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Runner’s guide to avoiding GI distress

It’s more common than we’d like to admit: getting the runs while on a run. Mary Luz Mejia explains how to time and choose the right nutrition so that you don’t have to make an unwanted pitstop.

washroom toilet

Most runners will tell you, there’s nothing worse than dealing with tummy troubles while out in the open during a run. Commonly referred to as the “runner’s trots,” this uncomfortable condition basically consists of “urgent, diarrhea-like stools, frequently accompanied by abdominal cramps,” explains Toronto-based registered dietitian Abby Langer. The longtime runner recalls that the first time it happened to her, she was on medication that aggravated her stomach. Subsequently, she found that the trots could be precipitated by running on really hot days, too.

Like Langer, other runners find that dehydration, diet, the gut being jostled during exercise, diversion of blood flow from the gut to the muscles and the secretion of gastric hormones that speed up transit time can all lead to a ruined run. Registered dietician and fitness specialist Jodi Robinson adds that eating too soon before a run and not eating the right types of foods also triggers gastro issues in newbie and seasoned runners alike. Many runners overeat leading up to a run out of fear that they will feel depleted during their workout. “The problem is, if your stomach is full and your body is busy digesting food,” Robinson explains, “it can lead to a sense of heaviness and fullness which is very distracting and uncomfortable during a run.” And, if timed incorrectly, the tummy will rebel during thousands of shakes it expe- riences as you put one foot in front of the other.

portapotty washroom

We asked Langer and Robinson for their top tips in avoiding the GI distress while training:

  1. Langer advises all runners keep well-hydrated. This means drinking before and during your run, especially if you’re going a long distance. Robinson adds, “beverages that are too concentrated in sugar (like pure fruit juice) are not easily tolerated because blood flow to the small intestine is reduced during exer- cise (going to working muscles instead), so the body can’t absorb the carbohy- drate efficiently leading to abdominal discomfort.” Her beverage of choice: water. “A sports drink is only necessary,” cautions Robinson, “if you’re running over 60 minutes and if your goal is performance-based, as sports drinks are formulated with the ideal carbohydrate concentration.”
  2. Avoid eating two-three hours before running, if possible, says Langer. Robinson advises that the closer to your run time, the lighter the meal and emphasis should be on carbohydrate- rich foods. She suggests runners avoid foods rich in fat, fibre and protein because they take longer to digest. A peanut butter sandwich on 100 per cent whole grain bread an hour before a run is not a good idea.
  3. The day of and night before a hard run or race, eat a bland, low-fibre meal. “High fibre meals and snacks can precipitate the trots,” says Langer.
  4. Avoid caffeine before a run unless you’re certain that you can tolerate it.
  5. Never try a new food before a race.
  6. “After an extended period of intense activity, the body is similar to a car that is out of gas,” says Robinson, adding, “Just as your car would need to be refuelled, you want to refuel within 30-60 minutes to promote exercise recovery. Choose a carbohydrate-rich snack or meal with some protein.” She suggests combinations like chocolate milk and a banana, a smoothie made with low-fat milk and fruit, a sandwich made with low-fat cheese or lean meat and fruit or milk.
  7. “When using gels, blocks and other energy foods,” says Langer, “be sure to try a variety during shorter, easier runs to see which ones you tolerate the best – then try them on a longer or harder run.”