For quite a long time now, health and fitness researchers have been preaching that strength training is an important component in a weight loss program. But over the past several years, with the advent of commercial programs like P90X, Insanity, CrossFit and others, strength training has evolved from something involving long hours of slow sets in the gym to something approaching what I would call balistic movement with resistance. And the truth is, both forms of strength training can be effective for weight loss (as well as for building muscle and gaining strength, obviously), but there is a problem with both of these types of workouts – they are not safe for the majority of the population, and not even for those who are quite fit.
An old-school weight workout, which the fitness world has lately given the shiny new moniker “High-Intensity Resistance Training (HIRT)”, involves lifting very heavy weights for a few (6 or so) repetitions, resting for two or three minutes, then doing it again three or four more times before moving on to the next exercise. This type of training creates major metabolic changes in the body (especially the muscles and the systems servicing those muscles), but it is A) very time-consuming and B) very hard on the joints of anyone over the age of 30, regardless of how fit or strong they are.
The “muscle confusion” workouts of late-night infomercial fame have turned those gym workouts on their heads, lightening the loads to little or no weight (in the case of bodyweight exercises) and increasing the number of repetitions in a set to dozens upon dozens. From a scientific standpoint, challenging the muscles in this fashion does create big metabolic changes, but these workouts have been widely criticized by professional reviews for subjecting users to high rates of injury. The reason is that working out in this fashion exhausts the targeted muscle groups very quickly, and then gives them little or no recovery time before moving on to another equally exhausting move. Form is compromised early on, and once form breaks, connective tissue won’t be far behind.
What Metabolic Resistance Training does is sort of marry the two workouts. It combines lighter weights with higher reps and moves quickly from exercise to exercise, but it allows for a muscle group to effectively rest before working again by the design of the sequence. By using lighter weights there is less stress on the joints, and by performing high-ish repetitions, the muscles are worked to the point of fatigue with each set, creating those desirable metabolic changes.
The result of an MRT workout is a body that feels totally exhausted but not hurt, and a metabolism that will continue to burn calories at a higher rate for minutes or hours after the workout – a phenomenon known as excess post-exercise oxygen consumption (EPOC).
Sounds easy enough, right? Wrong! This is not the circuit training of the 1980′s, where you broke a light sweat and dabbed the back of your neck with a gleaming white towel while sipping from a bottle of Evian. To reap the benefits of MRT, you need to be in great discomfort at the end of every single set. You should be breathing hard at the end of every set, and your muscles will be “feeling the burn” throughout the entire workout. The payoff for this agony is not only more calories burned during the workout, but more calories burned immediately after the workout – and all of the time, once you’ve been doing it long enough to enjoy some permanent changes to your metabolism.
MRT is not the sort of workout you do three times a week for the rest of your life (that workout doesn’t exist, by the way). It’s the kind of thing you want to work into your rotation for about 6 to 8 weeks (what trainers call “periodization”), then do something else for 6 to 8 weeks, and so on.
For the basic rules on how heavy you should lift and for how many repetitions, see Part I of this post.
Now, if you’re ready to shake up your routine, then here are three different MRT formats you can use:
Paired Sets Construct a workout that includes “non-competing” pairs of exercises – alternating between upper and lower body, upper body and core, etc. Complete each pair as a stand-alone set and do multiple sets (start with two, work your way up to three or four) before moving on to the next pair. A typical paired set workout should include eight to twelve exercises (four to six pairs) that hit all of the major muscle groups, moving from large muscle groups to smaller ones. An example of a few non-competing pairs might be: Weighted Lunges/Lat Pull-Downs; Smith Machine Squats/Dumbbell Incline Presses; Back Extensions/Bicep Curls, etc.
Circuit Training This is just what it sounds like, but remember that this is not the type of circuit training we tend to think of. Every set should be done to fatigue, and you should move right along to the next exercise without stopping to chat or update your Facebook status. The circuit should flow from larger to smaller muscle groups with non-competing muscle groups in sequence (i.e. alternate upper and lower body, etc.) This workout will be slightly easier than the paired sets workout, so a fit individual can probably start with three times through and work up to four. Beginners, give it a once-through and if you’re feeling good, go for two.
Combination Training Combination training looks the most like those fad “muscle confusion” workouts. It combines strength moves with high-intensity cardio moves. The difference here is that each set is only done to the point of fatigue, and not to (or past) exhaustion. Alternate traditional weight lifting exercises or body-weight calisthenics (push-ups, sit-ups, lunges, etc.) with boot camp-style, short-burst cardio moves – jumping jacks, burpees, mountain climbers, skipping rope, etc. You’ll likely need to take twenty seconds to catch your breath every few exercises, but as soon as you’re ready to move on to the next one, go for it! There’s a fine line between proper recovery between exercises and dallying. Most people aren’t fit enough to do a workout like this for more than thirty minutes. If you’re deconditioned, start easy and aim for six to eight minutes your first time out.
As always, if you are new to exercise or just getting back into it, you should consult your physician before attempting to do this or any other type of workout. If you’ve been exercising four days per week or more and you feel like you want to step things up a bit, then give MRT a try. Just remember – don’t rush your repetitions and end each set with the last repetition you can do with perfect form. If you haven’t a clue as to how to design your own MRT workouts, visit my web site and book a session!