Introduction: To examine how different weekly training and competition schedules influence gut microbiota composition in elite volleyball players, investigating the relationship between training and competition demands, recovery periods and microbial dynamics to identify potential biomarkers for training load and recovery status assessment.Methods: Seven elite athletes from the Italian Men's SuperLega Championship (age: 26.5 ± 4.5 years; weight: 96 ± 11 kg; height: 200 ± 0.1 cm; BMI: 24 ± 1.9) were monitored at four timepoints over eight weeks Regular Season periods (T0, T1), Rest Period (T2) and International Tournament Period (T3). Faecal samples underwent 16S rRNA sequencing analysis, with concurrent Mediterranean Diet adherence and Stool Consistency assessments. Repeated measures ANOVA and one-way ANOVA were performed to evaluate microbial abundance changes.Results: 16S rRNA sequencing revealed Firmicutes predominance (41.22–76.03%), followed by Actinobacteria (9.66–54.45%) and Bacteroidetes (0.73–26.56%). The Firmicutes/Bacteroidetes ratio fluctuated in response to training intensity and competition 6:1 during T0 and T1, decreasing to 3:1 during T2 and returning to 5:1 during T3. Dominant bacterial families included Ruminococcaceae (26.97–28.3%), Bifidobacteriaceae (17.46–22.92%) and Lachnospiraceae (9.66–12.61%). Significant enrichment of Rikenellaceae abundance occurred during Rest Periods (p < 0.05). α-Diversity remained stable despite individual variation. Mediterranean diet adherence declined during Regular Season Periods (T0: 6.3 ± 1.5, T1: 5.5 ± 0.8), while stool consistency gradually improved.Discussion: Despite overall stability, elite athletes gut microbiota adapted to volleyball varying training demands primarily via Firmicutes/Bacteroidetes ratio modulations and Rikenellaceae enrichment during Recovery Periods. These microbial alterations represent potential biomarkers for assessing training load and recovery status. Additional investigation is necessary to elucidate how these microbial dynamics influence athletic performance outcomes.

Introduction: The gut microbiome represents a key ecosystem influencing athletic performance through energy metabolism modulation, inflammatory response regulation, and recovery optimization in high-level athletes. However, the relationship between performance and gut microbiome composition in high-level athletes remains poorly understood.Objectives: This systematic scoping review aims to map the current evidence on the relationship between training and gut microbiome in high-level athletes, identify specific patterns in microbial response to different training and sports, analyse the effects of nutritional interventions and highlight some methodological and knowledge gaps in the current literature.Methodology: Following the PRISMA-ScR framework, a systematic search was conducted on PubMed, Scopus and Web of Science (2015-2025). Studies were selected according to defined criteria, including a population of high-level athletes, interventions through training and/or nutritional protocols and based on outcomes related to performance and health.Results: Nineteen studies met the inclusion criteria, comprising 12 experimental studies and 7 systematic/narrative reviews. The analysis of the studies revealed possible sport-specific patterns in microbiome modulation, with distinctive alterations in metabolic profiles, significant correlations between microbial stability and athletic performance, synergistic effects between training and probiotic supplementation and significant impacts of nutritional strategies and hormonal contraceptives on microbiome composition. The heterogeneity in analysis methodologies and the limited duration of studies emerge as the main limitations of the present study.Conclusions: The evidence suggests that the significant role of the gut microbiome in athletic performance optimization may be considered in the future, highlighting the importance of implementing an integrated approach between training and nutrition. Further studies are needed to define specific microbiome trends for different types of sports, competition levels and supplementation targeted at implementing performance outcomes in high-level athletes.Systematic Review Registration: https://osf.io/yh49t, identifier YH49T.

The gut microbiota represents a complex microbial ecosystem with the potential to influence athletic performance, energy metabolism, inflammatory responses, and recovery capacity in athletes. However, the specific relationship between microbiota and performance in combat sport athletes remains poorly characterized. This scoping review systematically maps current evidence on gut microbiota-combat sports performance relationships, identifies microbial response patterns to training and competition, evaluates nutritional prebiotic and probiotic interventions, and highlights methodological gaps to guide future research. Following the PRISMA-ScR framework, 8 studies were identified, which included 247 elite and high-level athletes, comprising 169 males and 78 females, with sample sizes ranging from 12 to 53 across wrestling, mixed martial arts, martial arts, judo, and taekwondo. Associations were observed between gut microbiota characteristics and training intensity, competition level, weight management, and pre-competition psychological states. Limited taxonomic consistency was observed across studies, with most bacterial genera appearing in a single investigation, precluding the identification of robust sport-specific microbial signatures. Preliminary trials demonstrated improvements in gastrointestinal symptoms, aerobic performance, and psychological fatigue with prebiotic and probiotic interventions. However, small sample sizes and methodological heterogeneity across studies limit generalizability and preclude definitive conclusions regarding the role of gut microbiome in combat sports performance.

Purpose: This review examines the bidirectional interactions between gut microbiota and the brain, with a specific focus on their implications for sport performance. The main research question addresses how gut-brain communication responds to physical activity and actively contributes to athletic performance in elite athletes subjected to high physiological demands. Methods: A comprehensive review was conducted analysing the characteristics and development of gut microbiota, the methods used to investigate microbiota-brain interactions and the bidirectional communication pathways. The analysis distinguished the two directions of interaction brain-induced effects on microbiota and microbiota-induced effects on brain activity, with specific integration into sports contexts. Results: The review identified that gut-brain communication constitutes a dynamic system that responds to physical activity through multiple pathways. Elite athletes, subjected to high-intensity training regimens, specialized nutritional approaches and specific performance goals, exhibit distinctive microbiota conditions. Brain-derived neurotrophic factor (BDNF), serotonin and butyrate emerged as key mediators that contribute to adaptive gut microbiota conditions and facilitate microbiota-brain interactions. Conclusion: The microbiota-gut-brain axis represents a fundamental system actively contributing to sport performance. The interdisciplinary evidence from neuroscientists, microbiologists, nutritionists and sports scientists demonstrates that understanding these interactions opens new frontiers for optimizing athletic performance through targeted modulation of this bidirectional communication system.

Article: The role of the hormonal profile of constitutional biotypes in the training process - Medicina dello Sport 2023 September;76(3):343-52 - Minerva Medica - Journals

The growing interest in the role of the gut microbiome in athletic performance has led to the application of various sequencing technologies in this field. This review critically examines the sequencing methodologies used in microbiome studies on physical performance and sport, comparing their advantages, limitations, and applicability. In particular, the focus is on 16S metabarcoding and shotgun metagenomics, evaluating how these methodological approaches influence the interpretation of results in sports contexts. Close attention is directed toward technical challenges, methodological biases, and future perspectives, including emerging technologies and multi-omics approaches. This review aims to bridge the gap between methodological rigor and sports-specific applicability, providing evidence-based methodological guidance to support researchers in designing robust athlete microbiome studies and translating sequencing-derived findings into concrete applications for performance and sports health.