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Thursday, May 22, 2014

FRUIT AS FUEL

There I was, among 700 other athletes getting set to tackle the eight-mile ascent of Mt. Baldy, in the annual Run to the Top trail race last September. It was about five minutes before the start when it hit me, that all too familiar feeling. It began with the sound of a missile going off in my belly, which was followed by a stifled burp, and then the inexorable urge to find the nearest toilet. I scanned the surroundings and about 100 feet away I espied three porta potties - with about 30 panicked runners waiting to use them. Clearly I was not the only one experiencing, shall we say, intestinal urgency. I plastered a grin on my face, excused myself from my fellow competitors, and managed that tell-tale splint-legged, butt-clenching speed walk to the closest and largest tree, disappeared behind it, and…you can probably guess the rest. Thank goodness there were leaves.

Gastrointestinal symptoms are so common among runners that they even have their own cute little nickname: the trots. A blanket term used to describe a wide array of symptoms including diarrhea, gas, bloat, reflux, side aches, nausea, belching, and sloshy stomach contents, runner’s trots have nearly as many possible causes. Often they are blamed on pre-race jitters or the act of running itself, which shunts oxygen away from the gut and disrupts the digestive process. And of course foods are also implicated, with food sensitivities and high-fiber favorites like bran cereal and whole grains heading the list.

But in the discussions about how best to avoid the trots, amid the calculations of precise ratios of macronutrients and how much water, salt, and other electrolytes the pre-run meal should contain, what often gets ignored is the effect of food combination. In other words, a given meal can provide all the right ingredients - a little protein to speed muscle recovery, slow-digesting carbs for prolonged energy, maybe some vitamins and minerals - but if you cannot absorb it rapidly or if it causes GI distress, the nutritional benefits are largely cancelled out. Worse, improperly combined foods could lead to an embarrassing pit stop before or during a race, or the ever-dreadful DNF.

So what do you eat before a run? Oatmeal and raisins? Bagel with peanut butter? Maybe a couple gels washed down with a sports drink? If the answer is yes, and if you are plagued by trotitis, your pre-race meal could use a make-over, as did mine.

First, for most foods, if it’s in a package, be wary. Manufacturers have evolved subtle and sly methods for sneaking not-so-healthy ingredients into their products. Consider that maltodextrin, a common sweetener found in sports gels, if not derived from wheat (a no-no for those with gluten sensitivities) is usually derived from genetically-modified corn. According to the Institute of Responsible Technology, GMOs pose many potential health risks. Rats fed these Frankenfoods develop stomach bleeding and immunological dysfunction in addition to a whole host of other problems. It is preferable whenever possible to avoid labels altogether and enjoy real food, and many coaches and elites are beginning to stress the importance of whole foods over gels, bars, and other packaged products.

But even if you make minimally-processed foods your staple, it is important to pay attention to how those foods are combined. Your body handles protein, carbs, and fats differently. For example, protein requires an acidic medium, while carbohydrates and fats require an alkaline environment. Pairing foods high in protein with foods high in carbohydrates can stall the digestive process and give rise to that sloshy feeling which can make running so unpleasant. This means avoiding common combos such as granola with yogurt, or cereal and milk. High fat foods, like nut butters, slow the digestive process and remain unabsorbed in the gut, the concentrated energy they contain being of no immediate use to the exercising athlete. And your body cannot absorb the complex carbohydrates in bread or cereal without first breaking them down to simple sugars, which takes time, and could add precious minutes to your finish time. Moreover, grains, whether whole or refined, are very dry foods, which can lead to dehydration if not consumed with enough water.

So what then should you eat? Because exercise burns a lot of sugar (in the form of glucose), your first priority should be to stock and replenish glucose as quickly as possible, which means ingesting it in its simplest form. For this, fruit would seem to be ideal. Fruit is naturally packed with a perfect mixture of water and fiber – melons typically are 95 percent water by weight - and the simple carbohydrates fruit contains, in the form of fructose and glucose, are quickly absorbed into your bloodstream to provide immediate energy to exercising muscles. In fact, fruit sugar is more readily usable than even the sugar in sports drinks, which is usually sucrose, a two-molecule pair that requires enzymatic activity before it can be absorbed and used. While some may argue that the fiber in fruit is a main culprit in the setting of stomach upset and bloat, the opposite is actually true: fiber is the preferred energy source for colonocytes (the cells of your colon), meaning it aids digestion. And the fiber in fruit helps keep blood sugar levels steady, while slowing colonic emptying and preventing intestinal urgency and diarrhea. The stomach upset resulting from eating high fiber foods usually results from improper food combination. The human digestive system evolved eating one food at a time, whatever was to be found, be it a field of greens or a felled beast, and our digestive anatomy hasn’t changed from the time of our prehistoric ancestors, so it is best to keep it simple. If you want to avoid hidden ingredients and gastrointestinal distress, choose real food, and focus on fruit. Blend several oranges into a homemade juice with the pulp. Mix a cup of your favorite berries with a frozen banana or two and a little water. Or try my personal favorite: salted dates. Avoid paring fruit with other foods, since its absorption is impaired by the presence of too much protein or fat, and choose fresh or frozen varieties over dried fruits like raisins and prunes, which can be harder to digest. And since fruit is lower in calories relative to other foods, you may need to make your pre-run meal a bit bigger. Don’t worry: The added bulk is mainly in the form of water, which will keep you hydrated without weighing you down. Make fruit your friend.

2 comments:

  1. My prerace is oatmeal with lots of fruit or just fruit by itself. The iron stomach doesn't give me many problems with the trots, but in longer races I usually have to stop once. not too bad.

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