenging workout.

For a technical benefit of HIIT workouts, I spoke with Dr. Len Lopez about this fitness style’s muscle-building benefits.

For those looking to build muscle, Lopez noted that HIIT workouts are:

“High Intensity….and that’s what’s going to release the greatest spike of Testosterone (TT) and (GH)…..so you can add and keep lean muscle and burn fat.”

(Learn more about the different types of HIIT here.)

5. It Can Be Done Anywhere

From a hotel room to the beach, you can do a HIIT workout pretty much anywhere.

There is no equipment required to do most HIIT workouts, and it’s extremely easy to find free workouts to follow on YouTube.

While home workouts can be efficient and convenient, you can elevate your workouts by attending HIIT classes as well.

The social aspect of these classes improves the experience, and you can be more motivated to attend the classes.

You will often hear HIIT workouts be described as “boot camp” workouts where you will workout with a group through an intense workout.

Joe Johnson mentioned this often overlooked aspect of HIIT by saying:

“HIIT can be social, particularly if you do boot camps or group sessions. It’s a great way to meet with your friends, meaning it has mental health benefits.”

Cons of HIIT

HIIT has a ton of health, fitness, and convenience benefits.

But it also has some drawbacks, as well, so it’s not for everyone.

1. Higher Risk of Injury

Unlike low-impact exercises like swimming or cycling, HIIT workouts are considered high-impact exercise.

Exercises like burpees or jumping jacks can be painful for those who suffer from chronic pain.

Trainers are also aware of this high-impact and will advise the elderly and beginners to avoid these workouts.

Personal trainer Daniel Dublin noted the high-impact nature of HIIT workouts when he said:

“Watch out for injuries as HIIT training is a lot more demanding and challenging by its very nature, pushing the body to its physical limits.”

“The increased pressure can lead to increased risk of injury compared to lighter forms of exercise, particularly those who aren’t physically active and are new to exercise.”

Along with its high-impact nature, proper form often takes a backseat to tempo and intensity — which can lead to injuries.

2. Can Be Hard to Stay Motivated

While this con depends on each person, HIIT workouts can be challenging to stick to consistently.

Personal trainer Daniel Dublin laid out the realistic expectations of attending a HIIT class by saying:

“Do you enjoy sprinting as hard as you can, even if it’s just for 30 seconds? While the benefits sound appealing, many people don’t enjoy it or don’t have the resolve to push themselves that hard.”

Many beginners get caught up in all of the fantastic benefits of HIIT, not thinking about how hard these workouts actually are.

The classes are short and efficient, but you will be pushing your body to its physical limits during that time.

For those who are new to fitness, this could create a bad relationship with exercise, especially if they start to dread the workouts.

Fitness instructor Joe Johnson brought up the often overlooked aspect of mental energy when he said:

“HIIT workouts can be difficult. They take a lot of mental energy and willpower to psych yourself up for, especially if they mean training outside in the winter, which means they are easy to skip.”

To help you get and stay motivated for your next HIIT workout, read my Ultimate HIIT Motivation to light a spark of motivation to take on your next workout.

3. Requires Longer Recovery Times

HIIT workouts are high-intensity workouts that will push both your muscles and cardiovascular endurance to their limits.

Trainer David Rosales noted that the effects of these workouts on your body, saying:

“Anything done at a truly high intensity is incredibly taxing—both on the specific muscles and energy system involved, but also on the nervous system as a whole.”

If you are very new to the fitness world, any workout you do will require you to focus on recovery.

This recovery is even more critical with HIIT because of the impacts it has on your body.

It is very easy to burn yourself out if you decide to do HIIT workouts more than three times per week when you are starting out.

Your body will not have adequate recovery time before you do another workout.

4. Overwhelming for Beginners

If you have a short history of exercising, many personal trainers will advise you to try something less intense to start.

HIIT workouts are challenging for even the most experienced fitness enthusiasts, so it’s easy to get discouraged.

Rosales shared a research study relating to trainees on a HIIT program to prove this point.

“A 2018 study found general population trainees (this isn’t even necessarily beginners) were less likely to adhere to a HIIT program if left unsupervised than a moderate or low-intensity cardio program.

“In other words, the high-intensity can dissuade a beginner from sticking to a program.”

While HIIT programs are great for getting results quickly, they shouldn’t be your only form of exercise.

It’s easy to be overwhelmed and discouraged when trying to follow a program that consists of HIIT workouts and nothing else.

Try to mix in both high-intensity workouts and other low-intensity forms of exercise like:

swimming
walking or jogging
low-impact cycling

Getting some “easy wins” under your belt will keep your confidence and motivation higher in the long run.

5. Drastically Increases Appetite

If one of your goals is to lose weight, HIIT workouts can be great because they burn a lot of calories.

But if you’re not careful, they can work against you.

Intense workouts like HIIT can work up an appetite as your body wants to increase its calories to aid recovery.

Joe Johnson mentioned the effects on your appetite that HIIT workouts will have, creating a conflicting relationship.

“HIIT workouts can really make you work up an appetite – if you’re trying to lose weight, this may not be such a great thing .

“It’s very easy to consume back all the calories you just burned in your workout!”

It’s a common feeling to want to eat a massive meal after attending a HIIT workout, but it’s essential to replace these meals with those that align with your weight loss goals.

If you struggle to stay full and fulfilled while following a HIIT program, you might want to consider burning calories with walking or other lower intensity options to keep your appetite down.

Wrapping Up

HIIT workouts are one of the most intense and effective forms of exercise around.

This short but efficient fitness style will push your body to its limits within only 15-20 minutes.

These workouts are great for weight loss, building muscle, and improving your cardiovascular health.

However, setting realistic expectations and giving yourself plenty of recovery time is vital for these workouts.

The workouts are tough, and they can put a lot of strain on your body if you are a beginner. There’s also an injury risk if you’re not careful about managing your technique.

Not sure if HIIT is for you? Check out more on the:

Hope this helps!