Leucine and sprint times in basketball players
What it found
In 20 male basketball players, taking leucine for 28 days shortened a 282-foot sprint time by about 1.2 seconds compared with placebo.
Other performance measures and wellbeing ratings improved slightly but not enough to be statistically significant.
What they found
Studies in people
Sprint performance
Sprint times dropped from 17.4 to 16.2 seconds in the leucine group, while the control group changed only from 17.3 to 17.1 seconds. This difference was statistically significant.
Shooting accuracy
Three-point field goals and free throws improved slightly in the leucine group but not enough to be statistically significant. The control group showed minimal changes.
Wellbeing ratings
Self-rated mental and physical wellbeing during practice increased from 7.3 to 7.9 in the leucine group, compared with a small rise from 7.1 to 7.3 in the control group. This difference was not statistically significant.
Gene activity in muscle
Muscle samples showed 3,658 genes with different activity between the groups. These genes were involved in immune response, cytokine production and neutrophil extracellular trap formation.
Cytoskeleton genes
A gene module linked to muscle growth was enriched in cytoskeleton pathways. Lab tests confirmed that leucine increased the activity of several cytoskeleton-related genes, including tubulins, keratins, vimentin, cofilin, gelsolin, profilin, MAPs and cadherins.
What the authors conclude
“These results suggest that leucine enhances muscle adaptation by regulating cytoskeletal dynamics, providing molecular insights into its role in improving athletic performance.”
Also in their conclusions
- They conclude that leucine supplementation improved exercise performance, particularly by significantly reducing sprint times and showing trends of improvement in other performance metrics.
- They state that these results suggest leucine enhances muscle adaptation by regulating cytoskeletal dynamics, providing molecular insights into its role in improving athletic performance.
- They advise that future studies should consider longer durations, larger cohorts, and additional performance measures to comprehensively assess leucine's benefits.
How it was done
The authors wanted to understand the molecular mechanisms behind leucine's reported benefits for athletic performance, which remain unclear. They focused on basketball players because this sport demands explosive power and endurance.
They recruited 20 male university basketball players aged 18 to 23 and randomly split them into two groups. For 28 days, one group drank a functional drink with leucine (50 mg per kg body weight per day) and the other had a placebo. Before and after, they measured sprint times, free throws, three-point shots and self-rated wellbeing. Muscle samples were taken from the biceps for gene analysis.
What it can’t tell you
- This was a small study of 20 male basketball players, so the results may not apply to other groups or sports.
- The study lasted only 28 days, so it cannot show what happens with longer use.
- The gene activity findings come from muscle samples taken after supplementation and cannot prove that leucine directly caused the changes.
Who paid
- Conflicts
- The authors have declared that no competing interests exist.
- Authors work at
- Sejong University, Korea; Jeonbuk National University, Korea; Pingdingshan University, China
The paper
- Title
- Unraveling the transcriptomic effects of leucine supplementation on muscle growth and performance in basketball athletes
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Wang S, Guo W, Dong R (2025). Unraveling the transcriptomic effects of leucine supplementation on muscle growth and performance in basketball athletes. PloS one. doi:10.1371/journal.pone.0316603Free full textPubMed 39854288DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error