Background. Although Lactobacillus casei Shirota (LcS) can benefit the immune status, the effects of LcS in the immune/inflammatory responses of marathon runners has never been evaluated. Therefore, here we evaluated the effect of daily ingestion of fermented milk containing or not LcS in the systemic and upper airway immune/inflammatory responses before and after a marathon. Methods. Forty-two male marathon runners ingested a fermented milk containing 40 billion of LcS/day (LcS group, n = 20) or placebo (unfermented milk, n = 22) during 30 days pre-marathon. Immune/inflammatory parameters in nasal mucosa and serum, as well as concentrations of secretory IgA (SIgA) and antimicrobial peptides in saliva, were evaluated before and after fermented milk ingestion, immediately, 72 h, and 14 d post-marathon. Results. Higher proinflammatory cytokine levels in serum and nasal mucosa, and also lower salivary levels of SIgA and antimicrobial peptides, were found immediately post-marathon in the placebo group compared to other time points and to LcS group. In opposite, higher anti-inflammatory levels and reduced neutrophil infiltration on nasal mucosa were found in the LcS group compared to other time points and to the placebo group. Conclusion. For the first time, it is shown that LcS is able to modulate the systemic and airways immune responses post-marathon.

Immunosenescence is associated to aging and among many changes in immune response is reported a reduced response to vaccination and an increase in the number of cases of autoimmunity, caused by autoantibodies known as natural antibodies whose function, according to reports, would be protection against infection and inflammation. Although immunosenescence is an irreversible process, regular moderate exercise can attenuate some aspects of the decline in the immune system. So, the aim of this study was to investigate the humoral immune response in physically active elderly individuals before and 30 days after vaccination against influenza virus. The results showed that the percentage of individuals positive for antinuclear antibodies and serum immunoglobulin M and G levels after vaccination were higher in the group that exercised regularly than in the sedentary group. We were also able to demonstrate a significant correlation between levels of natural autoantibodies and response to vaccination.

Nowadays, it is accepted that the regular practice of exercise and branched-chain amino acids supplementation (BCAAs) can benefit the immune responses in older persons, prevent the occurrence of physical frailty (PF), cognitive decline, and aging-related comorbidities. However, the impact of their combination (as non-pharmacological interventions) in albumin and the inflammatory markers is not fully understood. Therefore, we investigated the effect of a 40-week multifactorial intervention [MIP, multicomponent exercise (ME) associated or not with BCAAs] on plasma levels of inflammatory markers and albumin in frail older persons (≥75 years old) living at residential care homes (RCH). This study consisted of a prospective, naturalistic, controlled clinical trial with four arms of multifactorial and experimental (interventions-wahshout-interventions) design. The intervention groups were ME + BCAAs (n = 8), ME (n = 7), BCAAs (n = 7), and control group (n = 13). Lower limb muscle-strength, cognitive profile, and PF tests were concomitantly evaluated with plasma levels of albumin, anti- and pro-inflammatory cytokines [Interleukin-10 (IL-10) and Tumor Necrosis Factor-alpha (TNF-α) respectively], TNF-α/IL-10 ratio, and myeloperoxidase (MPO) activity at four different time-points: Baseline (T1), after 16 weeks of multifactorial intervention (T2), then after a subsequent 8 weeks washout period (T3) and finally, after an additional 16 weeks of multifactorial intervention (T4). Improvement of cognitive profile and muscle strength-related albumin levels, as well as reduction in the TNF-α levels were found particularly in ME plus BCAAs group. No significant variations were observed over time for TNF-α/IL-10 ratio or MPO activity. Overall, the study showed that MIP triggered slight alterations in the inflammatory and physical function of the frail older participants, which could provide independence and higher quality of life for this population.

The new coronavirus (SARS‐CoV‐2) appearance in Wuhan, China, did rise the new virus disease (COVID‐19), which spread globally in a short time, leading the World Health Organization to declare a new global pandemic. To contain and mitigate the spread of SARS‐CoV‐2, specific public health procedures were implemented in virtually all countries, with a significant impact on society, making it difficult to keep the regular practice of physical activity. It is widely accepted that an active lifestyle contributes to the improvement of general health and preservation of cardiovascular, respiratory, osteo‐muscular and immune system capacities. The positive effects of regular physical activity on the immune system have emerged as a pivotal trigger of general health, underlying the beneficial effects of physical activity on multiple physiological systems. Accordingly, recent studies have already pointed out the negative impact of physical inactivity caused by the social isolation imposed by the public sanitary authorities due to COVID‐19. Nevertheless, there are still no current narrative reviews evaluating the real impact of COVID‐19 on active lifestyle or even discussing the possible beneficial effects of exercise‐promoted immune upgrade against the severity or progression of COVID‐19. Based on the consensus in the scientific literature, in this review, we discuss how an exercise adherence could adequately improve immune responses in times of the ‘COVID‐19 Era and beyond’.