Do you really need carbs to build muscle on a primal diet?
Now, this is a primal blog, so technically we should only weight train for 30 minutes twice a week, otherwise, we’ll stress ourselves too much and be in a constant state of overtraining. While this is a great approach for some, others like to be a little more hardcore. CrossFit anyone? We all know about numerous benefits of weight training, from improved bone density to increases in overall health and longevity. But let’s be honest here. Some of us just want to achieve an aesthetically pleasing athletic body with toned legs, perky butts, rounded shoulders, and V-tapered backs. Whatever the reason for building muscle, many probably wonder if it’s possible to achieve while on a lower carb primal diet.
So here is the thing, we’ve all probably heard that a typical diet of a bodybuilder (and if these guys know anything at all, it would be how to build muscle) consists of really high protein, insane amounts of carbs (sometimes upward of 500g a day!) and very low fat. Well, you know carbs and protein increase muscle synthesis and fat make you, well, fat. Or so the bodybuilding community has thought for decades. Could this possibly be wrong?
How do muscles contract?
Let’s start with the basics.
The main “currency” that provides energy for muscular contraction is ATP – adenosine triphosphate. This is the only thing that the muscle uses directly to contract, not protein, not carbs, not fat, just ATP. To be even more precise, the energy is actually stored in a phosphate (P) bond. So think of it this way – whatever has P is in a higher energy, more activated state. This applies to many biological molecules, including enzymes. You can see in the diagram that once ATP loses one of its 3 Ps, it becomes ADP. Thus it has less energy to give to cellular functions. Your own ATP stores will only last for about 1 second of maximal contraction. So now you need to either regenerate ATP by getting that lost P from somewhere or make new ATP altogether.
The quickest way to get P is to steal it from creatine phosphate – CrP (yes, creatine doesn’t only come in a powdered form from your local supplement store, you have it in your muscles!). And that’s exactly what happens in your muscle cells until you run out of CrP which happens fairly quickly – in about 4 seconds of maximal contraction.
Now, all this stuff will be regenerated to some degree in between contractions, but let’s face it, most of us perform a contraction/rep for longer than 5 seconds. So where do we get more ATP?
The next step is to release some glucose from glycogen (both adrenaline and glucagon facilitate the process) and make ATP from it through glycolysis (literal decomposition of glucose). Eventually liver starts to output glucose into the bloodstream as well to be used by muscle. Other fuels, such as free fatty acids from blood and intramuscular fat also come into play. For the purpose of this article, we’ll focus on glucose from muscle glycogen.
So here is where the carbs come in or, to be more precise, the misconception about them. Glycogen is a storage form of glucose in muscles and liver. According to basic science, we need glucose to sustain muscular contraction. It has been concluded that we need to eat lots of carbs on daily basis to keep our glycogen stores full for our next workout session. This is not really the case. If you eat about 50-100g of carbohydrates a day, it will easily keep liver glycogen stores full and make some of the muscle glycogen as well.
Carbohydrates and glycogen stores
You see, carbohydrates are not an essential nutrient. Your body will make glucose out of non-carbohydrate sources such as lactate (and you thought it was just a waste product causing a burning sensation in your muscles), glycerol (from fat) and glycogenic amino acids that mainly come from protein you consume through diet. Even if you are on a ketogenic diet, your body will refill some those glycogen stores in your muscles. Numerous studies have shown that after 2-8 weeks on a high-fat diet (70% fat) there is a decrease in liver and muscle glycogen content. But also there is an increased contribution of fat to oxidative metabolism at the same relative intensity level.
And the cool part is that the adaptations last even after a high carbohydrate consumption for 2 days to replenish glycogen stores. Once you become fat-adapted, fatty acids are utilized more during lower intensity activities, sparing glycogen for that weight training session. In a nutshell, you become more efficient at using fat for fuel and saving glycogen for when you really need it. These adaptations are highly individual, and you’ll have to figure out for yourself the perfect amount of carbs. But it’s best to keep carbs under 150g a day to keep inflammation down.
When not to eat your carbs
The timing of carbs you do consume matter when it comes to muscle building. Many sources suggest eating some carbs before a workout. However, this will cause insulin – a storage hormone – to spike, shutting down the release of free fatty acids from your body’s fat stores. As a result, you can’t use them for energy and – the obvious – lose body fat.
Protein is key
In order to build muscle, the net protein balance (synthesis – degradation = net protein balance) should be positive most of the time. In order to achieve it, we need to consume an adequate amount of protein. Keep in mind that both breakdown and synthesis are always taking place. Whichever predominates determines whether we build muscle or lose it. Weight training does throw net protein balance towards negative. It happens simply because there is a significant muscle fiber damage happening during a heavy weight training session.
What’s important is your post-workout nutrition. Research has shown that ingestion of amino acids after resistance training session results in a significant positive net protein balance. Which means you are making more new protein than you are breaking down. What’s interesting is that some studies have compared the effect of just amino acid ingestion post training to that of amino acid and carbohydrate mixture ingestion. There was absolutely no difference in net protein balance! When participants ingested carbohydrates alone or took insulin, the breakdown of protein was decreased but there was no increase in synthesis. So, contrary to popular belief, you really don’t need carbs after a workout, only amino acids.
What about glycogen stores?
Although we can easily train and build muscle on a low carb diet, incorporating some “refeed” days may be beneficial to get muscle glycogen stores full every now and then. As noted above, a couple of higher carbohydrate days a week should not throw you out of fat-adaptation. Remember, if you want to keep inflammation low, it’s best to stay under 150g.
How to build muscle without carbs on Primal:
• Become fat-adapted so you can access your body fat storage to be used for fuel
• You don’t need carbs before or after your workout to increase muscle synthesis, but you do need amino acids. Invest into a good quality BCAA supplement.
• Implement 1 or 2 “refeed” days a week with carbohydrate intake increasing up to 150g/day, depending on personal goals and tolerance levels.
This article was kindly written by Maria Duval. Maria Duval is a Certified Primal Health Coach and founder of www.fit-treat.com where she helps women achieve the best physique possible while maintaining optimal health and reversing aging. She combines her formal medical background with a BS in Exercise Science and over 10 years of experience in nutrition and bodybuilding.