Nutrient consumption and body mass index (BMI) are closely related to the gut microbiota, and exercise effects on gut bacteria composition may be related to those variables. Thus, we aimed to investigate the effect of 10-week moderate aerobic exercise on the cardiorespiratory fitness and gut bacteria composition of non-obese men with the same nutritional profile. Twenty-four previously sedentary men (age 25.18 [SD 4.66] years, BMI 24.5 [SD 3.72] kg/m²) were randomly assigned into Control (CG; n = 12) or Exercise Groups (EG; n = 12). Body composition, cardiorespiratory parameters, blood markers, dietary habits and gut bacteria composition were evaluated. EG performed 150 min per week of supervised moderate (60–65% of VO₂peak) aerobic exercise, while CG maintained their daily routine. The V4 16S rRNA gene was sequenced and treated using QIIME software. Only EG demonstrated marked improvements in cardiorespiratory fitness (VO₂peak, p < 0.05; Effect Size = 0.971) without changes in other gut bacteria-affecting variables. Exercise did not promote clustering based on diversity indices (p > 0.05), although significant variations in an unclassified genus from Clostridiales order and in Streptococcus genus were observed (p < 0.05). Moreover, α-diversity was correlated with VO₂peak (Pearson’s R: 0.47; R² 0.23: 95%CI: 0.09 to 0.74, p = 0.02) and BMI (Pearson’s R: −0.50; R² 0.25: 95%CI: −0.75 to −0.12, p = 0.01). Roseburia, Sutterella and Odoribacter genera were associated with VO₂peak, while Desulfovibrio and Faecalibacterium genera were associated with body composition (p < 0.05). Our study indicates that aerobic exercise at moderate intensity improved VO₂peak and affected gut bacteria composition of non-obese men who maintained a balanced consumption of nutrients.

The use of probiotics in sports has been growing in the past years focusing on the attenuation of upper respiratory tract (URS) and gastrointestinal (GI) symptoms commonly present in endurance athletes. Researches shown different results and this may related to the probiotic strain, dose, period consumption or even the form of administration (capsules, sachets or fermented milk). These four factors directly influence in the probiotic's outcome and this question still remains unclear. Thus, the goal of this review is to clarify how these factors may influence the outcomes, approaching the major differences among studies, mechanisms by which the probiotic may contribute in sports field and applied conclusions. It was used 'probiotics', 'athletes', 'sports', 'exercise', 'athletes performance', 'immune response', 'intestinal symptoms' as keywords and its combinations and 20 original articles were selected for our purpose. All the articles were performed in healthy physically active people and/or athletes. Putting together, it was observed that athletes may benefit from probiotics consumption. It seems that multi strain ingested via sachet or fermented food and a larger period of consumption may shown better results at minimizing URS and GI symptoms. Also, specific species appears to have a role in exercise recovery. Therefore, the beneficial effect of probiotics in sports field is strictly dependent on the four factors abovementioned. The molecular mechanisms behind the probiotics effectiveness have not yet been elucidated and perhaps the biological assessments performed in the studies as well the few number of studies published did not answer the question yet.

Introduction: Muscle injuries are common among elite athletes and compromise competitions and training schedules. Within the interventions to treat a sports injury, the nutritional approach is key to improve the physiological response and maintain the body composition to promote a quick and safe return to the play. Objective: Present an overview of the nutritional strategies and recommendations after a muscular sports injury, emphasizing the use of main nutrients and elements for the muscle recovery, such as proteins, antioxidants, omega 3 fatty acids, and probiotics. Methodology: The search of information was made in the PubMed, Science Direct, Scielo, Embase, and Google Scholar databases under specific DeCS and MeSh terms. The selected articles included literature reviews and clinical trials related to muscle injury in high-performance athletes, in any sports discipline or in immobilized patient (healthy men or women). Results: The stages of a muscle injury are classified as destruction-inflammation, repair, and remodeling phase. In all stages, energy recommendations should follow the estimated energy requirement plus the injury/stress percentage of increase (10–15%). During the repair phase, the optimal protein consumption (1.6–2.5 g/kg/day divided in several meals with 20–35 g of protein per meal) is crucial for muscle mass maintenance and to reduce the anabolic resistance of skeletal muscle in case of injury. Antioxidants intake from food sources may control the oxidative stress, which occurs during the inflammatory phase, as well as omega 3 fatty acids through stimulation of anti-inflammatory pathway. Moreover, probiotic consumption has been investigated in sports field with the goal of improving muscle repair by enhancing protein absorption capacity and immune cells function at the intestine. Conclusion: According to the literature, it is necessary to carry out clinical studies with injured athletes and determine how the consumption of nutrients and elements such as probiotics can influence the recovery processes of injured athletes. Also, there are little research in this area of sports nutrition.

The colonic epithelial cells represent a border between the colon luminal content, containing notably bacteria and a complex mixture of compounds, and the “milieu interieur” as defined by the French physiologist Claude Bernard. The physical-chemical composition of the luminal content, including luminal pH and bacterial metabolite, that obviously is not constant, is modified for instance according to the diet. Data obtained recently indicate that physical exercise may also modify the colonic luminal content. Evidence has indicated that modification of the luminal content characteristics has, indeed, consequences for the colonic epithelial cells, notably in terms of energy metabolism and DNA integrity. Although such alterations impact presumably the homeostatic process of the colonic epithelium renewal and the epithelial barrier function, their contribution to pathological processes like mucosal inflammation, pre-neoplasia, and neoplasia remains partly elusive. Open questions remain regarding the individual and collective roles of luminal changes, particularly in a long-term perspective. These questions are related particularly to the capacity of the bacterial metabolites to cross the mucus layer before entering the colonocytes, to the concentrations of metabolites in proximity of the colonic crypt stem cells, and to the capacity of colonocytes to detoxicate deleterious compounds, to take up and utilize beneficial compounds.

Obesity alters the capacity of effective immune responses in infections. To further address this phenomenon in the context of COVID-19, this study investigated how the immunophenotype of leukocytes was altered in individuals with obesity in severe COVID-19. This cross-sectional study enrolled 27 ICU COVID-19 patients (67% women, 56.33 ± 19.55 years) that were assigned to obese (BMI ≥ 30 kg/m², n = 9) or non-obese (BMI < 30kg/m², n = 18) groups. Monocytes, NK, and both Low-Density (LD) and High-Density (HD) neutrophils were isolated from peripheral blood samples, and surface receptors’ frequency and expression patterns were analyzed by flow cytometry. Clinical status and biochemical data were additionally evaluated. The frequency of monocytes was negatively correlated with BMI, while NK cells and HD neutrophils were positively associated (p < 0.05). Patients with obesity showed a significant reduction of monocytes, and these cells expressed high levels of PD-L1 (p < 0.05). A higher frequency of NK cells and increased expression of TREM-1+ on HD neutrophils were detected in obese patients (p < 0.05). The expression of receptors related to antigen-presentation, phagocytosis, chemotaxis, inflammation and suppression were strongly correlated with clinical markers only in obese patients (p < 0.05). Collectively, these outcomes revealed that obesity differentially affected, and largely depressed, innate immune response in severe COVID-19.

Background: Triggering receptor expressed on myeloid cells-1 (TREM-1) has emerged as an important inflammatory marker of immune response associated with severity and mortality outcomes in infection diseases, including viral pneumonias. Aim: (1) To evaluate the expression of TREM-1 in patients with COVID-19 and other viral pneumonias compared to healthy individuals; and (2) to analyze the levels of these biomarkers according to disease severity. Method: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Searches were performed in PubMed, Scopus, Embase, and Google Scholar. Studies were considered eligible if they were observational studies that provided data on the levels of TREM-1 in humans with viral pneumonia compared to healthy controls. The results of the meta-analysis were expressed as standardized mean difference (SMD) and an effect size of 0.8 was considered a large effect. A subgroup analysis was performed according to the disease severity. Results: Seven studies were included in this systematic review. Four studies included patients with COVID-19 and three analyzed patients with different viruses. The meta-analysis was performed only with patients with COVID-19, which showed increased levels of soluble form of TREM-1 among patients with COVID-19 compared to healthy controls (SMD 1.53; 95% CI 0.53 to 2.52; p < 0.01). No differences were found between patients with mild to moderate COVID-19 and healthy controls, but higher levels of sTREM-1 were shown among patients with severe COVID-19 (SMD 1.83; 95% CI 0.77 to 2.88; p < 0.01). All three studies evaluating including patients with other viral pneumonias showed that TREM-1 levels were significantly elevated in infected patients compared with controls. Conclusion: These findings may provide evidence on the pro-inflammatory role of TREM-1 in these infections, contributing to the inflammatory profile and disease progression.