The Case for High-Carb Massing

by Dr. Mike Israetel, Co-founder and Chief Sport Scientist and Broderick Chavez | Jan 09, 2018

The Case for High-Carb Massing

This article is about how to gain the most muscle possible. If you’re looking for any other kinds of info, our apologies. But if you’re looking to add some in-depth details to your knowledge on how best to gain muscle, please feel free to keep reading!

Fundamentally, muscle gain is about doing 3 very basic things. Thing #1, as Dr. Seuss might say, is to train hard. We’ve got plenty of other sources of information about that here if you’re interested.  Thing #2 is to eat a hypercaloric diet. That is, a diet that brings in more calories than you burn on a consistent basis, which allows you to actually gain weight. Thing #3 is a sufficient amount of protein. In combination with weight training, getting enough protein means that the excess calories will actually build some muscle instead of just adding pure fat. After all, gaining just weight is not that hard (millions of people the world over do it all the time), but gaining muscle is much more challenging.

If you apply those three basics to your efforts, you’re going to gain muscle. The question of this article isn’t IF you gain muscle by doing such basics, but it’s the HOW MUCH muscle you gain (vs. fat) by manipulating details. The particular detail we’re focusing on here is the ratio of macronutrients of your diet and how it affects your muscle vs. fat gains. Sounds complicated, but luckily the basic question is quite simple. First of all, protein needs must be met with no negotiation, so about a gram of protein per pound of bodyweight per day is likely close to optimal for gaining muscle. Can you eat even more than this and use extra protein to make up a big fraction of your daily calories? Yes, but extra protein has at least two major downsides. First of all, it’s by far the most expensive macro. Secondly, it has such a profound effect on suppressing hunger that gaining weight by adding tons of extra protein turns into an incredibly uphill battle to get in enough calories. A battle that most people lose.

Because we can simplify things by just shooting for a gram of protein per pound per day, the big question of this article comes down to: “what’s the best ratio of carbs to fats for gaining the most muscle and the least fat in the long term?” We have to be very clear in that this is a DETAIL and not a main effect question. So long as you meet the three conditions described earlier, you’ll gain muscle in almost every case. And it’s also very likely that the difference in carb:fat ratios doesn’t make a HUGE difference in the amount of muscle vs. fat gained. However, over time, even small differences add up, and if you want the BEST results you can get, knowing even the details matters.

To navigate our examination of this question, we can postulate three different kinds of mass-gaining diets. The first kind is the “surplus fats” diet. Because it’s been shown that meeting carb needs is critical to performance and muscle gain, this kind of diet first meets carb needs daily (based on training volume and activity levels). So for example, if you’re highly active, train for 2 hours a day, and weigh 200lbs, such a diet might prescribe that you consume at least 400g of carbs that day. But if you add the calories of the proteins and only 400g of carbs, you’re not remotely in a caloric surplus. To get to that surplus, the “surplus fats” diet relies on filling the gap between “protein + carbs” calories and your hypercaloric calorie goal with exclusively fats. In the example above, this might mean eating about 175g of fats per day to get to a 4,000 calorie goal. This diet meets carb needs for performance so that you can train hard, but only adds fats once such needs are met and the calorie goal is the target.

The second kind of diet we can use to gain muscle is the Low Carb, High Fat diet (LCHF). This diet keeps carbs to their lowest reasonable levels (less than or equal to about 0.3g of carbs per pound of bodyweight per day, usually in just ancillary sources), while smashing TONS of fats to create a caloric surplus. In our 4000 calorie, 200lb athlete example, he might eat 200g of protein, only 60g of carbs, and a whopping 330g of fat per day!

The third type of diet we can consider is the High Carb, Low Fat diet (HCLF). This diet provides the minimal amount of fat (about 0.3g per pound) to support hormonal and other basic body functions, and then uses carbs to generate the non-protein calories. For our example athlete, that means he would consume 200g of protein, 665g of carbs and 60g of fat per day to get to 4000 calories.

Unfortunately, the direct research for such diet comparisons in individuals other than beginners is slim to none, so we’ll be relying on physiological rationale and indirect research for the most part. Let’s take look at that indirect evidence and physiological rationale by charting the benefits and downsides of each approach, hoping to figure out which one is best on the net balance for our goal of maximum muscle gain with minimal fat gain.

Benefits of “Surplus Fats”

There are two clear benefits to gaining weight on the “surplus fats” approach:

1.) Ease of eating at surplus

If you had to name your top 10 most delicious foods, we can almost guarantee you that they can easily fit into the macros of your “surplus fats” massing diet. By allowing the consumption of a combination of fats and carbs, nearly every delicious food can be included in your diet, making the consumption of lots of calories very easy. Think about it… cheesecake, burgers, pizza, ice cream. You name it, it probably has a roughly even combo of fats and carbs… something that neither of our other diets for mass can support much of.

2.) Least restrictive food choices

Not only are the foods possible to eat in “surplus fats” the tastiest, the macros here force the least restriction on your diet. So long as you can get some protein, you don’t have to look for super low carb or super low fat foods when out with friends, traveling, on the go, or even at home cooking your own food. Because of this low restriction, the “surplus fats” method is great for those seeking muscle but not yet ready to commit to a very rigid diet that disallows many common food choices.

Downsides of “Surplus Fats”

There are two clear downsides to gaining weight on the “surplus fats” approach:

1.) Loss of high carb effects

There are small but numerous benefits of a VERY high carb intake that are missed with using fats as surplus-generators. We’ll detail them later, but not having them is definitely a downside.

2.) Excess fats

Because most of the surplus is generated by fat intake, high levels of fats will be consistently coming out of the digestive (lymph) system and into the bloodstream on the “surplus fats” diet. Unfortunately, and as will be detailed later, excess fats that don’t get a chance to be used as fuel for muscle growth processes are VERY easily converted into stored fat, which means the “surplus fats” diet might cause a bit more fat gain than possible with other approaches.

Benefits of LCHF

There are three clear benefits to gaining weight on the LCHF approach:

1.) Fats easy for surplus

Fats are very easy to eat, are tasty, and have tons of calories (more than double protein or carbs) per gram. This means that getting to a high calorie level isn’t the end of the world when eating a high fat diet.

2.) Lower food volumes

Because fats are so calorie-dense, the amount of food that must be eaten to get to any certain calorie level is much less than with high-carb foods. This can be a godsend when hunger is all but gone deep into a massing phase and eating becomes a chore.

3.) Healthy fats and overall health

If you are going to overeat any nutrient, your health will suffer at least a little. It’s no hidden fact that gaining weight, be it muscle or fat, isn’t the path to longevity. That being said, of all the macros, fats are likely the least unhealthy to eat in a surplus. More particularly, health fats such as Omega-3’s and especially monounsaturated-heavy fat sources like nuts, nut butters, avocados, olive oils and canola oils have likely the lowest negative health impacts of all macros taken in excess. So if you want to gain weight but your health means the most to you, using mostly monounsaturated fats is likely a good choice.

Downsides of LCHF

There are six clear downsides to gaining weight on the LCHF approach:

1.) Low carb is hard on hyper

While in theory, those that WANT to gain weight on low carbs and high fats CAN, they don’t seem as likely to do so. In fact, if you feed most people a ketogenic (super low carb) diet and don’t restrict their calories, they actually end up eating LESS than maintenance! It takes serious willpower to smash that much low-carb food, so while gaining weight on low fats might be harder still, low-carb gaining is much, much harder than the “surplus fats” gaining of a mixed diet.

2.) Healthy fats vs. weight gain

In more than few studies, some kinds of healthy fats seem to be so satiating that they actually reduce the chances of weight gain. Almonds, for example, have been shown to NOT promote weight gain even when eaten freely. How come? Because how many raw almonds are you really gonna eat? Not many. And how much do they squash hunger? Seemingly in some situations, an amount proportional to the calories they bring in. So if you’re especially going to try to gain weight with mostly healthy fat consumption, you’ve got your work cut out for you
Further reading:

3.) Fat storage made simple

What do eaten fats need to be converted into before they are stored in fat cells if the conditions are right? Nothing… they come prepackaged as fats already and store very easily! Storing carbs and especially proteins as fats on the other hand requires quite a bit of biochemical conversion that is both a bit energy-taxing and just plain old less likely. Does this mean you gain no fat if your surplus is all carbs or all protein? No, but it does mean you gain a bit less. Which of course means that if your surplus is all fats… you gain fat at the highest possible rates per calorie ingested.

4.) Lower insulin

Does insulin help grow fat tissue? You bet. But it also helps to grow muscle tissue like crazy. With low carbs, insulin is down and a significant part of the muscle growth equation recedes. With high fats and low carbs, we end up being able to grow less muscle via insulin but the most fat possible via high fat intakes… not a good combo at all!

5.) Lower training energy

Remember that hard, high-volume training is required to potentiate muscle growth. With very low carbs, energy for just that sort of training will be reduced. This hurts the potential for muscle growth for sure.

6.) Lower glycogen

When the muscles have a high amount of glycogen, the sheer presence of it helps activate and facilitate muscle growth pathways in the cell. That’s right, training or just LIVING with high glycogen levels grows you more muscle per unit time… muscle you won’t grow as much of when the carbs to load that glycogen are nearly absent from your diet.
Further reading:

Benefits of HCLF

There are seven clear benefits to gaining weight on the HCLF approach:

1.) Insulin drive

Insulin is a big player in anabolism. While there isn’t much of a magic post-workout window for insulin, higher insulin levels throughout the day (and weeks and months of massing), combined with resistance training and proper protein intake, lead to more muscle growth. In fact, insulin likely interacts diurnally with growth hormone in such a way that the insulin secreted during daily eating preps the muscle cell to grow the most it can from its exposure to GH pulses at night. Either way you slice it, carbs secrete insulin and insulin makes you more jacked.
Further reading:

2.) Carbs stored as fat

As mentioned before, carbs don’t readily store as fat nearly as easily as fats do. Because you’re taking in excess SOMETHING anyway, that excess might as well be carbs because, though it’s by a small margin, those excess carbs are less likely to be stored and more likely to be burned.

3.) Guarantee on training energy

Even with an appropriate amount of carbs to your daily activity and training volume, you might not always be making use of the most carbs you can, just by sheer measurement error, whether that error is on the underestimating expenditure side or the overestimating intake side. By eating lots more carbs than you just need for training minimums, you nearly guarantee that fuel source will NOT be your limiting factor for hard training in the gym.

3b.) Pumps and growth?

It’s been shown that intracellular swelling likely causes some muscle growth. And how do you swell up the most? Catching a huge pump, of course! And with carbs, the more of them there are, the bigger the pump. Because the pump might actually itself grow muscle, this is no small matter. If you’re carbed-up nearly all the time, especially when you’re training, you’re likely growing more muscle than you otherwise would be if you were flatter.
Further reading:

4.) Rebound hunger for consistent eating

When smashing over 500g of carbs per day (and much more than that for larger athletes), you might start to err on the more quickly digested, higher glycemic carbs to just get them all in with each meal. Excess fiber doesn’t help, and of course your diet doesn’t allow much fat to really slow down digestion and absorption. A cool side benefit of this sped-up digestion is that you can “clear” a meal faster. Yep, the whole timeline of digesting a high protein and super high carb meal shrinks to lower than that of a mixed-meal that has fats in it, even calorie-equated. What this lets you do is eat more often, thus getting in more carbs, thus growing more! It takes serious work, but it can level the playing field a bit compared to the ease of eating on the “surplus fats” diet.

5.) Anabolism via glycogen

As mentioned, stored glycogen directly promotes muscle gain. The more carbs you eat on a daily basis, the higher your average glycogen stores will be and the higher your muscle growth rates will be.

6.) Anticatabolism of carbs

Carbs are POWERFUL anti-catabolic regulators. They are the preferred fuel source for most energy-consuming body processes, and if they are around in abundance, the body doesn’t really turn to burning muscle to meet energy needs nearly as much. The more carbs you take in, especially around your workouts (which tend to risk catabolism more than other conditions in your day) the more likely you are to prevent muscle loss and let muscle add up to higher amounts over time.

7.) Carbs vs. cortisol

Carbs directly reduce cortisol production. You may remember that cortisol is a stress hormone and is directly catabolic to muscle tissue. It also promotes fatigue when secreted, interferes with sleep, and is generally a negative for most recovery and adaptive processes. High carb eating means lower cortisol levels and all-around better recovery and adaptations to training, which for you will mean more muscle over time.

Downsides of HCLF

No approach is perfect, and there are three clear downsides to gaining weight on the HCLF approach:

1.) Oppressive food amounts

In order to get in enough calories to meet hypercaloric muscle-gain targets, a truly momentous amount of carbs must be consumed regularly, especially because high calorie fats are at such low values and cannot help much in generating a surplus. Eventually over the weeks of adding food as your metabolism on a mass phase speeds up, you get to what Broderick calls an “oppressive amount of carbs.” There’s only one way to eat enough food to grow with this approach, and that’s to eat often.

2.) High frequency eating

Yes, it’s possible get into the hypercaloric condition with low fats and high carbs, and yes, due to the rebound effect of consuming higher GI carbs and being ready to eat sooner due to their fast digestive clearance, there is a realistic way to do this. BUT, the high frequency eating that results is itself a huge pain in the ass, especially if you’re out and about and ESPECIALLY if you have to eat foods purchased on the go.

3.) Real world limitations

How many types of foods purchased on the go have high protein, high carbs, and very low fats? Not many! Low fat dieting with high carbs is very restrictive, and is especially so outside the home where you can take the time to prep your own macro-friendly foods.

On the net balance it seems like for the very dedicated, High Carb, Low Fat wins out on benefits vs. downsides, with “surplus fats” coming in at second place and LCHF coming in dead last. So where does the mix of practical and theoretical get us? Our formal position on the matter of fat intakes and anabolism is the following (taken from the upcoming RP Diet 2.0 book):

For beginners and intermediates, generating a calorie surplus with any of the three macros (proteins, fats, or carbs) is just fine so long as optimal intakes of proteins and carbs are being met (the “surplus fats” diet). Such is also the advice for individuals who very seriously struggle with eating enough food to gain weight, as for them more fats might make gaining easier. For more advanced trainers and those without problems eating, and especially those seeking to optimize their interventions, keeping fats close to their minimum values (0.3g per pound of body weight per day) while generating the hypercaloric condition with carbohydrate might be best practice.