The Claim

Three weeks of daily L-glutamine supplementation at 0.3 g/kg body weight in combat-sport athletes is associated with improved subjective mood scores and has no significant effect on muscle soreness, sleep quality, or perceived stress.

Source: Supplementation of L-glutamine enhanced mucosal immunity and improved hormonal status of combat-sport athletes

What the research says

Challenges is higher

Challenge is ahead, but a single strong supporting study can change this.

Supports
0score
Challenges
54score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In combat-sport athletes taking 0.3 grams of L-glutamine per kilogram of body weight daily for three weeks, subjective mood scores improve, while muscle soreness, sleep quality, and perceived stress remain unchanged.

See the scientific wording

Three weeks of daily L-glutamine supplementation at 0.3 g/kg body weight in combat-sport athletes is associated with improved subjective mood scores, though it does not significantly affect muscle soreness, sleep quality, or perceived stress.

Why this might work

L-glutamine reduces gut leakage during intense training, which lowers systemic inflammation. This prevents the stress hormone cortisol from rising too high and helps maintain testosterone levels. The balanced ratio of these hormones supports brain function and emotional state, leading to better mood.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Supplementation of L-glutamine enhanced mucosal immunity and improved hormonal status of combat-sport athletes

    The study found that athletes who took a placebo felt better emotionally than those who took L-glutamine, which is the opposite of what the claim says. So, the study actually contradicts the idea that L-glutamine improves mood.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.