# The Effect of Acute Supplementation of Branched Chain Amino Acids on Serum Metabolites During Endurance Exercise in Healthy Young Males: An Integrative Metabolomics and Correlation Analysis Based on a Randomized Crossover Study

## TL;DR

This study shows that short-term BCAA supplementation in young males improves fat oxidation and reduces exercise-induced muscle damage markers.

## Contribution

The study provides new insights into the metabolic effects of acute BCAA supplementation during endurance exercise using integrative metabolomics.

## Key findings

- Acute BCAA supplementation enhanced fat oxidation and reduced post-exercise ammonia, creatine kinase, and lactate dehydrogenase levels.
- Metabolomics revealed changes in lipid, amino acid, and glucose metabolism pathways, particularly fatty acid oxidation and tryptophan-related pathways.
- Correlation analysis linked BCAA intake with improved fat oxidation and ammonia clearance.

## Abstract

Background: Branched-chain amino acids (BCAAs) are popular as sports supplements due to their ability to enhance performance and recovery. However, the full spectrum of metabolic alterations triggered by acute supplementation with BCAAs in conjunction with exercise remains incompletely understood. Methods: A randomized crossover trial was conducted in 8 healthy active young males, who received either BCAA or placebo supplementation for three consecutive days prior to a high-intensity cycling test. Plasma samples were collected pre- and post-exercise and analyzed by ultra-high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry, followed by correlation and enrichment analyses. Results: Acute BCAA supplementation was significantly associated with enhanced fat oxidation and attenuated post-exercise increases in plasma ammonia, creatine kinase, and lactate dehydrogenase, suggesting the potential improvements in energy supply and membrane stability. Metabolomics analysis identified differential metabolites primarily involved in lipid, amino acid, and glucose metabolism. Pathway enrichment revealed coordinated regulation of fatty acid oxidation (FAO) and tryptophan-related pathways. Correlation analysis further showed that changes in metabolite profiles were strongly associated with biochemical outcomes, particularly linking enhanced fat oxidation and ammonia clearance with BCAA intake. Conclusions: Short-term BCAA supplementation could enhance FAO and membrane stability via coordinated regulation of lipid and amino acid metabolism post exercise, supporting its potential role as a precision nutrition strategy.