You’ve likely heard about HIIT workouts before, but did you know there are actually a few types of HIIT workouts that each cater to a different training style? In this article, we’ll cover everything you need to know about HIIT workouts, the benefits, and the top 5 best types of HIIT workouts out there, designed to accelerate fat burning and help you build strong, beautiful muscles. Who knows, maybe you’ll find your new favorite workout style!
What Are HIIT Workouts?
HIIT is an acronym that stands for High-Intensity Interval Training. It involves repeated bursts of high-intensity exercise combined with low-intensity recovery periods. An exercise that is considered “high-intensity” brings your heart rate to about 80-90% of your maximum heart rate (MHR) for a short bout of time. This is also known as the anaerobic heart rate zone.
*For reference, you can calculate your maximum heart rate by subtracting the number 220 from your age.
220 - (age) = MHR
How does HIIT work?
When it comes to improving overall fitness and performance, your exercise should include two phases of effort: aerobic training and anaerobic training.
- Aerobic exercise—Aerobic exercise is when your heart rate is operating at 70-80% of your maximum heart rate and is considered low-intensity. This type of exercise requires the presence of oxygen in order to adequately meet energy demands. Aerobic exercise is beneficial for building cardiovascular endurance, improving heart health, and more. 
- Anaerobic exercise—Anaerobic exercise is any activity that puts your heart rate between 80-90% of your MHR. This type of exercise does not require oxygen so it’s imperative that you only exercise in this heart rate zone for not more than 2 minutes. The general idea is that a lot of energy will be released within a small period of time, therefore, burning more calories in less time.
Benefits of HIIT Workouts
With any physical exercise, there’s a slew of health benefits associated with it. Whether you’re running on the treadmill, playing with your kids, kayaking around your favorite lake, or even having sex, physical activities that keeps you moving are great for your body and your health! HIIT workouts, on the other hand, are especially great for those who want to lose body fat and build muscle in minimal time. If you’re thinking of adding HIIT workouts to your exercise routine, you’re in for a real treat! Here’s a brief summary of all the incredible health benefits associated with HIIT training:
- Accelerates fat loss—Blasting through body fat is what HIIT is all about! Studies show that HIIT exercise increases body fat reduction more than other forms of exercise. 
- Builds lean muscle—One of the reasons HIIT workouts are so effective at building muscle is because exercise at this intensity requires the body to use more muscle tissue in order to perform. A compelling study from the European Journal of Applied Physiology found that HIIT workouts require the body to use up to 80% of its muscle fibers compared to lower intensity exercise where only 20-40% of muscle fibers were used.  Similarly, other studies show that HIIT exercise can significantly influence muscle size in overweight individuals. 
- Boosts metabolism—Metabolism is how your body converts the nutrients you consume in your diet to ATP (adenosine triphosphate), the fuel your body needs to perform physical activity. HIIT exercise can increase your metabolism (and your production of ATP) due to a physiological effect called post-exercise oxygen consumption (EPOC). Also known as oxygen debt, EPOC is the amount of oxygen required to restore your body to its normal, resting level of metabolic function (called homeostasis). In other words, a higher metabolism allows you to burn more calories at rest. It also explains how your body can continue to burn calories long after you’ve finished your workout.
- Improves heart health—Research shows that bursts of high-intensity activity can equally improve the health of your heart and lungs in less time compared to 30 minutes of moderate-intensity exercise per day. 
- Burns more calories in less time—HIIT exercise has also been shown to increase your metabolism by using fat for energy, not carbohydrates. You see, fat is 9 calories per gram, whereas carbohydrates only contain 4 calories per gram. Calories are energy, and since HIIT exercise has a higher energy expenditure, your body uses fat calories to give it the immediate energy it needs to complete the exercise. Aside from this, you can burn 25-30% more calories in 30 minutes each of HIIT, compared to other forms of workouts.
Best HIIT Workouts To Transform Your Body & Health
Tabata is a type of HIIT exercise that was originally created in Japan by Dr.Izumi Tabata and a team of researchers from the National Institute of Fitness and Sports in Tokyo. The Tabata style training method has been proven to not only increase aerobic threshold (cardiovascular endurance) but increases the anaerobic threshold as well (muscular endurance). These quick workouts involved performing an exercise for 20 seconds at maximum intensity followed by a 10-second recovery period, and repeated 8 times. For example, a Tababa circuit for plyo lunges would be:
- 20 seconds plyo lunges (maximum effort)
- 10 seconds rest
- Repeat 8 times (total of sets)
Performing an exercise Every Minute On the Minute (EMOM) is a great way to keep your intensity during a workout. It’s performed with a timer that sounds every minute for a certain period of time. The concept is fairly simple but highly effective for fat loss. Here’s how to do it: You either have a single exercise or a short series of exercises to complete in a one-minute period. If you finish before the one minute timer, you can use that time as a rest period. For example:
If you have a 10 minute EMOM workout that says to complete 10 air squats, 10 pushups, and 10 sit ups, start by setting a timer to sound every minute for 10 minutes. At the start of the timer, complete the exercises. If you complete the exercises before the timer dings again, you rest. Once the timer dings, you begin again. So, every minute on the minute you complete the exercises until the 10 minutes are up.
AMRAP workouts are my personal favorite type of HIIT workout. It stands for As Many Rounds As Possible. The idea here is to complete as many rounds as possible of the exercises as fast as you can, resting when needed, and at your own pace. If we were the take the same workout from above (10 air squats, 10 pushups, and 10 sit ups) into a 10 minute AMRAP, the only difference is that you would complete the exercises continuously with as little rest as possible. With an EMOM, you are capping the number of sets at however long your EMOM is. With AMRAP, you complete however many sets (rounds) of that exercise as you can within the allotted time. So, you could essentially complete more than 10 rounds depending on how fast you’re moving. This is a great option for anyone who loves competition!
4. Interval Training
Generally speaking, all of the above exercises are a form of interval training. However, standard interval training, also known as circuit training, is simply a framework for completing 2-3 exercises back-to-back, with no rest in between them, but a recovery period at the end of the interval. Interval training is a great format for people looking to get the effects of HIIT training even with simple, compound lifts often performed in bodybuilding.
5. GS 30 / 60
GS 30 and GS 60 are two of the four workout programs found in Grown Strong Fitness. Both programs were created to give you the flexibility you need to reach your goals no matter what your lifestyle is like. And what’s better, is that both programs include all 4 of the best HIIT workout styles for burning fat and building muscle in every workout! GS 30 is a full body HIIT workout designed for people who are short on time or may have limited equipment who are looking to get maximum results in as little time as possible, whereas GS 60 combines the best of HIIT training and bodybuilding with functional training. Both programs are effective for fat loss and muscle building but vary depending on the time and equipment available to you. There’s even a step-by-step tutorial video for each exercise that appears in the programs every single day. So, you’ll always begin your workout with the confidence and support you need to perform your best.
As a Grown Strong Fitness member, you also gain access to GS 60+ which is an accelerated program for those looking to increase strength and gain a competitive edge in their training. The GS 20, 30, 60, and 60+ workouts allows you to jump between programs so no matter if you only have time for a quick 30 minute workout, or you have an entire afternoon to focus on your workout, Grown Strong Fitness is designed to fit your ever-changing lifestyle. There are a ton of other perks for being a Grown Strong Fitness member outside of getting amazing results! To learn more about the programs or to try it for 7-days COMPLETELY FREE, click here.