Prevalence, Severity and Potential Nutritional Causes of Gastrointestinal Symptoms during a Marathon in Recreational Runners

Abstract

The purpose of the present study was to investigate the prevalence of gastrointestinal symptoms (GIS) amongst recreational runners during a marathon race, and potential nutritional factors that may contribute. Recreational runners of the 2017 Liverpool (n = 66) and Dublin (n = 30) marathons were recruited. GIS were reported post-marathon and we considered GIS in the 7 days prior to the marathon and during the marathon using the Gastrointestinal Symptom Rating Scale (GSRS). Nutritional intake was recorded using food diaries for the day before the race, morning of the race, and during the race; 43% of participants reported moderate (≥4) GIS in the 7 days prior to the marathon and 27% reported moderate symptoms during the marathon with most common symptoms being flatulence (16%) during training, and nausea (8%) during the marathon race. Correlations between all nutritional intake and GIS were not statistically significant (p > 0.05). There were significant correlations between total GIS score (r = 0.510, p < 0.001), upper GIS score (r = 0.346, p = 0.001) and lower GIS score (r = 0.483, p < 0.001) in training and during the marathon. There appears to be a modest prevalence of GIS in recreational runners, in the week prior to a marathon and during marathon running, although there was no association with nutritional intake before or during the race.

Heat alleviation strategies for athletic performance: A review and practitioner guidelines

“…Metabolic adaptations (albeit reported in nonelite populations) include; lowered metabolic rates, reduced rates of glycolysis associated with a reduction in the relative intensity of exercise [54], and improved muscle contractility [55]. Heat adaptation is associated with elevated heat shock proteins (HSPs) with acute and chronic elevations in HSPs supporting/facilitating heat adaptation [56] and maintaining epithelial tight junctions in the gut, mitigating gastrointestinal distress when an athlete competes in the heat [57,58] and attenuating circulating precursors to heat illness [59]. With the athlete in mind, at a cellular level, the induction of heat adaptation via short-and medium-term HA does not appear to impact circulating markers of immune function negatively [60][61][62][63].…”

“…L-glutamine has also been implicated as an important amino acid in facilitating elevations in HSPs, and in maintaining gut function under heat stress [200][201][202]. These proteins have been evidenced as important in attenuating gastrointestinal (GI) permeability during heat stress which may improve symptoms of gastrointestinal distress [57,58], heat-related illness [59], and facilitating heat adaptation in general via HSPs [56]. Though proposed as beneficial, as yet, probiotic intake has not been evidenced as beneficial during repeated exercise in the heat [203].…”

Four weeks of probiotic supplementation reduces GI symptoms during a marathon race

“…Gastrointestinal (GI) symptoms are widely reported in athletes participating in prolonged endurance events (Costa et al 2017a ). In marathon running, 27% of recreational runners report moderate or more severe GI symptoms during a race (Pugh et al 2018 ). The pathogenesis of such symptomology is still poorly understood, although it is likely multifactorial in nature.…”

“…However, due to the range of symptom types (each with their own unique aetiology) coupled with differences in study methodologies to assess GI symptoms, studies to date have yet to find a single mechanism. Nonetheless, GI symptoms during marathon running remain detrimental to exercise performance in recreational and elite runners (Pugh et al 2018 ) hence potential strategies to reduce such remains an attractive area of research.…”

Longitudinal Analysis of Marathon Runners’ Psychological State and Its Relationship With Running Speed at Ventilatory Thresholds

“…Overall, in agreement with the existing literature (e.g., Bandura, 1994), medium-term improvements in perceived fitness, self-efficacy and motivation were associated with improvements (decreases) in anxiety, although the effects were predominantly small. However, we found a shift in somatic anxiety from day-32 to day-11 that has been already linked to training load-derived stress (Rehm et al, 2013), and it is also associated with alterations of the immune system, as well as commonly referred gastrointestinal symptoms (Pugh et al, 2018). Interestingly, the increase in somatic anxiety during the last assessment happened in absence of a significant increase in cognitive anxiety (worries).…”