A few days ago, I answered a Q&A on Around Workout Nutrition While Dieting and, mentioned in an offhand way that I would talk about the issue of weight training for fat loss at some later date. Well, apparently today is that later date. Or, more accurately today and Friday since, as this is going to be long, I’m going to divide it into two parts.
Today, in Part 1, I’m going to look at some basic concepts and look at the impact of two different ‘types’ of weight training on fat loss while dieting. As usual, I’ll look at the pros and cons of each and you’ll even get an almost practical recommendation by the end of it.
In Part 2, which I’ll put up on Friday, I’ll address practical issues of how to put together a weight training program during dieting in terms of volumes, frequencies, scheduling, etc.
The Fundamental Goal of Dieting
First it may be helpful to look at what the actual goal of dieting is. As I’ve discussed in every book I’ve written, and in the article What Does Body Composition Mean?, while many are still fixated only on changes in scale weight, the goal of dieting should primarily be focused on fat loss. Implicit in that, and this is especially true for folks who toil in the weight room, is that there should be a maintenance of muscle mass.
So that’s the basic goal of a diet: losing fat while maintaining (or at least minimizing the loss of) muscle mass. Simple enough in premise but often more difficult to achieve in practice.
I’d note that there is actually one potential exception to the above: in the cases of extreme obesity, many researchers feel that allowing up to 25% of the total weight loss to be lean body mass is not only beneficial but may be necessary to achieve anything approximating a ‘normal’ body weight (whatever ‘normal’ means in this context).
The reason is that, while becoming obese, a portion of the weight gained is lean body mass. A good bit of this is connective tissue and other ‘support’ tissue for the increased weight but some of it is actual muscle mass as well. Some researchers differentiate between inessential lean body mass (connective tissue, etc.) and essential lean body mass (organs, muscle) for this reason.
But outside of that exception, let’s start from the assumption that the primary goal of dieting is to lose fat while maintaining muscle mass (or at least minimizing the loss of muscle that often occurs).
Classic Fat Loss Training
An idea that has been prevalent for quite some time (going on at least four decades and probably more) is that the fundamental nature of weight training should change when the goal moves from mass or strength gains to fat loss. The idea of using high-repetitions with short-rest intervals to ‘get cut’ has been part of the bodybuilding subculture for years and shows up in the training ideas of the general public as well.
Personal trainers talk about training for definition or tone (versus size or mass) and I assume anybody reading this is familiar with many of the popular metabolic type weight training workouts (e.g. Turbulence Training, Afterburn, etc.) that are often suggested when fat loss is the goal.
This is often accompanied by wholesale changes in exercise selection: ‘mass building’ exercises such as squats and bench press are often replaced with ‘cutting exercises’ such as leg extensions (burn in the cuts, bro) and cable crossovers.
An additional idea that most likely came out of the drug use of late 70’s and early 80’s bodybuilding practices is that training frequency and volume should go UP while dieting. Before addressing anything else I want to address that. The basic idea of increasing either training frequency or volume in the weight room while dieting is completely ass-backwards on a tremendous number of levels. If there is a single time when overall recovery is going to be reduced (unless you are using steroids), it’s when calories have been reduced. Trying to train more frequently in the weight room on a diet makes no sense.
I’ll come back to this more in Part 2 on Friday.
Metabolic Weight Training vs. Tension Oriented Weight Training
For the purposes of this article, I’m going to divide training rather simply into two different categories: metabolic weight training and tension oriented weight training. First some definitions.
By metabolic type weight training, I’m referring again to the higher rep/short rest types of training that are often suggested for fat loss on a diet. Loading might be something like 4 sets of 12-15 repetitions (or more) with 30-60 seconds rest or less between sets. I’ve described this type of training before, for example, The Ultimate Diet 2.0 uses exactly that type of training at the start of the cycle to deplete muscle glycogen and maximize fat burning.
Tension type weight training refers to more traditional heavy weight training. Lower repetitions with longer rest intervals: this might be sets of 5-8 repetitions with 1.5-3 minutes rest between sets or what have you. Just your stock standard traditional type of heavy weight work.
Now, as you’ll see, each of these two types of weight training has certain pros and cons in terms of their effects while dieting. Let’s look at each.
Metabolic type weight training tends to generate a higher calorie burn than traditional low rep training, the glycogen depletion that occurs increases whole body fat oxidation, and the hormonal response is actually quite similar to interval training (in The Stubborn Fat Solution, this type of training can be used to kick off the more intense Stubborn Fat Protocols 1.0 and 2.0).
Of course, many find that their top end strength falls somewhat while dieting; as well, when people get very lean, joints often get a little bit wonky under heavy loads. The lighter loads used in metabolic type work can be beneficial in that regards as well.
So those are the pros for this type of training: increased calorie burn, a nice hormonal response, easier on the joints, depleting muscle glycogen enhances fat oxidation.
Here’s the bad.
As I’ve mentioned repeatedly on the site, the primary stimulus for muscle growth is progressive high tension overload (e.g. adding more weight to the bar over time). Without getting into a big old technical discussion of protein synthesis and breakdown here (you can read The Protein Book if you’re interested); I’ll simply say here that the high tension stimulus that builds muscle is the exact same high tension stimulus that will maintain muscle mass when you’re dieting.
So perhaps you can guess what happens to muscle mass when you reduce weight on the bar to use higher reps and shorter rest intervals. When you remove the high tension stimulus, you remove the signal to build (or in the case of dieting, maintain) muscle mass. What do you think happens next? Right, muscles get smaller.
Many natural bodybuilders have found this out the exceedingly hard way by trying to copy the pre-contest training of drug-using bodybuilders. Without the drugs (to maintain muscle mass and protein synthesis even in the face of the diet), natural bodybuilders watched their muscle mass shrink when they started training lighter with higher reps. Without the high tension stimulus of heavy training, the body simply has no reason to maintain muscle mass.
And that’s the bad of metabolic type weight training: while it has certain benefits that I listed above, it is an insufficient stimulus, for maintaining muscle mass (with one exception). At least if used by itself.
That exception is beginners. Complete beginners, who haven’t built any real muscle mass in the first place don’t have to worry much about muscle loss while dieting (just about any training will maintain it).
But for trained individuals beyond the beginner stage, using metabolic type weight training exclusively on a diet is a recipe for disaster. Please note the use of the word ‘exclusively’ in that previous sentence. I’ll come back to this in a second.
I imagine you can see where this is leading: outside of any other pro or con of heavy weight training, the biggest pro of all of heavy weight training on a diet is that it best maintains muscle mass. And since that’s one of the explicit goals of dieting…
Of course, the cons are basically the opposite of what I listed for metabolic type weight training: the calorie burn is generally lower (I’d note that the calorie burn from weight training is rarely massive in the first place), you don’t get much glycogen depletion, you don’t get the hormonal response.
But in this case, at least within the context of the primary goal of a diet (lose fat/maintain muscle), none of that matters. Put simply, if someone had to choose ONE type of weight training to perform on a diet, it would be heavy tension oriented training while letting the diet/cardio type work handle the fat loss. I’ll cover loading parameters in Part 2.
In fact, that’s exactly what I recommended in The Rapid Fat Loss Handbook: 2-3 short heavy weight workouts per week (to maintain muscle mass) while allowing the big caloric deficit of the diet generate fat loss. And it works.
Alternately, you could combine 2-3 short heavy weight workouts with cardio and use a smaller dietary deficit. And that works too. What won’t work (for anyone not using drugs) is to remove the heavy tension stimulus completely and move to nothing but higher reps and lighter weights.
Well, not unless you define ‘work’ as losing muscle mass.
But, you say, why does it have to be one type of training or the other? And clearly, it doesn’t. There’s no fundamental reason why both kinds of training can’t be done while dieting. More accurately, there’s no reason that metabolic type work can’t be added in some fashion to properly performed heavy weight training. This can give the pros of each while eliminating the cons of each at the same time.
So how do you do this, how do you combine the two types of training? That’s in Part 2.