International SportMed Journal - Volume 6, Issue 3, 2005
Volume 6, Issue 3, 2005
The gastrointestinal system : the relationship between an athlete's health and sport performance : review articleSource: International SportMed Journal 6, pp 130 –140 (2005)More Less
Gastrointestinal (GI) problems are frequent in endurance athletes. The prevalence of such symptoms has been reported to be 30-50% among marathon runners. These GI problems occur more in running sports in comparison to activities with lower mechanical strain, such as cycling or swimming, where the vertical movement is limited. This observation suggests the theory that mechanical irritation could be one possible mechanism. <br>Furthermore, diminished perfusion of the splanchnic vessels during exercise, secretion of gastrointestinal hormones and other substances, as well as disturbed absorption, have been identified as being responsible for these symptoms. <br>In addition, external factors may be involved. As total body water is lost during exercise, sufficient rehydration is mandatory, especially in endurance activities, or during heat exposure. The choice and amount of fluid (containing carbohydrates and/or minerals) may modify the complaints. Nutrition itself may further contribute to gastrointestinal complaints, and considering the possible goals of an adequate nutrition may not only diminish these complaints but also lead to an improvement and maintenance of the athlete's health. <br>However, despite the high prevalence of these complaints, their aetiology in endurance athletes is still not fully understood. This article reviews possible pathophysiological interrelationships and therapeutic approaches to these GI symptoms.
Clinical investigation of athletes and gastrointestinal symptoms : where is the starting line? : review articleSource: International SportMed Journal 6, pp 141 –150 (2005)More Less
The majority of athletes experience gastrointestinal symptoms either during or shortly after exercise. Moreover, physical activity is known to have profound effects on gastrointestinal functions in athletes, which may be caused by physiological adaptations. Organ damage may be induced either by overstrenuous exercise or underlying gastrointestinal diseases, and the differential diagnosis usually requires comprehensive medical investigations. <br>The aim of this article is to review and evaluate diagnostic investigations in athletes presenting with gastrointestinal symptoms. These symptoms are determined by the type and intensity of the exercise, as well as age, gender, training status and dietary factors. Endurance athletes are most commonly affected, and their clinical presentation ranges from mild symptoms, such as heartburn or diarrhoea, to severe manifestations of acute gastrointestinal diseases, including acute abdominal pain and haematochezia. Clinical, biochemical, functional and endoscopic diagnostic procedures are therefore guided by the nature and history of symptoms, as well as their temporal relationship to exercise. <br>In conclusion, medical investigations are indicated when symptoms persist after periods of rest, and when they are severe or life-threatening. Diagnostic algorithms do not radically differ in athletes and non-athletes, but physiological changes and adaptations to exercise must be considered during medical investigations.
Source: International SportMed Journal 6, pp 151 –161 (2005)More Less
Physical activity has become popular in our sedentary society. Gastrointestinal (GI) symptoms are common during exercise among well-trained athletes and joggers. <br><I>Objective:</I> The aim of the present review is to summarise the current knowledge of the mechanisms behind the changes of gastrointestinal function during exercise. <br><I>Data sources:</I> The electronic databases of PubMed and SPORTDiscus were searched for original research articles and literature reviews using the terms exercise, physical activity, gastrointestinal function and gastrointestinal tract. Searches of the library catalogue for older articles and reviews were also performed. <br><I>Study selection:</I> Journal articles, abstracts and books containing relevant information about exercise and gastrointestinal function were reviewed and selected. <br><I>Data extraction:</I> From these investigations and other data sources the analysed variables and the main outcomes were examined. <br><I>Data synthesis and conclusion:</I> The effects of physical activity on the gastrointestinal tract were categorised by logical groupings of similar mechanisms. In the reviewed articles there is general consensus that exercise has probably both beneficial and harmful effects on the GI tract, depending partly on the training effect. The reasons behind these somewhat discrepant effects are not understood fully. Altered splanchnic blood flow, effects on GI motor function, neuroendocrine changes, and mechanical effects are mainly involved. There is probably a considerable linkage between these suggested mechanisms; however, more studies are needed to understand the relationship between exercise intensity and duration, and positive and negative alterations in GI physiology.
Source: International SportMed Journal 6, pp 162 –170 (2005)More Less
This article reviews the literature of gastrointestinal (GI) problems in runners. These problems commonly affect runners and some believe that they can hamper performance. Many physiologic processes, including the interplay of decreased transit time, absorptive effects, hormonal changes, and endotoxins breaching the bowel wall contribute to an incomplete understanding of the physiology behind the pathology. Upper GI pathology, such as gastroesophageal reflux disease (GERD), nausea, and vomiting, can detract from the pleasurable aspects of running, while gastritis, hepatitis and pancreatitis can threaten the health of the athlete. Lower GI pathology, such as diarrhoea and colitis, can similarly taint the runner's experience. The authors examine various pathologies suspected of contributing to runner's anaemia, the side stitch, and the effect of running on previous GI pathology. Also discussed are important elements of history, physical examination, and treatments.
The effect of walking training on respiratory function and performance in older females : original research articleSource: International SportMed Journal 6, pp 171 –184 (2005)More Less
<I>Background:</I> Sarcopenia affects respiratory system function, potentially decreasing thoracic cavity pressure development and exercise performance. <br><I>Research question:</i> To investigate the role of walking training on reductions in respiratory muscle strength which are conceivably due to aging. <br><I>Type of study:</i> Randomised control study. <br><I>Methods:</I> Twenty-six older females (range: 60-69 yrs) were assessed for respiratory function, respiratory muscle strength and walking performance. Thirteen participants were then randomly assigned to a walking training group (WT) for eight weeks and were required to undertake three supervised walking sessions per week at 60% of the heart rate reserve value. Sessions ranged from 20 to 40 minutes duration. <br><I>Results:</I> Following the training, the amount of change in respiratory muscle strength was superior in the WT group in comparison to the control group (9% for inspiratory and expiratory strength, p<0.05). Further, the WT group demonstrated an improvement in treadmill walking performance of 11% (p< 0.05), whilst treadmill walking performance for the controls remained unchanged. Despite such improvements, there were no changes to respiratory variables measured at three submaximal velocities during the treadmill assessment. <br><I>Conclusions:</I> The improvement in respiratory muscle strength indicates the strong involvement of the respiratory system during walking training; however, the lack of change in respiratory variables during submaximal walking indicates that the respiratory system may not be an exercise limiting factor in 60-69 yr-old females during submaximal tasks. In contrast, at elevated walking intensities, the improved strength of the respiratory muscles may assist in a greater tolerance of the required workload.