Jade Teta ND, CSCS
For those who have been a part of Metabolic Effect for the last 5 plus years, you may be surprised to hear a lot of talk about metabolic exercise lately. For awhile it felt like we were the only ones training this way. In 2004, my brother Keoni and I wrote a paper entitled Hormonal Weight Loss: Is There Such a Thing as the Metabolic Effect. Since then it has been updated several times and has been widely distributed across the net, handed out at medical conferences, published in the international alternative medicine journal Townsend Letter, and inspired many to convert their exercise practices to be more in line with this science. Currently, the fitness industry is on the verge of exploding this new fitness genre onto the market. We of course are excited about the recent clamor surrounding this new way of exercise, but like with all things we are already seeing the concept morphed into something it is not. So how do you know if your trainer is really doing metabolic conditioning or just think they are?
What it is not?
Lets first cover what metabolic conditioning is not. Metabolic conditioning is not interval training. While interval exercise can be an important component of metabolic exercise, the metabolic approach is much more than that. Metabolic exercise is also not aerobic exercise. If the body is not being pushed into the anaerobic zone (supra-aerobic) at times, you are not doing metabolic conditioning. It is not powerlifting or bodybuilding. If you are taking long rests between sets, avoiding elevating your heart rate, and your workout lasts longer than 40 minutes, then you can be pretty sure you’re not doing metabolic exercise. Finally, and most importantly, if you are standing on one leg while your trainer tosses balls for you to catch or running through an obstacle course (what we call a distraction course) you are not doing metabolic training. Oh, and by the way, boot camp is not synonymous with metabolic training; most boot camps are simply aerobic exercise sessions with built in distractions to keep you from getting bored.
What it is?
Metabolic conditioning is no joke, and when you are doing it you will know it. Actually, most people know exactly what it feels like; they probably just don’t realize it. Have you ever been in a tug-o-war battle that lasted over a minute? Or chopped down a tree with an old-fashioned axe? Pushed a heavy wheelbarrow up a hill? Spent all day digging a hole? Or played virtually any contact sport that involved all out effort imposed on an object that was pushing back on you (martial arts, wrestling, American Football)? If you have then you know exactly what metabolic training is.
In these types of movements you are not aerobic or anaerobic you are both. You will spend periods of time in the aerobic zone and periods of time above the lactate threshold. You are not just doing cardiovascular training or resistance training you are doing both. Your not isolating any particular area of the body, you are simultaneously exerting every muscle you have available. You will be moving up, getting down, exploding through a set of heavy squats, repping out as many push-ups as you can, and blasting through a 1-minute sprint. And all of this will be done with little rest between exercises. You will usually be carrying some sort of weights with you throughout the workout, abandoning them only briefly to complete a sprint drill or two. Metabolic training is often described as getting sucked into a vortex with a pair of dumbbells.
Metabolic conditioning is not about building bigger muscles, decreasing heart disease, or improving performance, although it definitely will help with all three. Metabolic exercise is about burning the maximum amount of calories (specifically fat calories) possible during a workout. It is also about generating a metabolic “ripple” effect that will burn fat for many hours after the workout. This sounds like marketing hype to most people, but this is exactly what research has shown is possible and what metabolic training attempts to produce. If the workout is done with sufficient intensity, and the diet is in-line, it can even ignite fat burning for days.
There are many studies that look at different forms of high intensity exercise, but a study printed in the September 2008 issue of The Journal of Strength and Conditioning Research demonstrates the impact this style of training can have over a more traditional approach. In this study two exercise sessions were compared. Each workout was identical in terms of the amount of work completed (volume of exercise was the same); the only difference was the order of how things were done. In one workout the resistance training and cardiovascular portions were done separately and completed one after another. In the other program, the resistance-training workout was completed with the cardiovascular component inserted between exercise sets. In other words, the workout was intermixed with periods of weight lifting and cardiovascular exercise integrated together. The amount of sets, reps, and weight lifted were the same in each workout and the total amount of cardiovascular exercise was equal. Despite the identical workload, the intermixed workout produced a ten times greater fat loss compared to the separated workout. Surprisingly, the intermixed group also saw better gains in muscle mass. Strength and endurance were improved in the upper body to a greater degree with the separated workout while lower body strength and endurance were better with the intermixed workout.
The results of the intermixed workout above are impressive, but metabolic exercise goes even further. This is because the weights in the intermixed workout were relatively light and machines were used rather than free weights. This is an important difference. Metabolic conditioning gets its name mainly because it activates the 3 major energy systems in the body. The phosphagen system (for explosive movements lasting seconds), the glycolytic system (essentially anaerobic metabolism), and the oxidative system (essentially aerobic metabolism) are the three energy systems I am referring to. In addition, it activates two other mechanisms responsible for the associated after-burn. EPOC or Oxygen debt refers to the elevated oxygen consumption after a workout is complete and can result in significant fat calorie usage for hours and days. EPOC is triggered mainly by the release of stress hormones (catecholamines= epinephrine/norepinephrine or in Europe Adrenaline/Noradrenalin). A large catecholamine surge coupled with exhaustive exercise will push the body to generate large amounts of lactic acid, which then triggers the release of growth hormone (HGH), and testosterone. This “chemical soup” of hormones is what drives the EPOC after-burn. The biochemical combination of stress hormones (cortisol, adrenaline, noradrenaline) with growth hormones (HGH and testosterone) creates an accelerated state of metabolism to mobilize stored glycogen and fat and repair damaged muscle tissue. This “hormonal cascade” is released under very high intensities whether it is the stress of heavy weights, exhaustive sprinting, or high repetition lactic acid generating movements. In order to achieve the desired impact, all these factors need to be included with shorter rest periods that are just long enough to recover and generate the same intensity again.
In addition to EPOC, there is something else that exercise research overlooks and that is heat. EPOC alone cannot account for the massive metabolic effect generated in this style of training when it is done correctly. Heat is generated to a significant degree during this style of training. However, there are no tools readily available outside of a laboratory to measure the energy lost as heat. Researchers have shown that up to 40% of the energy burned in a high intensity workout cannot be accounted for because of the inability to measure this heat loss. This means you burn a third more calories with this style of training than would be predicted through calorie counters and EPOC calculations.
Putting it together.
So, if you want to know if you have done a metabolic training session or not, 4 specific criteria need to be met. I call them the “Bs” and “Hs”. They are Breathless, Burning, Heavy and Heat. To accomplish the benefit of true metabolic training these goals should be met in each and every workout.
1. Get Breathless- you have to be panting for breath in a metabolic workout. If you can talk, you are not doing metabolic conditioning. This aspect correlates with the degree of EPOC and catecholamine release.
2. You need to get Burning- You have to get to the point of metabolic failure. This is a term I use to describe the need to stop because of an intense burn in the muscles, not necessarily because the weight is too heavy. This is directly related to the lactate generation in a workout and how much growth hormone and testosterone you will generate from the workout (more a HGH determining factor than a testosterone one)
3. You need to lift heavy- if you are not incorporating heavy weighted movements into the workout you are missing it. Heavy barbell squats, explosive power cleans, and maximal dead lifts are key. If you don’t have weight, then you need to use body-weight exercises that come close to mimicking the same effect (single leg squats, pull-ups, push-ups, explosive jumps, and other plyometrics). This one is all about the type II fibers. Heavy weights trigger HGH and testosterone (more testosterone than HGH). This is what I call mechanical failure. As opposed to metabolic failure, this is when the weight just gets to heavy to overcome gravity.
4. You need to generate heat- the final parameter is heat. If you are not sweating, your body is not getting hot enough. As a matter of fact, I use the ability to sweat as a biofeedback tool into how sensitive the body is to its catecholamine response. If your not sweating in a workout, you are missing out on this heat effect.
A few final words on metabolic conditioning. First, the unique hormonal response of this type of exercise is what drives the results NOT calories. Anyone who tells you different just does not understand his or her endocrinology. It is true, calories must be burned, but it is hormones that determine what type of calorie you will burn, sugar or fat. In addition, Intense exercise such as this can always push the body into a state of muscle break down (catabolism). Research on cyclists has shown that intense exercise sessions lasting over 40 minutes push the stress/growth equation more towards catabolism then towards anabolism (gain of muscle tissue). The ratio between catabolism and anabolism needs to be balanced so that fat can be burned while muscle is gained or at least maintained. Besides, if you are really dong metabolic conditioning you will not be able to go past 20 to 30 minutes. If you do, then you are pacing yourself and likely just doing an aerobic zone workout. If that is what you want, just go do any standard boot camp workout. Pacing in this workout is the last thing you want to do. Push hard, and then rest until you can push hard again. That is the way it is done. When the workout is kept short, generating enough intensity is not a problem, but as the duration increases pacing usually ensues. 10 to 30 minutes is usually all it takes.
Second, true metabolic conditioning is individualized. Everyone’s sweet spot is a little different. This is why one-size-fits-all-circuits with defined rest periods are not as effective. Circuits done in sets with defined rest periods are trying to fit the old do-a-set-and-rest-model to metabolic conditioning and it only serves to decrease the effect. In order to get the proper response, people should rest just long enough to be able to push hard a second time. We teach our certified trainers to think of the phrasing “push till you cant, rest until you can”. The harder people push the more they will have to rest, and the more they rest, the harder they will push and the greater the metabolic stimulus they will enjoy. The reason we call our system Metabolic Effect with the acronym ME, is because our rest-based technology allows each individual to know how hard to push, when to rest, and when to start again. This is not based on some predefined rest segment but on their own metabolic ability. This is what metabolic conditioning should be and what the metabolic effect is all about.
If you are interested in more of the research on metabolic exercise and our approach, or you want to get certified in our methods, we would love to talk to you. More top-notch trainers schooled in the science and application of metabolic exercise are needed soon or metabolic exercise is going to become another word for the same tired exercise programs. Check out my and Keoni’s article in the next Onfitness to learn more about metabolic conditioning or contact us to sign-up for an online certification.