The short definition of metabolic training is completing structural and compound exercises with little rest in between exercises in an effort to maximize calorie burn and increase metabolic rate during and after the workout.
FYI, your metabolism (aka metabolic rate) is how many calories your body burns at rest. For more on calorie burn, check out How to Calculate Your Calorie Burn.
So that’s the short definition, but here’s a deeper look at metabolic training:
“Structural and compound exercises” are types of exercises that require a maximum amount of energy because multiple joints are involved like a Squat with a Press. Sitting down and doing a biceps curl is like the exact opposite of hard core metabolic training.
A metabolic training purist may tell you almost all exercises should be structural, which means the spine is loaded and the legs are engaged to some degree during the exercise. I think you can still make a workout metabolic without engaging the legs every exercise as long as the weight lifted is heavy enough, or the intensity of the exercise is very high. For example, doing a bench press then a chin up back to back can be quite metabolically intense.
Metabolic training is high intensity anaerobic exercise that makes you breathless. If you are completing a metabolic workout and you are not breathing hard and sweating, something is wrong. Ideally you should be lifting as heavy as you can and resting as little as possible between sets.
The downside in my mind of some metabolic training is that it can be so intense so that your lips turn white and you want to puke. Personally, I like workouts that are tough, but not so tough that I never want to work out again. From a 1 to 10 scale, the workouts that I do and those I designed for the BuiltLean Program are around 5 to 8 in terms of their metabolic intensity. If you are doing very metabolic workouts all the time, your body may not be able to recover properly.
The extreme of metabolic training is CrossFit, where a few intense exercises will be repeated in a circuit with little to no rest to push the body to its absolute limit. This training is usually reserved for seasoned athletes and the military, but more recently has been taken up by average fitness enthusiasts for better, or worse.
A metabolic workout should help create a burning sensation in your muscles as you are working out. So by your last rep of a given exercise, you should be feeling a burn in your muscles. While the depth of the muscle stimulation from metabolic training is not as deep as a bodybuilding program where you hit one muscle the entire workout, it’s still significant.
It’s not clear exactly what causes muscle burn (the old theory of lactic acid build up has since been debunked (See: 5 Fitness Facts You Don’t Know). We do know that with an increase in muscle burn comes a favorable hormonal response to help the body burn fat and/or build muscle. I’m a big believer in working muscles intensely and going for that muscle burn.
Below are just a few of the benefits of a metabolic style of training:
While metabolic training is not “aerobic” like going for a jog, some studies have shown anaerobic exercise such as HIIT can increase in V02 max beyond that experienced by exercisers following an aerobic program.
Several studies have shown that hormones that promote “lipolysis” (the technical term for fat loss) increase as a results of high intensity strength training. I don’t want to bore you with all the studies, but strength training in general has been shown to help improve hormonal profile, and metabolic training is debatably the best type of strength training to elicit the most powerful hormonal response.
While calorie burn studies come to different conclusions as to the total calorie burn of metabolic training, it certainly burns a ton of calories. The calorie burn during a workout is easily around 500 calories for a 30 minute workout, but it also increases metabolic rate from anywhere between 10% to 25% for up to 48 hours, with some studies showing an increase in metabolic rate for up to even 72 hours. This equates to hundreds of extra calories, which over the course of a few workouts can become significant.
Intuitively I think the “afterburn effect” as it’s called makes sense, because you are shocking your body, creating an oxygen debt (i.e. excess post-exercise oxygen consumption), and causing muscle damage (in a good way), which the body needs to repair to become fitter and stronger. This extra repair to get your body back to homeostasis requires a lot of extra energy, it’s just difficult for researchers to measure perfectly, especially after exercise. From my practical experience, the metabolic effect of intense strength training is real and it’s powerful.
Here are just a few examples of what would be considered “metabolic exercises”.
I think making your workout more metabolic is worth a try and I find simply categorizing a workout based on its metabolic intensity can be useful.
Hope this was helpful!