If you’re into working out, sports nutrition supplements like BCAAs (or branched-chain amino acids) probably play a part in your fitness routine. After all, supplements that contain these aminos are some of the most popular in the training world.
That said, navigating BCAAs can be a little tricky. Check out the labels of many BCAA powders and you’ll find a line or two boasting about the product’s “2:1:1” BCAA ratio. Not sure what that means—and why it matters? Here, experts explain.
What Are BCAAs?
If you’re still not quite clear on what the BCAAs are (and what they do in your body to support your workouts), let’s get that straight first.
There are 20 amino acids that make up the many proteins in your body. Nine of those amino acids are known as “essential amino acids” because you can only get them through food and supplements. The rest, your body can produce on its own.
Let’s drill down even further. Three of those nine essential amino acids—leucine, isoleucine, and valine—are known as the BCAAs. This trio has been shown to have a unique ability to help with muscle building and physical performance.
“BCAAs may serve as an energy source during a workout, slowing the breakdown of muscle protein,” says sports dietitian Natalie Rizzo, M.S., R.D., founder of Greenletes. “They also help your body build muscle after a workout.” Because BCAAs are absorbed more quickly than other amino acids, they can get into your muscle tissues ASAP, according to Nutrition and Enhanced Sports Performance.
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Leucine, for one, helps stimulate muscle protein synthesis (the process of rebuilding protein to repair muscle damage), produces growth hormones, contributes to regulating blood sugar levels, and prevents the breakdown of muscle proteins after trauma or stress. This is the BCAA that tends to get the most credit for repairing and rebuilding your muscles after a workout.
Meanwhile, isoleucine plays a key role in immune function, building hemoglobin (the red blood cell protein that carries oxygen), and keeping blood sugar and energy levels steady.
Valine, finally, assists with muscle growth and tissue repair, muscle coordination, energy, and even keeping your emotions in check.
So What’s A 2:1:1 BCAA Ratio?
Now that we’ve got that out of the way, onto this whole BCAA ratio thing. When you see the term “2:1:1” written on a BCAA supplement, that means the product contains two grams of leucine for every one gram of isoleucine and one gram of valine, Rizzo says.
“[The 2:1:1] ratio has been shown to enhance muscle protein synthesis, as well as increase energy and reduce fatigue during exercise,” says Kristen Arnold, M.S., R.D., a board-certified specialist in sports dietetics.
Here’s why the specific 2:1:1 ratio works:
While all of the BCAAs play important roles, leucine is truly “the powerhouse BCAA for muscle growth,” Arnold says. That’s why it’s the “2” in that “2:1:1” ratio. “To accelerate muscle protein synthesis post-exercise, it is important to have a higher proportion of BCAAs from leucine than isoleucine and valine,” she explains.
So why not, say, 10:1:1 if leucine’s so special? For starters, the 2:1:1 ratio has the most research to back it up, says Dawn Jackson Blatner, R.D., a board-certified specialist in sports dietetics.
Plus, if you get too leucine-happy with your supplement blend, you ultimately sacrifice isoleucine and valine content, Blatner adds. In some cases, these levels may be lowered so much that you don’t reap optimal benefits. For example, a five-gram scoop of a 2:1:1 BCAA powder would offer three grams of leucine, 1 gram of isoleucine, and 1 gram of valine. Go up to a 10:1:1 powder and you’ll get 4.2 grams of leucine but only 0.42 grams of isoleucine and 0.42 grams of valine, explains Blatner.
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You may be wondering: But if leucine is the key BCAA for muscle growth, does it really matter how much isoleucine and valine I get? It does.
“Leucine is the amino acid that starts the whole process of building muscle, like a key in the ignition starts the car, but research suggests you need the other two BCAAs to get full results because leucine by itself isn’t as powerful for energy, muscle recovery, and blood sugar regulation,” Blatner notes.
The Bottom Line
There’s a good reason that brands boast about a 2:1:1 ratio on their BCAA products, so it’s definitely worth looking for when shopping for your next go-to supplement. A few popular options that include this gold standard combo: BodyTech Elite Ultimate BCAA, Alani Nu BCAA (which also happens to be vegan), and Evlution Nutrition BCAA Energy.