Branched-chain amino acids are all the rage these days, even though their benefits have long been known: They increase energy, blunt fatigue, drive muscle growth, aid fat loss, boost brain power, and even extend life. The three BCAAs are leucine, isoleucine, and valine. Leucine is the MVP when it comes to boosting muscle protein synthesis, particularly after exercise. Valine is the MVP before workouts, as it's directly responsible for blunting fatigue via a mechanism in the brain. Isoleucine, another essential amino acid (like the other two BCAAs), is involved in muscle tissue repair and may even help increase energy levels.

In other words, it's not enough just to supplement with leucine. You need all three BCAAs to maximize the benefits.



Here's how to use BCAAs to their maximum effect to get the best gains in muscle size—and the greatest bang for your supplement buck.

The Best Ratio of BCAAs

It's critical not only to get ample amounts of all three BCAAs but also to get them in the proper ratio. Your best bet is a 2-1-1 ratio of leucine to isoleucine to valine. So, 6 grams of BCAAs should provide about 3 grams of leucine and 1.5 grams each of isoleucine and valine. The highest you ever want to go would be a 3-1-1 ratio, particularly post-workout, when leucine is driving muscle protein synthesis. Any greater ratio would have too little valine and isoleucine.

Use but Don't Abuse

All too often you see bodybuilders walking around with a gallon jug containing water mixed with a flavored BCAA supplement. They sip on it all day to provide their muscles with a constant trickle of BCAAs, in hopes that it will stop muscle breakdown and increase muscle protein synthesis and, therefore, muscle growth.

Sadly, this technique will have the opposite effect and actually can prevent spikes in muscle protein synthesis. Research shows that you need to cycle your intake of BCAAs, having a couple hours in between doses, to create a true spike in muscle protein synthesis. When leucine is available in the bloodstream 24/7, it prevents the MPS spikes that come only after a couple of hours of low blood leucine levels.

How do you cycle BCAA intake to maximize all results? Use my priority list below and take your BCAAs only at these times. Whatever you do, stop sipping on them all day long, unless your goal is steady energy throughout the day. That's the only true benefit that constantly sipping BCAAs will provide.

Use but Dont Abuse

BCAA Priority List

  • Priority 1: Boosting Energy for Workouts
  • Timing: Approximately 30 minutes before workouts

The most critical time to get a 6-10-gram dose of BCAAs is before workouts. The reason is that BCAAs are unlike any other amino acids. They don't need to go to the liver first; they can go directly to the muscle cells, where they're used for fuel.

  • Priority 2: Driving Muscle Recovery and Growth
  • Timing: Within 30 minutes after workouts

The next most critical time to take 6-10 grams of BCAAs is after workouts. Here, it's important to get leucine to the muscle cells, where it can activate the protein kinase mTOR and push muscle protein synthesis as well as muscle growth.



  • Priority 3: Spiking Muscle Protein Synthesis between Meals
  • Timing: 2 hours after meals

When you eat a meal that includes at least 3 grams of leucine and at least 30 grams of protein, muscle protein synthesis is spiked momentarily. About two hours after the meal, protein synthesis will have dropped, but the amino acids from the meal are still in the bloodstream. At this time, if you provide another 3 grams of leucine (as well as the other two BCAAs), it may create a second spike in muscle protein synthesis from that same meal.

  • Priority 4: Bumping Up the Leucine Content of a Meal
  • Timing: With meals that don't provide at least 30 grams of protein

As mentioned, you need at least 30 grams of a complete protein, as well as a good 3 grams of leucine, to maximize muscle protein synthesis. If a meal provides less than 30 grams of protein, it likely also doesn't provide a full 3 grams of leucine. To create a bigger spike in protein synthesis from this meal, you can take a 6-10-gram dose of BCAAs to ensure that the leucine content is high enough to do it.

Where to Get Your BCAAs

Each serving of Pre JYM and Post JYM (active matrix) provides 6 grams of BCAAs in the proper ratio of leucine to isoleucine to valine. That means you can take either product (depending on your caffeine tolerance and needs) to get your BCAAs, along with additional ingredients like creatine, beta-alanine, betaine, taurine, and glutamine (Post JYM only).

If you want to save those products just for pre-workout and post-workout, you can also use a stand-alone BCAA product—like my brand-new JYM BCAAs product, available exclusively here at Bodybuilding.com. JYM BCAAs includes the ideal 2:1:1 ratio of leucine to isoleucine to valine. I created JYM BCAAs to provide ultimate flexibility in taking BCAAs throughout the day, whether pre-workout, post-workout, between meals, or with meals that don’t deliver adequate leucine (i.e., meals containing fewer than 30 grams of protein through quality sources like chicken, beef, and eggs).

For more articles on nutrition and supplementation, as well as workouts and training tips, visit JimStoppani.com.

About the Author

Jim Stoppani, Ph.D.

Jim Stoppani, Ph.D.

Jim Stoppani holds a doctorate in exercise physiology from the University of Connecticut and has been the personal nutrition and health consultant to numerous celebrity clients, including...

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