The colon

Symptoms attributed to the effects of exercise on the colon are the most commonly reported and seem to be most frequent among runners [33]. 'Nervous' diarrhea (43%), defecation with running (62%), diarrhea during racing (47%), diarrhea associated with severe cramps, rectal bleeding (16%) and even fecal incontinence (12%) were reported in a runners' club survey [34]. While symptoms are common, colonic physiology during exercise is obscure, conflicting and difficult to analyse. Probes are difficult to place and maintain during exercise. Motion artifact is more prominent and transit time is measured in many hours instead of minutes. No change in fecal transit time was found when measured by radioisotope markers in a controlled metabolic laboratory during a 9-week training period [35]. However, the training regimen was moderate, the subjects remained asymptomatic and inter- and intrasubject variability was high. In another study, no significant change was found in groups of varying degrees of athletic activity [36]. Others have found transit time to decrease with treadmill walking or riding a bicycle ergometer [37]. The mechanism of these changes, if any, is speculative at this time.

Colonic symptoms may be treated in various ways. 'Nervous' or prerace diarrhea is generally self-limited and may respond to low-residue diets. Some have used prophylactic antidiarrheal medications. Ultraendurance athletes report that it is possible to 'train the gut' by reducing exercise duration and intensity to subsymptomatic levels and gradually increasing effort. Prerace cathartics should be avoided due to the possibility of dehydration. Race-associated diarrhea generally responds to reduction in effort. However, severe watery diarrhea associated with racing has not been well studied and will require intensive investigation in symptomatic runners. Exercise is said to benefit patients with functional constipation. Acute graded exercise reversibly reduces colonic pressure waves which may explain some lower GI symptoms associated with exercise [38]. However, recent studies found no obvious effect [39-41] of exercise on bowel transit or delayed transit with inactivity [42]. Medications such as NSAIDs may also be associated with colonic mucosal damage.

Was this article helpful?

0 0
Constipation Prescription

Constipation Prescription

Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.

Get My Free Ebook


Post a comment