Bowel function in runners after ingestion of sweeteners
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Published on: February 6, 2014
1Department of Internal Medicine and Public Health, Medical School, University of L'Aquila, L'Aquila, Italy.
Objectives:
This study investigates the bowel function in outdoor runners drinking sweetened solutions both by determination of H2 in exhaled air and asking about intestinal discomfort.
Materials And Methods:
Twenty-two athletes with a mean age of 22 +/- 3 yrs, received 100 ml of a 10% water solution of saccharose, glucose, mannitol, and isomalt respectively, before a 60 min outdoor run training. The trial was repeated on a rest day, one week later. Samples of the exhaled air were obtained at time zero (basal) and then every 15 min for a period of 3 hrs after administration of the solutions. The H2 was detected by breath test.
Results:
H2 excretion was lower during exercise. Suprabasal increments of breath hydrogen after saccharose load were significantly higher than after ingestion of mannitol (p < 0.05 between 1 and 3 hrs) and isomalt intake (p < 0.05 over 30 min). After glucose load, suprabasal increments of breath hydrogen were higher than after mannitol (p < 0.05 between 1 and 3 hrs) and isomalt (p < 0.001 between 1 and 3 hrs) ingestion.
Conclusions:
The intestinal discomfort in runners drinking sweetened solutions seems to be related to different bowel transit time.
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