Burning fat and building muscle—at some point you've probably tried to do both. There's a lot of advice out there about how to manipulate everything from rep schemes to exercise selection to match your goals, but how much of it is rooted in reality, and how much of it is B.S.?
In order to understand the role training plays in both hypertrophy and fat loss, it's important to have a basic understanding of the mechanisms behind each. As we'll find, there there are both differences and similarities between the best workout for each. Whether you're bulking or cutting, this is for you.
Sports Cars and Savings Accounts
Muscle tissue is a luxury. Having a bunch of it is the evolutionary equivalent of owning a sports car; the extra horsepower is nice, but unless you're using it to do something more demanding than run to the grocery store, the cost of upkeep probably isn't worth it.
Fat, on the other hand, is a savings account. It's our body's way of storing energy for times of need; when things are going well and we have a little extra, we tuck it away in our biological bank account for a rainy day. The trouble is, most of us haven't seen the metabolic equivalent of a "rainy day" in years. Our lifestyle has outpaced our biology, and the results aren't always pretty.
Manipulating your body to build (or hold onto) muscle while shedding fat is akin to convincing a doubting spouse that they should let you dip into your joint savings account to pay for a convertible. I've never tried it, but from what I hear, it can be a bit of a trick.
So how exactly do we go about "convincing" our body to do what we want it to? Stress.
Stress, a Hormonal 'Lingua Franca'
If hormones are the language of the body, then stress is the common tongue (or 'Lingua Franca'). Regardless of the hormone involved, its production and release is regulated by perceived stress. Too much blood sugar? Let's get some insulin going. Too little? Time for some glucagon. Need some quick energy? Here's a nice little cortisol/adrenaline cocktail to go with that glucagon to get you going. The common thread isn't the target action of a specific hormone, it's the presence of a stressor to trigger the hormonal response.
What's that mean for you, the guy or gal just looking to get a little more jacked or to cut up a bit? Two things in particular:
You need to apply enough stress to drive a change—imagine your body as a lazy teenager stuck in bed; it's gonna take a lot to get them moving.
You need to apply the right kind of stress to drive the change you're looking for—water boils and freezes in response to stress, but throwing water onto a fire is a terrible way to make ice. Be specific.
"One Pill Makes You Larger, And One Pill Makes You Small..."
As mentioned earlier, hypertrophy and fat loss live at opposite ends of the biochemical spectrum, one being anabolic and the other catabolic, respectively. Anabolic reactions involve building complex molecules from simpler ones, while catabolic reactions break larger molecules down into smaller ones. We can avoid a discussion of the specific chemicals, compounds, and reactions involved—and save everyone a headache—and understand that, while not diametrically opposed, building muscle and burning fat involve driving in opposite directions.
*A side note. This reality is the nasty secret behind the holy grail of the physique world: simultaneously burning fat and building muscle. While there may be avenues for this to occur, they're likely limited, and less common as we approach the outer limits of body composition. As Confucious said, "The man who chases two rabbits catches neither." At a certain point, particularly if you're already in decent shape, you need to pick a goal and go after it.
Throwing water onto a fire is a terrible way to make ice. Be specific in your training.
A Specific Kind of General
To summarize: muscle is expensive, fat is protective, stress drives change, and that stress needs to be specific to the goal.
Now that that's clear, let's muddy the waters a bit. It turns out that sometimes the specific stress we're after is specific, and sometimes it's actually best described as general. Confused? Good, that just means you're paying attention. Let's clear things up.
In order to convince your body to grow, say, bigger biceps (ears perk up), the biceps need to be stressed. Going for a run, eating less, and holding your breath all provide different forms of stress, but none of them are gonna build (Hulk Hogan voice) "24-inch pythons, brother!" In order to do that, you need to stress the biceps themselves.
Hypertrophy requires the accumulation of localized, specific fatigue, and your training program should be set up to allow you to create enough specific stress to create that fatigue.
Where hypertrophy requires specific fatigue, fat loss requires general fatigue. Rather than trying to stimulate a group of muscles, the goal in training for fat loss is to stress the entire system, and too much localized fatigue can actually limit our ability to apply this broader stress.
Taking things a step further, if hypertrophy is the goal, your programming needs to provide localized fatigue while avoiding systemic fatigue. If fat loss is the goal, our priorities flip, and a good program will favor systemic fatigue while minimizing localized fatigue.
It's a biological balancing act, and balance can be found through a variety of means, a few of which we'll explore below, but which includes everything from exercise selection and order to sets and reps, rest periods, and loading strategies.
Methods, Madness
The following discussion is meant to take a macro view of things: there are simply too many potential variables to consider, and each situation will be slightly unique. Rather than getting lost in the details, my hope is to provide a framework you can apply as you go through the problem solving process that is programming.
I see seven training variables as key to building a focused, effective program, and group these into tiers reflecting both their relative importance as well as their relationship to each other:
Exercise selection
Exercise order
Session structure
Training volume
Work density
Objective Intensity (loading)
Subjective Intensity (perceived)
Tier 1: Exercise selection and order. While they're almost indisputably the king and queen of the hill, they also influence each other, and have an impact on subsequent variables. If I choose three biceps exercises I've already written 80% of the program—things like volume, structure, and density may not be written in stone, but they've been clearly outlined. Despite—or maybe because of—their importance, I often work backwards and find exercises that support the kind of workout I want to design. Regardless of your workflow, answering these two questions deliberately will make everything else more effective.
Tier 2: Session structure, training volume, and training density. The interplay between these variables should be fairly obvious to anyone with some experience: how I structure a session (straight sets, compound or super sets, circuits etc.) informs both training volume and density (work per minute). Straight sets limits work density, while circuits maximize it, and training volume is a function of density and time.
Tier 3: The kind of intensity your programming drives reflects the kind of fatigue it's creating. As such, the relative importance of both objective and subjective intensity varies. As the third and final tier of exercise variables, intensity is hugely influenced by other variables—if your back squat follows a few rounds of leg extensions and split squats both the load and the perception of that load will be impacted.
Program design is like a very particular form of algebra, in which you're given a limited number of fixed values—their goals, constraints, etc.—and asked to solve for x. As you do so, remember our mantra: hypertrophy requires specific fatigue, while fat loss requires general fatigue.
The Least I Can Possibly Say About Nutrition
Hypertrophy requires a caloric surplus, adequate protein to support muscle growth, and sufficient energy—preferably as carbohydrates—to support intense and prolonged training sessions. Fat needs to be kept at or above baseline levels in order to support hormone production.
Fat loss requires a caloric deficit, and slightly elevated protein intake to help spare skeletal muscle mass. The ratio of macronutrients typically shifts in favor of fat and protein in an effort to protect skeletal muscle mass and baseline fat intake, often resulting in reduced carbohydrate intake.
In both cases a modest deviation from maintenance levels is preferred.
Take Home
It's easy to get lost in the weeds, particularly for those us who enjoy delving into the details. A few key points for when things start to get a little fuzzy:
Apply enough stress to provoke a change.
Separate specific fatigue from general fatigue, and use them appropriately.
Don't forget the two other training variables: adherence and effort. Write a program that encourages both above everything else.
If you've found this helpful I'd appreciate a share or two—social media, email, word of mouth, whatever. Thanks in advance!