Laura Lewis, MS
While many athletes have different preferences for when to take amino acids, evidence from several studies suggests that the best time to take amino acids is directly before a workout. This timing seems to best support muscle synthesis, integrity, and recovery.* It also likely supports resilience during physical activity, as well as healthy muscle recovery.*
A popular amino acid complex to take before a workout are BCAAs, or branched-chain amino acids. BCAAs include three essential amino acids—leucine, isoleucine, and valine. We call them essential amino acids because the body cannot synthesize them, but they are important for normal bodily function.* BCAAs in particular make up nearly 35% of the amino acids present in muscle tissue.
While BCAAs are present in food and protein supplements, they can sometimes take too long to process to achieve full benefits during a workout.* That’s why taking BCAAs 30 minutes prior to a workout is usually an athlete’s preference.
4 Reasons to Take Amino Acids Before a Workout
1 – Supports Cellular Energy*
In a study published in the Journal of Nutrition, researchers found that the oral intake of BCAAs prior to a workout may increase an uptake in the essential amino acid tryptophan and reduce the synthesis and release of serotonin, which may enhance resilience and sustained energy.* [1]
Another reason these BCAAs may support physical stamina is because during a workout, your body breaks down BCAAs to use as an energy source. If you’re planning on a more intense or longer workout, taking a BCAA supplement beforehand may prime you with more BCAAs to be able to train more intensely and for a longer period of time.* [2]
2 – Enhances Muscle Synthesis*
During a workout, both your muscle breakdown and muscle synthesis systems activate. Post-workout, your muscle breakdown exceeds muscle synthesis until the essential amino acid leucine is present. This is because leucine activates mTOR which supports protein synthesis and normal muscle tissue growth.* [3]
When you already have an increase of BCAAs in your body from taking amino acids prior to your workout, leucine is primed and ready to help your muscles recover post-workout.*
Some people think this means that you should take your BCAAs directly after the workout, but a study by the Department of Surgery, University of Texas Medical Branch, showed as much as a 2.5X increase in phenylalanine uptake when an oral essential amino acid-carbohydrate supplement was taken pre-workout as opposed to post-workout. The study suggested that net protein synthesis is greater when amino acids were consumed before exercise compared to after a workout.* [4]
3 – Healthy Muscle Recovery*
While extensive studies have not yet been performed, early tests suggest that taking amino acids before a workout can support healthy muscle recovery as much as 20%.* In this double-blind study, 12 young, healthy, untrained female participants ingested either BCAA or a placebo prior to a squat exercise. Two days after the exercise, the BCAA trial reported significantly less soreness than the placebo trial. This study also suggested that BCAAs may support muscle integrity.* [5]
4 – Supports Healthy Muscle Tissue*
In multiple tests, results suggested that taking BCAAs prior to a workout enhances muscle tissue integrity.* During these studies, participants showed a decrease in serum concentrations of creatine kinase (KS) and lactate dehydrogenase (LDH).* These chemicals are indicators of muscle damage. These studies showed that even when the recommended intake of BCAA was already present in regular diet, taking BCAAs prior to the workout significantly decreased the post-exercise values of these enzymes.* [6]
Final Thoughts
There is still much to discover about the fascinating science of amino acids. But, the early research suggests that taking amino acids 30-60 minutes prior to a workout can significantly increase their benefits.*
Remember to always consult a healthcare professional prior to any diet or exercise program and before beginning any dietary supplement. This article is not intended to diagnose or serve as medical advice; it is only intended to provide informational resources.
Disclaimer:
The information provided is for educational purposes only. Consult your physician or healthcare practitioner if you have specific questions before instituting any changes in your daily lifestyle including changes in diet, exercise, and supplement use.
Laura Lewis is a clinical researcher and science communicator with a Master of Science degree and a background in nutrition science and integrative health. She brings a decade of experience translating complex clinical data into accessible insights for healthcare practitioners and patients alike.
Laura has contributed to educational programming and strategic content development across the integrative and functional medicine space. Her strengths lie in evidence synthesis, practitioner engagement, and crafting communications that bridge the gap between scientific rigor and real-world application. At ARG, Laura supports clinical content development and educational initiatives that elevate practitioner confidence and product credibility.