Effect of a Probiotics Supplementation on Respiratory Infections and Immune and Hormonal Parameters during Intense Military Training

Abstract

This study examined the effect of a probiotics supplementation on respiratory tract infection (RTI) and immune and hormonal changes during the French Commando training (3-week training followed by a 5-day combat course). Cadets (21 +/- 0.4 years) received either a probiotics (n = 24) or a placebo (n = 23) supplementation over the training period. We found no difference in the RTI incidence between groups but a significantly greater proportion of rhinopharyngitis in the probiotic group (p < 0.05). Among immune parameters, the major finding was an immunoglobulin A decrease after the combat course only in the placebo group (p < 0.01), but the difference between the two groups was not significant. A greater increase in dehydroepiandrostane sulfate was observed in the probiotics group after the combat course (p < 0.05). This study suggested that the benefits of a probiotics supplementation in a multistressor environment relied mainly on its capacity to prevent the infection to spread throughout the respiratory tract.

Daily Probiotic’s (Lactobacillus casei Shirota) Reduction of Infection Incidence in Athletes

“…A few recent probiotic intervention studies in athletes have provided evidence of apparent health benefit, with reports of fewer days of respiratory illness and lower severity of respiratory-illness symptoms (Cox et al, 2010;West, Pyne, Hopkins, et al, 2009) and shortened duration of GI-upset episodes (Kekkonen et al, 2007) when taking a daily Lactobacillus probiotic. Possible mechanisms appear to include higher spontaneous IFN-γ production (Cox et al, 2010) and improved maintenance of salivary IgA levels (Tiollier et al, 2007) during periods of physical stress. West, Pyne, Hopkins, et al (2009) recently reported that probiotic supplementation (L. fermentum) in a cohort of 64 male and 35 female elite endurance athletes was associated with a lower symptom load for chest infections and less use of cold and flu medications in males taking the probiotic compared with placebo, although differences in clinical outcomes between females in the two groups were not evident.…”

Probiotics for the prevention of respiratory tract infections: a systematic review

“…Among the 14 included RCTs, 6 involved healthy children or infants [31,33,35,38,43,44], 6 involved healthy adults [32,34,36,37,39,41], an additional one involved children with a RTI [40] and the remaining RCT involved adults with a RTI [42]. Notably, 3 of the 14 included RCTs studied specific populations, which were healthy male cadets taking part in intense military training [34], free-living elderly subjects (>60 years of age) [41] and healthy marathon runners [32].…”

“…Outcomes regarding the prevention, severity and duration of RTIs as well as the adverse events attributed to study treatments are also presented in Table 1. Among the 14 included RCTs, 11 had a double-blind design [31][32][33][34][35][36][37][38][39]42,44], 2 were open-label RCTs [40,41], whereas the remaining RCT did not provide data regarding blinding [43]. The probiotic preparations were compared with matching placebo or with no treatment.…”

“…The probiotic preparations were compared with matching placebo or with no treatment. Nine of the fourteen included RCTs were assigned a Jadad score >2 [31][32][33][35][36][37][38][39]44], whereas three RCTs [34,40,42] and two RCTs [41,43] were assigned a Jadad score of 2 and 1, respectively.…”

“…Among these, 14 individual RCTs were regarded as qualifying for inclusion in this review [31][32][33][34][35][36][37][38][39][40][41][42][43][44]. The detailed process of the selection of eligible trials is depicted graphically in Fig.…”