Protective Effects of Probiotics on Runners' Mood: Immunometabolic Mechanisms Post-Exercise.

Background: The gut-brain axis may mediate mood changes due to strenuous exercise. Therefore, probiotic supplementation may mitigate mood worsening.

Purpose: The present study aims to evaluate the effect of probiotic supplementation on mood and immunometabolic parameters after a marathon.

Materials and methods: Fourteen marathon runners were selected and divided into placebo and probiotic groups that were supplemented for 30 days. Before and after the marathon, mood (POMS) was assessed, and blood was collected for analysis of immunometabolic parameters. Statistical analysis was performed, and p < 0.05 was considered to determine statistically differences.

Results: Tension decreased after the marathon in both groups. Vigor decreased only in the placebo group. Fatigue increased after the marathon in both groups. TMD increased after the marathon in placebo. The IL2/IL-4 ratio decreased in the probiotic group after the marathon compared to before and increased compared to the placebo group. The IL-10 increased after the marathon in placebo. TNF-α increased after the marathon in probiotics. The TNF-α/IL-10 ratio decreased after the marathon in both groups. LPS decreased in the probiotic group after the marathon compared to before and in the placebo group.

Conclusions: Thirty days of probiotic supplementation attenuated the impact of marathons on mood worsening. The decrease in LPS in the probiotic group mediated the change in the pro/anti-inflammatory balance, indicating an immunometabolic mechanism by which the gut-brain axis impacts mood after strenuous exercise.