The Frequency and Severity of Gastrointestinal Symptoms in Rugby Players

This study aimed to assess the self-reported frequency and severity of gastrointestinal symptoms (GIS) at rest and around rugby training and match play in male and female rugby union players. An online questionnaire was sent to registered rugby union players (sevens or fifteens). Thirteen GIS were assessed alongside perceptions of appetite around rugby and rest using Likert and visual analog scales. Questions investigating a range of medical and dietary factors were included. Three hundred and twenty-five players (male n=271, female n=54) participated in the study. More frequent GIS (at least one GIS experienced weekly/more often) was reported by players at rest (n=203; 62%) compared to around rugby (n=154; 47%). The overall severity of GIS was low (mild discomfort), but a portion of players (33%) did report symptoms of moderate severity around rugby. Female players reported more frequent and severe symptoms compared to male counterparts (p<0.001). Self-reported appetite was significantly lower after matches compared to training. There were no dietary or medical factors associated with GIS severity scores. This study describes GIS characteristics in male and female rugby union players. Half of the players assessed experienced some form of GIS that may affect nutrition, training, or performance, and should thus be a consideration for practitioners supporting this cohort.

Exercise and associated dietary extremes impact on gut microbial diversity

OBJECTIVE

The commensal microbiota, host immunity and metabolism participate in a signalling network, with diet influencing each component of this triad. In addition to diet, many elements of a modern lifestyle influence the gut microbiota but the degree to which exercise affects this population is unclear. Therefore, we explored exercise and diet for their impact on the gut microbiota.

DESIGN

Since extremes of exercise often accompany extremes of diet, we addressed the issue by studying professional athletes from an international rugby union squad. Two groups were included to control for physical size, age and gender. Compositional analysis of the microbiota was explored by 16S rRNA amplicon sequencing. Each participant completed a detailed food frequency questionnaire.

RESULTS

As expected, athletes and controls differed significantly with respect to plasma creatine kinase (a marker of extreme exercise), and inflammatory and metabolic markers. More importantly, athletes had a higher diversity of gut micro-organisms, representing 22 distinct phyla, which in turn positively correlated with protein consumption and creatine kinase.

CONCLUSIONS

The results provide evidence for a beneficial impact of exercise on gut microbiota diversity but also indicate that the relationship is complex and is related to accompanying dietary extremes.