The Hulk Factor

TAGS: hulk, kiefer, low carb, Nutrition

A miasma of fear rolls over you, the stank, noxious fumes carried by one of the most dreaded phrases in the strength training world: low carb. Once you ditch the carbs, you know what’s lurking around the corner, stalking you, breathing a cold chill at your neck.


Weakness just bit you in the ass.

The last 15 years has seen an interesting array of dieting strategies for everything from shredding down, to clean bulking and even tweaks for staying strong on the road, to getting ripped. In the hail storm of options, low-carb falls with the shredding ilk and pretty much defines the category, and who the hell would ever suggest low-carb for strength?

I won’t lie — lethargy is no stranger during the first two weeks or so of an ultra-low carb diet, like my own offering, Carb Nite®, but if you’ve learned from my work, it’s that I like to make ass-backwards suggestions. At least I don’t just pull this stuff out of my ass…

A few years ago, after a software job, lack of training and ad libitum eating debilitated my body, I jumped in feet first and decided to fix everything at once. This was before I had formulated Carb Back-Loading™  and, being partial to what I know, I started Carb Nite along with a 6-day-a-week training split. I didn’t care about maximum strength, only aesthetics. The training together, with a modified version of Carb Nite, leaned me down from a chubby 240 to a chiseled 204. Having the extra fat and muscle memory allowed me to regain some mass and lose the fat at the same time.

Something more interesting happened, something I didn’t expect. My strength started going through the roof — in the gym. Of course in the gym, right? I emphasized "gym," because I almost felt weak during my normal daily activities in comparison. Once I slipped under the bench bar, pinched my shoulder blades and pressed the weight from the rack, a change occurred. When I stood up from the set, I was shaking like I’d just taken a couple grams of caffeine. The unknown welled-up inside and…I was strong as fuck for the rest of the workout.

My numbers on bench — and everything else — kept going up. For a few weeks I had trouble with 225 pounds, then I was at 275, 315, 365, 385…there seemed to be no limit. Then, on a training-by-invitation trip to Team Samson’s gym in Florida, I hit 405 at a measly body weight of 202. I felt bad ass — in the gym. Outside of the gym, I still felt like I was all-show, no-go. Some crazy bio molecular process imparted a Hulk-like effect every time I wrapped my hands around steel with the intent of smashing it.

Physicist, observation, no explanation: I could not leave this alone. Like always, I started digging, starting with what I knew, either confirming or denying ideas along the way. The explanation I found hit me as rather straight-forward, even if a few pieces were unexpected.

I should also bring a little specificity to the conversation because low-carb, these days, can mean anything. Everyone seems to have their own personal flavor of low-carb, many of which aren't low-carb at all. So when I'm talking low-carb I mean, specifically, 30 grams or less of usable carbohydrates per day. That's about 4 saltine crackers worth of carbs. Usable, by my definition, does not include fiber since fiber can only provide energy once it ferments into short-chain fatty acids in the colon1, 2. Fiber, a carbohydrate, provides energy as a fat.

Some people may argue with my definition of low-carb, but the research shows that all the effects attributed to a ketogenic diet occur at 30 grams or less for just about everyone; once carbs comprise a greater amount of daily calories than that, the results become fuzzy at best3-18. Thirty grams, that's it.

Before I go into why The Hulk Factor exists and how it works, not only is defining low-carb necessary, but so is dispelling a bit of fitness-industry folklore. Glycogen levels — the carbs stored in the muscle — do not affect strength19-22. Trust me, on 30 grams or less of carbs per day, you're going to exhaust glucose reserves in a day or two. Once that happens, you obviously cannot escape training with depleted glycogen stores.

For the energy requirements needed for strength (but perhaps not to cover your normal training volume), fat can take up the slack on a low-carb diet. Realize, this may not correlate to your maximum lifting weight, as depleted glycogen stores can and will change the mechanics of your lifts. Empty glycogen stores also seem to have no bearing on resistance training’s ability to stimulate muscle growth23, and might be advantageous for accelerated fat loss24, 25.  Glycogen levels can affect recovery rates, however, but that’s a topic for another day.

Glycogen depletion won't hold us back during our low-carb training, so what is it that propels us forward, that gives us The Hulk Factor? A combination of enhancements to the central nervous system and sympathetic nervous system create The Hulk Factor, enhancements that may be more of a result of the absence of carbs rather than the addition of added fat and protein for fuel.

First, the central nervous system appears to function with greater efficiency when we strip carbs from the diet. Motor-signals increase in amplitude26, allowing an increase in single-rep power production, and fine-motor control27. The literature refers to the latter as psychomotor performance. Going sans carbs augments your ability to coordinate movement, such as holding form while lowering 800 pounds perfectly into the groove of your bench shirt.

These two didn’t surprise me much. When you eat carbs through the day, you’re trying to maintain blood sugar levels by external means, giving the body a load all at once, one it must disperse and deal with in order to regain homeostasis. As neurons contain massive amounts of GLUT3 transporters which can suck up glucose at will28, cell function and efficiency is sensitive to swings in blood sugar level.

If we let the body manage its own production and management of blood sugar, the nervous system can stay fine-tuned and ready to perform. You might think it impossible for the body to maintain blood sugar levels without eating carbs, but blood sugar content at any one time is only four grams29. Not a difficult amount to maintain and an amount that the body can supplement with ketones, another high-efficiency fuel for nerve tissue30.

As nice as these two advantages of a low-carb diet are — power and coordination — they still don’t explain the transformation I experienced at the beginning of each workout when I performed my first set. These CNS effects don’t strike like lightening. The reaction seemed more like someone flipped a switch. That's because the sympathetic nervous system produces the drastic change. The sympathetic nervous system controls catecholamine response, and the most well known catecholamine is adrenaline.

Whenever you train, your body releases catecholamines, which increases fatty acid release, energy production and strength. The response of your muscular system depends on how much adrenaline is present, how fast it’s released and how sensitive cells are to adrenaline. Going low-carb does something to intensify each of these components31-36.

For starters, the adrenal glands release catecholamines with less stimulus or stress than normal when going low-carb. That's why after a moderate warm up set — and sometimes a light one — adrenaline flowed through my veins as if a bangle tiger lept from behind the dumbbell rack and scared the shit out of me. All I had to do was get down under the bar, do a few reps and the superchargers fired.

Responding sooner, awesome; responding with a larger volume of adrenaline, bad ass! This is another side-effect of a nearly carb-free diet. The flow of adrenaline starts sooner and the body dumps larger quantities: that’s not too far from someone plunging a six-inch needle into your chest and injecting a bolus of adrenaline into your heart, a la Pulp Fiction.

All this adrenaline slammed into the system and — here's the bonus — your cells are sensitive as hell to it. Driving the body into ketogenesis increases cellular response to catecholamines. When you put all this together you get fight-or-flight times 10. Power, strength, irritability and maybe even a bit of rage mixed together for the baddest-ass workout of your life...and if you adopt a low-carb lifestyle, this is your normal response every time you train. You can summon the Hulk whenever you want: just start throwing iron around.

I'm sure you don't want to live low-carb if you're a strength athlete. It's not fun and you will end up modifying your training to compensate for the lack of endurance, but damn if you don't want to bring out the green demon for a steel-stomping session. Just the feeling of rage-tainted power might be worth it. What I've found — and no, I actually have no research for this one yet — is that the effect lasts up to a month after transitioning from a low-carb diet back to normal. I have also found, if you use Carb Back-Loading appropriately, you can summon The Hulk Factor for months.

So shed the carbs and go smash shit.

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