The Study
Acute effects of combined supplementation of L-arginine and citrulline malate on aerobic, anaerobic, and CrossFit exercise performance
This study is like a fair test where two teams tried the same workout—one team took a supplement and the other took a fake pill. The results showed almost no difference, except one tiny thing: the supplement group reached their top speed a little faster. But we can't say for sure the supplement caused that, because the test wasn't big enough to be super sure.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave trained men a drink with two amino acids before they did intense workouts to see if it made them stronger or faster.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 571 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Faster time to peak power means you reach your max speed quicker, but since max speed itself didn't increase, it's like hitting the gas pedal sooner—not going faster overall.
- 2They got faster to reach their top speed in a 30-second bike sprint (by 40%), but didn't pedal harder or longer.
- 3No improvement in CrossFit or cardio tests.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Scientific Reports
Year
2025
Authors
Saranya Selvaraj, L. Petridis, Hanna Majtényi, Henrietta Bartha, Ákos Tóth, Katinka Utczás, M. Szilágyi-Utczás, Rachel Kimble, Reza Zare, Arash Akbari, Katie M. Heinrich
Related Content
Claims (5)
In trained men, taking L-arginine and citrulline malate before a 30-second all-out cycling test reduces the time it takes to reach maximum power by about 40%, but does not increase the highest power or average power achieved.
Taking one dose of L-arginine and citrulline malate does not change how quickly the heart recovers or how long endurance lasts during the Harvard Step Test in trained men.
Taking L-arginine and citrulline malate supplements leads to a quicker reach of maximum power during a short, intense cycling test, but it does not result in higher maximum or average power output, suggesting the effect is restricted to the timing of power development.
Taking a single dose of 0.15 grams per kilogram of L-arginine and 0.1 grams per kilogram of citrulline malate does not improve aerobic endurance, anaerobic power, or CrossFit performance in healthy, trained men.
Taking L-arginine and citrulline malate before the CrossFit 'Cindy' workout does not change performance in trained men, even though performance improves over repeated test sessions due to practice.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.