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All but the luckiest of runners have experienced the discomfort of nausea during a long run. It can easily ruin a training run, or, worse, a race you’ve trained months for. It can bring you to your knees, literally. What can you do about it? A whole lot.
Nausea while running is a multiple-threat danger. The key to defeating it is identifying which cause or causes are the day’s possible threats. Aside from sprinting some heinous hill, the most likely causes of running nausea are dehydration, salt intake, what you’re eating, heat and unsustainable running intensity.
1. Salt and Water
“Hydration-and-electrolyte balance is number one,” says Meredith Terranova, sports nutritionist, ultrarunner and owner of Eating and Living Healthy, when asked what runners can do to prevent nausea. She continues, “A runner needs to balance the amount of water required for different conditions, then match that with a consistent intake of electrolytes, whether in drink or pill form.” Nausea resulting from dehydration and/or electrolyte imbalances occurs because both water and electrolytes are digestion requisites. Without the correct volumes of both, portions of the process break down and leftover stomach contents induce the desire to vomit.
2. Sweet But Not Too Sweet
The proper water-electrolyte balance is hard to find, as consuming a too-high ratio of carbohydrates and water may make you ill, by slowing down gastric emptying (more on that later). Always take gels with at least six ounces of water, be careful not to “overdose” on carbs when combining gels and sports drink and never over-concentrate sports drink.
To be more technical, Robert Kunz, VP of Science and Technology at First Endurance, explains, “In cold conditions athletes can typically consume a much stronger concentration of calories to fluid, nearing 20 percent. In hot conditions when the body needs more fluid and where it is spending a fair amount of energy cooling itself, try not to exceed a concentration of eight percent, which equates to 100 calories per 12 ounces of fluid.”
Even if you’re maintaining the right carb-water balance, be careful not to consume too many calories in too short of a span. Terranova advises, “Remember, the body can only process a limited number of calories in an hour. So, ‘getting ahead’ or overeating in a short period of time causes most of the food to sit in your stomach.” As we now understand, lingering stomach contents often result in a nauseous feeling.
3. Blood Feud
Our muscles are the big draw on our limited blood supply while running. However, during your long runs you’ll likely eat, as well as face an increased likelihood of prolonged heat exposure. As a result, you may be placing two or three extra demands on your blood supply.
Let’s look at the simple scenario of eating on the run. If you’re running at a relaxed effort, you’re not maxing out your body’s ability to supply oxygenated blood. Eat an energy gel, a Snickers or, say, a small slice of pizza and you (and your stomach) should feel fine.
Step up the pace, though, and the story changes. “The faster you run, the less blood flows to your gut,” explains Terranova. An increased effort draws additional blood flow to your hard-working muscles and away from your stomach. When that happens, your digestion slows and you’re left feeling less than rosy.
A hot day further complicates digestion. While the human body is well adapted to exercising in heat, dissipating heat through evaporational cooling provided by sweat on the skin, the process shunts blood to the skin.
It all adds up to three major draws on your blood flow: muscles, skin and stomach. Can you guess the loser? Yup, your stomach.
The simplest solution to any blood battle, advises Terranova, is simply backing off your effort for a while. Another short-term remedy is to eat just before a stretch in which you’ll be working less, such as a long downhill or an aid station you’ll be visiting for more than a couple minutes.
4. Rising to Your Feet
If nausea or a bout of vomiting has stopped you in your tracks, your run or race doesn’t need to end. Many ultrarunners employ a self-induced hurl to help reset the stomach. “I haven’t found specific scientific research on this,” says Terranova on the ol’ ultrarunning wives’ tale, “but I know many ultrarunners discuss its benefits and I’ve even seen it work.”
The longer-term (and more widely-recommended) solution is to slow down, cool off (if relevant) and take care of yourself. Once you’re able, start to eat and drink (in moderation) again while being extra careful of your electrolyte-water and sugar-water balances.
Tips on Not Tossing Your Cookies: Trail runners weigh in on how they deal with nausea
• When you start to feel nauseous, Texas-based, long-time ultrarunner Olga King says, “Drink ice-cold water and eat no food for at least 45 minutes.”
• “At the 2011 Western States 100, I vomited after taking too much salt,” says 2011 and 2012 Western States champ and course-record holder, Ellie Greenwood. “To recover, I backed off the salt, slowly sipped plain water and tentatively took gels for the next two hours until my stomach settled.”
• “Mints, ginger ale, S! Caps, Tums and/or apple juice,” is how Pennsylvania ultrarunner and Badwater Ultramarathon finisher Meredith Murphy treats her nausea. She has a last resort, too. “Sometimes I just puke and keep going.”
• Utah-based Emily Mitzel reflects on her recent finish at the 2012 Wasatch 100 (which included a couple bouts of puking), “My biggest advice about nausea is what I call ‘riding the fence.’ Push yourself hard enough to get on top of the fence but not so hard that you fall over it. During Wasatch, I kept leaning too far over the fence.”