H.I.I.T. TRAINING: Really a M.I.S.S.
One of the most overhyped exercise programs in my 35 years in the health and fitness industry is HIIT. As a reminder, HIIT stands for High-Intensity Interval Training and it is probably the most powerful marketing and misused acronym we have ever seen. Not only has it been used by health clubs to name and market workout programs, but a whole new fitness product model was created and thrived because of it. However, it's important to know it's not some magical new form of exercise.
Before I get into the theory behind the title of this article, I have to explain the truth about HIIT. First, it is nothing new; it has been around for years. Yet no club anywhere in the country (unless it has a sports performance center) is actually doing HIIT. HIIT is a form of interval training that was designed specifically to train athletes and enhance their performance levels. It is a very scientific form of training and is extremely intense. Most non-athletes would not make it through about 5 minutes of real HIIT. And if they tried they would either pass out or just crawl towards the exit door. A HIIT workout is designed by a team's strength and conditioning coach specifically to focus on some element of the athlete's athletic performance, like their speed. The intervals are specific in the amount of time, intensity, and exactly what movements and activity is done during those intervals. So while HIIT is a form of interval training, it is not what is done in clubs or studios.
However, what we do see in clubs and studios is just about every version of interval training that exists (and there are several). The workout is usually designed by the instructor with their specific customer base in mind. First, let me explain interval training to understand how it is different than HIIT. With HIIT, the intervals are designed very specifically with a very specific intent. With interval training, the design is much simpler. The instructor will usually design a circuit of exercises designed to increase the heart rate to what they expect will be a moderate intensity level for a certain period of time, and then allow for a recovery (rest) period before starting the next higher intensity interval. The intervals and exercises can be anything. Interval training is used with the intent of giving the individual a more intense workout than normal without completely wearing them out.
This is where HIIT becomes MISS. MISS is actually another acronym used for the type of interval training done by most clubs. It stands for "Moderate Interval Steady-State" training. To put this in layman's terms, when you are an athlete doing a HIIT workout there is no downtime. You are being pushed 100% the whole time. Think about a minute's worth of sprints with 15 seconds of active recovery, then back to a minute of sprints with the coach screaming at you to give 100% the whole time for the entire workout. In MISS, you are working at your own pace (which is usually not 100%), hence the "M" for moderate effort. Then, when you get into the intense interval, you end up going at your own pace because again, you work at the intensity you choose and try to hold it for the length of the intensity interval. Put all of these together and what you get is a "Moderate Intensity Steady State" interval workout.
Ok. So what is the issue? Issue Number 1: HIIT is not some magical workout. The marketing of it has lead people to believe that just by doing something called “HIIT,” something magical will happen. Again, it is not HIIT and there is nothing special about it above any other type of cardio exercise. Issue Number 2: As with any non-athlete interval training, most people are not working as hard as they think they are and in most cases not for the whole length of the workout. I will prove it with real data below. When you do any type of interval training, the tendency of almost everyone is while they are fresh they push really hard at the beginning. But as the workout goes along the participants begin to unknowingly tire and their effort on the intense interval gets less and less. Therefore, their "rest" time becomes longer and drops the heart rate more each time. Basically, it is like being on a treadmill at 7 mph and every few minutes dropping it down; at the end, you are at 5.8 mph and ultimately your average heart rate for the whole workout is less than you think even though you "feel" it was a good workout.
This does not make interval training a bad workout. If you enjoy doing it or, it is what motivates you to go to the gym, then continue. But I cannot tell you how many people have come up to me asking why they are not seeing results even though they are doing HIIT workouts. The answer is in the data. Whenever anyone has come to me with this issue I will have the
m wear a tracker for a HIIT workout and then put them on a piece of cardio equipment for the same amount of time and review the data with them. And almost every time they see that their average heart rate and calories burned is higher on the piece of cardio equipment than the HIIT workout.
Again, the point here is: HIIT is not a magical workout just because it is HIIT. The secret to any cardio workout success and, making every workout count, lies in knowing and quantifying how hard you are working. And, having an expert coach ensure the heart rate you work at will get you results. The answer to that client's question earlier of "Why am I doing HIIT but not getting results?" is found right in the data.
I am not trying to talk anyone out of their favorite interval workout. But after six long years of studying cardio exercise training, I have found so many things we have been doing wrong for so many years. So I have made it my goal to get the truth out so everyone can make sure the valuable time they spend exercising gives them the results they are working so hard to achieve.