Daily Archives: September 9, 2013

The effect of probiotics on marathon runners

If you’ve been closely following my blog, you know I’m a big fan of probiotics. Or more like obsessed. Probiotics help establish and maintain healthy gut bacteria, which are good for digestion and may also help boost the immune system. My preferred source of probiotics is from fermented food like kimchi and kefir drinks, instead of supplements. I’ve long had a delicate digestive tract, and I believe probiotics have been a big help to me over the years. I believe the kefir I often drink probably helped prevent stomach pain when I was running around the Hudson Highlands just the other day. I sometimes get stomach pain during very strenuous exercise.

But what does the science say when it comes to probiotics as a means to prevent or treat digestive problems which often plague marathon runners? According to the University of Helsinki, Helsinki, Finland, in The effect of probiotics on respiratory infections and gastrointestinal symptoms during training in marathon runners:

Heavy exercise is associated with an increased risk of upper respiratory tract infections. Strenuous exercise also causes gastrointestinal (GI) symptoms. In previous studies probiotics have reduced respiratory tract infections and GI symptoms in general populations including children, adults, and the elderly. These questions have not been studied in athletes before. The purpose of this study was to investigate the effect of probiotics on the number of healthy days, respiratory infections, and GI-symptom episodes in marathon runners in the summer. Marathon runners (N = 141) were recruited for a randomized, double-blind intervention study during which they received Lactobacillus rhamnosus GG (LGG) or placebo for a 3-mo training period. At the end of the training period the subjects took part in a marathon race, after which they were followed up for 2 wk. The mean number of healthy days was 79.0 in the LGG group and 73.4 in the placebo group (P = 0.82). There were no differences in the number of respiratory infections or GI-symptom episodes. The duration of GI-symptom episodes in the LGG group was 2.9 vs. 4.3 d in the placebo group during the training period (P = 0.35) and 1.0 vs. 2.3 d, respectively, during the 2 wk after the marathon (P = 0.046). LGG had no effect on the incidence of respiratory infections or GI-symptom episodes in marathon runners, but it seemed to shorten the duration of GI-symptom episodes.

So the probiotics didn’t reduce the incidence of GI problems, but they seemed to shorten their duration. This is good enough for me!

See “New Speed Record Set Today” which is about the possibility of cherry kefir juice(all vegan) improving my running.