Effects of a Lactobacillus salivarius probiotic intervention on infection, cold symptom duration and severity, and mucosal immunity in endurance athletes

摘要

The purpose of this study was to examine the effects of a probiotic supplement during 4 mo of spring trainingudin men and women engaged in endurance-based physical activities on incidence of upper respiratory tractudinfections (URTI) and mucosal immune markers. Sixty-six highly active individuals were randomized toudprobiotic (n = 33) or placebo (n = 33) groups and, under double-blind procedures, received probiotic (PRO:udLactobacillus salivarius, 2 × 1010 bacterium colony-forming units) or placebo (PLA) daily for 16 wk. Restingudblood and saliva samples were collected at baseline and after 8 and 16 wk. Weekly training and illness logsudwere kept. Fifty-four subjects completed the study (n = 27 PRO, n = 27 PLA). The proportion of subjects onudPRO who experienced 1 or more wk with URTI symptoms was not different from that of those on PLA (PROud.58, PLA .59; p = .947). The number of URTI episodes was similar in the 2 groups (PRO 1.6 ± 0.3, PLA 1.4 ±ud0.3; p = .710). Severity and duration of symptoms were not significantly different between treatments. Bloodudleukocyte, neutrophil, monocyte, and lymphocyte counts; saliva IgA; and lysozyme concentrations did notudchange over the course of the study and were not different on PRO compared with PLA. Regular ingestionudof L. salivarius does not appear to be beneficial in reducing the frequency of URTI in an athletic cohort anduddoes not affect blood leukocyte counts or levels of salivary antimicrobial proteins during a spring period ofudtraining and competition.