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What is HIIT?

High Intensity Interval Training (HIIT)

If you have been around me very long you have realized that I am a huge fan of High-Intensity Interval Training (HIIT). I have been training this way for the vast majority of my life.  I am excited to present the information and research below that substantiates what I have found to be true and explains some of the reasons why our fitness programs are so effective for the vast majority of people. So, whether you want to loose fat mass, gain muscle mass or improve performance with minimal risk of injury our HIIT program is for you.

The American Council on Exercise released an article regarding HIIT. Simply put, HIIT involves repeated bouts of high-intensity (> 70% MAXHR) effort interspersed with recovery. According to ACE, HIIT improves both metabolic function, cardiorespiratory fitness, and requires considerably less workout time.

However, keep in mind that ACE is speaking very broadly with regard to HIIT. Not all HIIT is the same and may not offer the same positive results. In some cases it may result in negative results if not done properly. The results depend on the coach, the workout and each individuals specific set of circumstances and goals.

Research indicates you can gain as much muscle lifting loads as you can lifting heavy loads as long as you go to failure. The awesome thing is the lighter loads are easier on you joints, burn more calories and fat.

According to ACE, here’s what the research says about why HIIT is such an effective workout…

HIIT challenges the body to perform at the upper end of the aerobic training zone, which is called the second lactate threshold. When training at this end of the aerobic training zone, there is shift from using aerobic metabolism to anaerobic metabolism to produce energy to fuel the activity.  Training at this intensity improves cardio respiratory function during exercise and at rest, and the body shifts from using aerobic metabolism to anaerobic mechanism to produce energy and generate force. In fact, HIIT training has been shown to benefit just about everyone, from endurance and strength athletes to recreational exercisers. That’s because it’s adaptable, meaning it can be used for aerobic training as well as muscular strength training, or a combination of the two.

HIIT also increases caloric burn AFTER an exercise bout through a process known as excess post-exercise oxygen consumption, or EPOC. Essentially, the body must consume more oxygen, which increases the amount of calories that are being burned, to return to its pre-exercising state after an intense bout of exercise. Some studies have shown than metabolism is increased 1.2x the normal rate for up to four hours after HIIT. Therefore, by incorporating HIIT training into a workout regiment, body composition may improve as a result of the greater caloric burn associated with HIIT training. However, it is important to note that body composition is not altered by exercise alone; nutrition plays a key role in optimizing one’s fat-mass-to-lean-mass ratio.

When it comes to workout efficiency, HIIT is especially attractive in that it does not require a large amount of time to reap the benefits. HIIT workouts typically last 20-30 minutes and are extremely effective as long as the intensity level is high. From both a psychological and physiological perspective, it is easier to maintain a high level intensity for a brief period of time than it is over a longer period of time, greater than 30 minutes. With a growing body of research demonstrating that HIIT is an effective and efficient way to exercise, HIIT is here to stay!

Many people enjoy running! It allows you to get a stress-reducing, endurance-boosting workout with just a pair of shoes and an open road.

Of course, running also burns calories. At a 10-minute-per-mile pace—roughly the average guy’s marathon pace—you’ll fry about 10 calories a minute.

That’s a solid number, and if you run faster, you can burn even more. However, running doesn’t do anything to help build lean muscle mass. So, if running isn’t your favorite cardio activity or if you goal is to build lean muscle mass, HIIT done properly with progressive overload to failure will help you torch calories and fat at a lightning fast rate and build the lean muscle mass you desire.

Quite simply you burn calories more efficiently doing HIIT workouts than you do running. Most people don’t realize this, though. That’s often because the number of calories you’re told you just burned is typically estimated from the Compendium of Physical Activities, which calculates energy expended through aerobic metabolism. That works well for low- to medium-intensity exercise, but not so well for higher-intensity activities that rely on both aerobic and anaerobic metabolism.

According to an article written by Men’s Health, when researchers at the University of Southern Maine used a more advanced method to estimate energy expenditure during exercise, they found that weight training burns up to 71 percent more calories than originally thought. Which suggests that a fast-paced circuit workout burns at least as many calories as running at a 6-minute per mile pace.  If you increase the intensity, use the right types of exercises, intervals and sequence you burn even more such as the 346 calorie 13 minute HIIT workout shown below.

All HIIT workouts do not yield the same results. It is important that coaches or participants have the proper training and background to safely and effectively get the most out of the HIIT workout based on each individuals unique goals. Understanding the changes and adaptations that occur as a result of the particular exercises, frequencies, sequences, intensity, duration and load are important when developing programs or circuits. Men’s Health wrote an article on a very specific type of HIIT workout further substantiating the caloric burn, muscle building effects and efficiency of HIIT done properly. They explained, a routine detailed in new research from North Dakota State University is one of the most efficient calorie cookers they’ve ever seen.

The Men’s Health article details a recent HIIT study, with participants performing 6 different exercises, using 50 percent of their one-rep max, while completing as many reps of the exercise as they could bang out in 30 seconds, then resting for 15 seconds and completing a total of 3 rounds. According to the research, which was presented to the American College of Sports Medicine (ACSM) Annual Meeting in Boston, Massachusetts, the study participants incinerated an average of 346 calories (26.6 calories a minute) in just 13 minutes. It’s the equivalent intensity to running a 5-minute mile pace (12mph) non-stop for 13 minutes.

Comparatively speaking, individuals of the same size and fitness level running at a 10-minute mile pace (6mph) for the same amount of time, only burns 146 calories, according to California State University research. Also, according to scientists at Kennesaw State University people completing CrossFit’s notorious Cindy workout, burn 261 calories but take 20 minutes (13 calories a minute) to complete the workout. The Cindy workout is completed by doing 5 pullups, 10 pushups, and 15 air squats as many rounds as possible in 20 minutes. Neither of these modes of exercise come close to the 346 calorie workout as far as caloric burn and muscle building potential per amount of time spent working out.

Now to detail out the 346 calorie scorcher. Participants followed the 50 percent, 30 seconds work, 15 second rest protocol for three sets of six different weight-lifting exercises, including bench press, bent rows, tricep extensions, bicep curs, leg extensions and hamstring curls for a total of 3 rounds. Participants doing similar work and exercises with longer rests and heavier weights actually burned 51 less calories.

Those results suggest that there’s something about the super-short, 15-second rests that leads to an astronomical calorie burn, says study author Jake Erickson, a graduate assistant at North Dakota State University. You use up more energy—a.k.a. calories—when you give your body less time to recover between bouts of intense effort.

Also, when just considering volume of weight moved far more calories are used to perform an exercise of 50 percent of your max say 20 times that it does to perform your max 1 time. For example, dead-lifting 100 pounds 20 times (2,000 pounds of work) burns far more calories than dead-lifting 200 pounds 1 time.

Research indicates you can gain as much muscle lifting loads as you can lifting heavy loads as long as you go to failure. The awesome thing is the lighter loads are easier on you joints and burn more calories and fat. Even though participants do not use heavy loads in their usual workouts their muscular strength and endurance increase as well as their overall performance. In addition our T2 program performs maximum exertion activities to determine their maximum output using heavier loads.

Here are some other fantastic and easy to implement HIIT workouts that are sure to ignite your caloric burn.

Kettle bell Swings – This explosive cardio exercise works the big, powerful muscles around your glutes and quads, and sends your heart into overdrive, according to research from the University of Wisconsin. In the study, participants burned 20.2 calories a minute and their average heart was 93 percent of its max for the course of a 20-minute workout.

Indoor Rowing – A 185-pound guy can burn 377 calories during 30 minutes of vigorous rowing, or about 12.5 calorie per minute, reports a Harvard University study. And because you need to utilize the muscles in your arms, legs, and back for efficient strokes, it’s a great total-body trainer.

The Burpee – A 180-pound person burns about 1.43 calories per burpee, says exercise scientist and Spartan Coach Jeff Godin. So if you can hammer out at least seven a minute you’re in the double digits.

But you should shoot to average at least 10 every 60 seconds, or a rate of 14.3 calories per minute. Why? Performing just 10 reps at a fast pace can rev your metabolism as much as a 30-second, all-out bike sprint, according to a study presented at the American College of Sports Medicine annual meeting, and that makes the burpee a killer cardio exercise.

AirDyne Bike Sprints – It sounds downright crazy, but Gym Jones manager Rob MacDonald proved that it’s possible to blast 87 calories in one minute on this stationary bike that increases its resistance as you pedal harder. The key is to give everything you have in that 60 seconds.

Note: This was by no means a scientific experiment, and relies on the accuracy of the built-in AirDyne monitor, which calculates calories by converting revolutions of the fan into physical work.

Jumping Rope – Moderate-intensity rope jumping—about 100 to 120 skips per minute—burns about 13 calories a minute, according to the Compendium of Physical Activities.

This cardio exercise uses more muscle groups than jogging, and challenges your balance and coordination—especially if you practice drills that require extra hand and foot skills.

“Cindy” – This CrossFit Workout of the Day (WOD) burns an average 13 calories per minute, according to scientists at Kennesaw State University.

It’s effective because it pairs three exercises—5 pullups, 10 pushups, and 15 air squats—that work different major muscle groups, and you do as many rounds as possible in 20 minutes.

So if you’re in amazing condition, you can go all-out for each one, without slowing down or stopping to recover in between.

If you’re somewhat less than amazing (like most people), you simply rest when needed. For example, you don’t move on to the push up until you’ve completed 5 reps of the pull up, even if you have to stop and start.

Tabata Jump Squats – This four-minute miracle drill burns major calories both during a workout and after. In an Auburn University at Montgomery study, participants who did eight rounds of all-out jump squats—20 seconds of hard work, separated by 10 seconds of rest—burned 13.4 calories per minute and doubled their post-exercise metabolic rate for at least 30 minutes.

If you are interested in HIIT training but just not sure where to start or you are looking for a program that is safe and appropriate yet challenging for all levels of fitness then check out our popular HIIT Transformation Program. The HIIT Transformation Program utilizes a very similar HIIT protocol to the one presented to the ACSM that incinerated 346 calories in 13 minutes, cranks up your post exercise caloric burn via EPOC, boasts incredible strength gains, improves performance, improves lean body mass, destroys fat mass and significantly improves cardio respiratory function.

Go Hard or Go Home! Just HIIT IT!

Coach Tim Garrett