Protein is made up of amino acids. There are essential amino acids (ones we need to get from our diet), and non-essential ones (ones our body can make on its own).
Branch-chain amino acids (BCAAs) are the most important amino acids in the muscle-building process. However, the other amino acids are still needed, so if you’re struggling to meet your daily protein intake needs from real food (see my macro calculator), you should supplement with protein powder, not BCAAs.
Not all protein powders are equal for muscle building. Whey has the “best” amino acid profile because it has the highest in BCAA content. So, choose a whey powder when buying protein.
If you do your weight training early in the morning without having eaten anything prior (people refer to this as “fasted training”), it is advisable to take a scoop of whey protein prior to training to minimize muscle breakdown.
Up until the end of 2017, I recommended BCAA supplementation to clients who trained fasted. However, a significant amount of research has come out since that question the benefit of BCAAs, and I have changed the recommendations I give to clients to whey instead.
This article explains my reasoning for this and the protocols I recommend for both the whey and BCAA supplementation.
Why Whey Protein Is Better Than BCAAs When Training Fasted
Before reading further, the underlying assumption is that you have your diet set up to support your goals in the first place. If you aren’t consistently eating an appropriate number of calories, an adequate quantity of protein, carbs, and fats, you’re suffering chronic micronutrition shortages because you lack fruits and vegetables in your diet, and you’re ignoring the basics of meal timing, then the question of BCAAs vs Whey is entirely irrelevant. You have bigger issues. Here’s my nutrition setup guide which will teach you how to fix them.
The Origin of The Recommendation To ‘Drink BCAAs When Training Fasted’
Many of my clients are high achievers with demanding jobs. The majority choose to train early in the morning before the working day zaps their energy and motivation to train. They do not have any time to consume (and start to digest) a meal before training.
This leaves them, potentially, without any amino acids (the building blocks of protein) in circulation in their bloodstream from digested food earlier in the day, when they train. Without the necessary amino acids in the bloodstream to start the repair process, the body is forced to break down muscle into amino acids, which is not what we want.
This is where BCAA supplementation comes in as a recommendation. As the most important amino acids for muscle building, a BCAA powder can be consumed easily before training and absorbed quickly.
Typically, people who choose to train fasted in the morning would consume a 20 g dose of BCAAs split before and after their workout, with those that train very early in the morning consuming an additional 10 g due to the longer time until their lunch. This part of Martin Berkhan’s ‘Leangains’ protocol for his clients that train in the morning which I chose to adopt for my clients myself in the past.
As you can see from the client results, this has worked well. But, these results may have been even better if they had used whey protein.
Why Whey is More Anabolic Than BCAAs or EAAs
To maximize muscle growth we need to:
- Optimize the signal for muscle protein synthesis (MPS) by consuming enough leucine (one of the BCAAs),
- Consume enough amino acid building blocks to actually synthesize new proteins (muscle).
As my friend Menno Henselmans likes to say, “Consuming just BCAAs for MPS is like turning on a light switch when there’s no power supply. You can flip the switch all you like, but you won’t get any light (MPS) without electricity (other amino acids).”
So, BCAAs alone cannot maximize muscle growth.
With whey, we get the rest of the essential amino acids (EAAs) plus other anabolic/anti-catabolic co-factors that are missing in isolated BCAA, such as lactoferrin, beta-lactoglobulin, alpha-lactalbumin, glycomacropeptide, and immunoglobulins (hence its ability to support immune function).
Whey also has antioxidant, antihypertensive, antitumor, hypolipidemic, antiviral, and antibacterial properties. You’d also be hitting the acute dosing ceiling for muscle protein synthesis with a full scoop.
In summary, taking whey protein costs less and we get a stronger anabolic response.
BCAA vs Whey: Comparing by Caloric Values
Contrary to what many products have on their labels, the free-form BCAA powders that we buy are not calorie free. They have a caloric value of 4.65 kcal/g, which means the typical 10 g serving has 46.5 calories.
Geeky details: Leucine and isoleucine each have a gross energy of 6.52 kcal/g; valine has 5.96 kcal/g when protein bound. The metabolizable energy is slightly lower, 6.18 kcal/g and 5.55 kcal/g respectively.
However, the free-form energy values in the BCAA powders we buy are 4.65 kcal/g, 4.65 kcal/g and 4.64 kcal/g for each of the three BCAAs respectively. Here’s the paper from where these numbers are derived.
So, why can manufacturers get away with not listing this on the packet you ask?
Because of a loophole in the FDA regulations. One states that supplement manufacturers can’t declare the protein content of a product when this only contains individual amino acids. Another allows supplement manufacturers to calculate the caloric content of their products using a number of methods, including the Atwater method, which involves adding up the calories from protein (4 kcal/g), carbs (4 kcal/g) and fats (9 kcal/g). Therefore, they aren’t required to list the calories. Shady shit, but to be expected from supplement manufacturers.
Though products vary, a standard commercial mix of whey concentrate and isolate (Optimum Nutrition Gold Standard Whey) has 120 kcal listed with 24 g protein per scoop.
Comparing the average BCAA formula with the average whey protein, we get the following:
10 g BCAA = 46.5 kcal = 0.37 scoop of whey = 9.3 g protein
20 g BCAA = 93 kcal = 0.77 scoop of whey = 18.6 g protein
30 g BCAA = 139.5 kcal = 1.16 scoop of whey = 27.9 g protein
Fasted Training Supplementation Protocol Recommendations
Best Option: Whey protein
Take a scoop of whey (the equivalent of 25 g of protein) around 30 minutes prior to working out. Then take another scoop every 3 hours after that until your first meal of the day. Depending on your whey protein brand, this may be 30-35 g of powder.
Count this against your protein and calorie targets for the day.
Whey is a milk-derived protein powder. It is fairly low in lactose, but if you have issues, or if you are a vegan, consider buying a custom blend 70:30 mix of pea and rice protein. This closely mimics the amino acid profile of whey.
Second-best Option: EAAs
The nine essential amino acids (EAAs) are available in powder form like BCAAs and likely a little better.
Take 10 g of EAAs, (1 small scoop mixed in a 500 ml water bottle) 10 minutes before your weight lifting workouts. Take 10 g of EAAs every 2-2.5 hours thereafter until your first meal of the day.
Because they have a caloric value, for every 10 g of EAAs you consume, reduce your calorie intake by 50 kcal, by reducing your fat or carb intake (not your protein intake).
So, let’s say that you take 30 g of EAAs, that’s ~150 kcal you need to remove from your diet. This can be achieved by reducing your carb intake by 35 g, fats by ~15 g, or a mix of both.
Third-best Option: BCAAs
Take 10 g of BCAAs, (1 small scoop mixed in a 500 ml water bottle) 10 minutes before your weight lifting workouts. Take 10 g of BCAAs every 2-2.5 hours thereafter until your first meal of the day.
Because they have a caloric value, for every 10 g of BCAAs you consume, reduce your calorie intake by 50 kcal, by reducing your fat or carb intake (not your protein intake).
So, let’s say that you take 30 g of BCAAs, that’s ~150 kcal you need to remove from your diet. This can be achieved by reducing your carb intake by 35 g, fats by ~15 g, or a mix of both.
Fasted Training and BCAA vs Whey FAQ
Whey protein is better than just taking BCAA. Whey protein is 25% BCAA. The key difference is that with whey, we get the rest of the essential amino acids (EAAs) plus other anabolic/anti-catabolic co-factors missing in isolated BCAA.
Whey protein is 25% BCAAs, so you do not need to take BCAAs if you take whey. If you have a diet high enough in protein, you do not need to take whey protein either because BCAAs are present in the foods we eat. However, taking whey is better than training completely fasted if you train early in the morning.
BCAA powders are not worth buying. Many studies have decisively shown that supplementing BCAAs on top of sufficient dietary protein intake does not improve our gains in any way.
If you are looking for a supplement to buy to help you reach your daily protein targets, whey protein costs less than BCAAs, and you get a stronger anabolic response.
BCAAs, particularly leucine, are important for optimizing the signal to build muscle, but you need the rest of the amino acids to actually build muscle. BCAAs make up 16-25% of the protein sources we typically eat (fish, meat, whey powder), so there is no need to supplement them.
Supplementing with BCAA alone would be like getting the construction workers on a building site fired up to work for the day, then not giving them any materials to build with.
BCAAs are an incomplete protein, not as anabolic as whey alone. Therefore, I would not count the BCAAs against your protein targets for the day, but subtract them from the other macronutrients (carbs and fats).
Hydrolyzed whey is similar to whey isolate, but the protein has gone through a process called “enzymatic hydrolysis,” which makes it faster to digest. It’s significantly more expensive, so unless you have less than 30 minutes between your alarm and the time you’re lifting something heavy, I wouldn’t bother.
Whey concentrate has a slightly lower quantity of protein and typically a few more carbs per scoop, compared with isolate. Often, whey isolate isn’t worth the extra cost.
Whey and casein are both high-quality protein types (meaning they have an amino acid profile high in BCAAs). The difference is primarily in the rates of absorption, which will be significantly slower for the casein. As we want the amino acids to be in the bloodstream as quickly as possible when training fasted, whey protein is the best option.
In both situations, you are no longer training fasted. Yes, BCAAs have a caloric value, but some manufacturers do not list it on the label. (This is something that caught me off guard for a long time also.)
If you want to train truly fasted, then you need to drink only water prior to training, which is simply not optimal. Why? Because what we are seeking to do here is minimize muscle breakdown during workouts (and promote growth, when possible).
Break your fast or break (down) your muscles. Choose wisely.
A 70:30 mix of pea and rice protein closely mimics the amino acid profile of whey. It is possible to order custom blends from some stores online.
I asked him to take a look at this before publishing to see if I had missed anything. He said it ‘looks good.’
Completely useless, assuming that you are consuming an adequate amount of protein in your diet daily in the first place. If you are not, the best course of action is to eat more protein, not supplement with BCAAs.
Feel free to keep paying for this expensive, high-calorie, flavored drink that is costing you other food options in your daily caloric budget if you prefer.
That’s the caffeine in that BCAA product you are using (take another look at the label), some added arginine (or citrulline malate) causing your skin to tingle, or just a placebo effect.
When it runs out, just switch. The difference is likely there, but marginal.
No. Fasted cardio won’t amount to the kind of stimulus where you’ll risk significant muscle breakdown, like with an intense resistance training workout.
That’s fine, these are just guidelines for those clients who find it easier to train first thing in the morning before the working day zaps their energy.
Thank you for reading. Questions welcomed in the comments.