Stomach Pain After Running? Here Are 6 Possible Causes + Fixes
Of the more glamorous things you can do in a day, exercise probably isn’t one of them. Spend enough time running, biking, or hiking in the great outdoors and you learn to get comfortable with bodily functions not discussed in polite conversation.
But no matter how seasoned you may be, coming to terms with a queasy stomach (often, an upset stomach after workouts) isn’t easy. Those who’ve dashed for the Porta-Potty or thought they were going to vom during CrossFit know just the feeling.
If it’s any consolation, you’re not alone. A recent study found that up to 70 per cent of athletes deal with GI problems. Other experts put the number even higher. About 95 per cent of my clients experience some GI problem throughout their careers. The most frequent symptoms read like a Pepto-Bismol jingle: nausea, heartburn, indigestion, and diarrhoea.
Exercise, especially running, tends to bring out symptoms. And though gastrointestinal distress isn’t usually a health threat, embarrassing symptoms can prevent sufferers from getting help and discourage them from exercising altogether.
So, if you find yourself wondering, “why does my stomach hurt after working out,” here’s what you need to know: When you begin your workout, the muscles you’re relying on most (e.g. your quads during a run) compete with your internal organs for blood. Your organs need blood for digestion; your muscles need it for strength as you exercise. Because the energy demands of your quads are greater, your organs lose out and your body directs a majority of its blood flow to your legs. In turn, the gastrointestinal system is left with fewer resources with which to digest the food and water you’ve taken in before or during your workout.
This is why, even just 20 minutes in, you may start feeling nauseous during your workout. Some people can exercise comfortably after wolfing down a meal 15 minutes before a workout. Others can’t eat anything within two hours or they’ll feel bloated and sluggish.
6 Possible Causes and Solutions for Stomach Aches During and After Running
Take a look at some of the things that are commonly thought to increase your chance of nausea and ways you can avoid this awful feeling (and repeatedly yourself asking, “why does my stomach hurt after working out?”) in the future.
1. Medication
Although it’s always important to take the recommended dosage of any medication, pay close attention to your intake of anti-inflammatory medicines; excessive amounts of ibuprofen or naproxen can cause nausea. So while it may be tempting to muffle your knee pain with OTC anti-inflammatories to get you through that tough workout, one too many can leave you feeling sick.
Never take more than recommended on the box or than prescribed by your doctor. And if taking an anti-inflammatory, do so post-workout instead. (And eat one of these 15 anti-inflammatory foods for a natural pain-tamer.)
2. Intensity Level
Surprisingly, exercise-induced nausea can happen at any speed and at any intensity. High-intensity exercise can increase your chance of nausea during workouts due to the sheer fact that the harder you work, the more you ask of your body; however, nausea can occur at any intensity level.
This is thought to be partly due to conditioning level. But emotions and anxiety play a large role too. If you’re stressed or excited about a competition. If you’re trying a new gym or new exercise routine, the nervous excitement could cause you to be nauseous during or have an upset stomach after workouts.
At the gym? Reduce your speed or resistance until the feeling subsides — usually fairly quickly after you slow down or stop moving. Simply take a step back, slow down, and rejoin the group once you feel better. Stop internally competing with yourself; if you get sick, no one wins.
3. Fitness Level
Although it’s reasonable to assume exercise-induced nausea can occur if a beginner pushes themselves too hard, or too fast, overall the phenomenon is not prejudiced to any skill level.
In fact, GI distress is relatively common among endurance athletes such as marathon runners or long-distance cyclists — some of the most “in shape” athletes in the world.
One study showed subjects of different genders and conditioning levels, asking them to fast, eat right before, or eat directly after exercise and found that food intake and intensity level affected nausea during workouts, but gender and conditioning level did not. Training did not decrease exercise-induced nausea.
Progress through your fitness level in stages. Don’t try an expert-level kickboxing class if you’ve never tried the technique before. There’s no shame in starting from the bottom—only up from there.
4. Dehydration
During exercise, blood flows away from your gut, towards larger working muscles. The problem is, inadequate hydration affects the volume of blood pumping through your body, which can exacerbate that GI distress and gut immobility — aka that stomach ache after a workout — mentioned above. Drink more water, more often. And not just when you’re exercising. Be aware of your hydration throughout the week.
5. Eating
Perhaps one of the largest players in the workout-nausea game is your diet. Eating a large meal and going to boot camp shortly after is a fairly obvious recipe for a stomach ache after workouts. Skipping meals or not eating a satisfying balance of protein and carbs can also play a role.
Too full and your stomach won’t have enough time to properly digest. Hungry? An empty gurgling stomach will have your water sloshing around in your stomach making waves. It may take some time to learn what’s best for your stomach, as it’s different for everyone.
Examine your pre-, during-, and post-workout eating habits. If you typically don’t eat for a long time before a workout, try having a small snack 30 minutes to an hour before. Conversely, if you tend to eat a lot before exercise, try to reduce the amount of food and replace it with a smaller amount of healthy fats, carbs, and protein such as nuts or nut butter on a piece of toast, she says.
6. Hormones
You’re familiar with the positive hormonal changes that occur with exercise. There are many different theories on how hormones may affect GI symptoms such as nausea during exercise.
One thought is that hormones are released from the brain and lead to a release of catecholamines (hormones released by the adrenal glands), which can then cause a delay in gastric emptying.
Take a pause if you’re feeling nauseous during your workout, and then join the game when you’re feeling better. You can still embrace these mental health benefits of exercise.
Why Are Stomach Problems Common In Runners?
Stomach problems are a fairly common malady for runners because running can be highly disruptive to the gut and digestive system. The jostling motion of running, and the impact forces for each step, jiggle and stimulate the gut, often triggering contractions of the smooth muscle lining the GI tract. This can contribute to diarrhoea from running, often termed runner’s trots.
Moreover, when you run or engage in other forms of vigorous exercise, blood is diverted away from the digestive tract to meet the increased demand from the heart, lungs, and working muscles.
This causes digestion to slow or nearly cease, leaving any residual food to hang around in your stomach. Therefore, if you go running after eating, undigested food in your stomach might slosh around, and the processing of it may come to a halt.
Plus, as food sits in the stomach and digestive tract, the bacteria in your gut ferment the sugars and produce gas, contributing to gas buildup and abdominal distention. Accordingly, you can experience gas, bloating, indigestion, abdominal cramps, side stitches while running, and stomach pain after running.
Ways To Prevent Stomach Problems When You Run
Given the litany of possible causes of an upset stomach while running or stomach pain after running, it can be difficult to pinpoint the exact issue and fix the problem. However, here are some useful solutions to stomach problems while running:
Examine Your Fueling Strategy
Ensure you’re waiting long enough to go running after eating. You should wait about 3-4 hours to run after eating a large meal, 2-3 hours for a small meal, and 1-2 hours after most snacks unless it’s a very small snack consisting of only simple carbohydrates. Limit fatty foods, fibrous foods, artificial sweeteners, carbonated beverages, and excessive caffeine before you run.
Rethink Hydration
If you are well-hydrated, your urine should be pale yellow. If you are feeling bloated, consider sports drinks with electrolytes. The general recommendation is to drink 4-6 ounces of fluid every 15 to 20 minutes during your run, depending on the environmental conditions, your sweat rate, the intensity and duration of the run, and your pre-run hydration status.
Slow Your Pace
Slowing down will reroute more blood to your stomach and digestive tract. It also eases respiration and can prevent stitches.
Fix Your Running Form
Hunching over can compress your diaphragm and lungs and can cause side stitches while running. Make sure you are running tall.
Strengthen Your Core
A strong core can support good running form and prevent side stitches.
Breathe Evenly
Slow, even breathing while running can prevent side stitches and ensure you don’t swallow too much air, which can lead to bloating, belching, and flatulence.
Avoid the Hottest Part Of the Day
During hot, humid weather, try to run in the cooler morning hours or evening hours, or consider taking your workout to a treadmill indoors.
Try Ginger Chews
Ginger can ease nausea and indigestion. Try some ginger chews.
See a Gastroenterologist
If you have concerns about a gastrointestinal disorder that might be interfering with your running and overall health, speak with your doctor about seeing a specialist.
How to Deal with Stomach Problems for Runners
The key is to know which side effects are apt to accompany your favourite fitness activity and practice these smart strategies to minimize them.
- Abdominal cramping
- Diarrhoea
- Side stitches
All that pavement-pounding jostles the gastrointestinal tract and its contents, triggering lower GI problems. Numerous studies have found that about 50 per cent of long-distance runners report problems such as cramping and diarrhoea during the event.
Side stitches (which vary anywhere from a dull cramp to a sharp stabbing pain in the side of your abdomen) are caused partly by gravity and the natural movement of running, which strains connective tissues in the abdomen.
To redirect blood to your gut, slow your pace until your heart rate decreases to a comfortable level. For side stitches, change your stride, slow down, or twist your torso gently in the direction opposite your side ache. A true emergency? Find the nearest Porta-Potty or big tree. You won’t be the first or the last to do so trust me.
- Hydrate. Drink 4-6 ounces of fluid every 15 to 20 minutes during your workout, alternating between water and sports drinks for longer sessions to replenish electrolytes.
- Ditch the soda. Cola is sometimes used as a pre-race drink thanks to the stimulating effects of its caffeine and sugar. But carbonated air bubbles cause bloating.
- Dodge the fat. Nix fatty meals a full day before a big workout because fat and fibre are digested more slowly than carbs or protein. Also, foods containing lactose (dairy), sorbitol (sugarless gum), and caffeine activate the GI tract. Avoid them starting four hours before your run.
Still, Have a Stomach Ache After Workouts? Try These Natural Stomach Soothers
These herbs might help take the edge off workout-induced tummy upset. You can find them in capsule form at your health food store, but the simplest way to get your daily dose is to drink them in tea.
- For gas and heartburn: Try chamomile. This pre-bedtime beverage may be a powerful anti-inflammatory. A cup of chamomile tea is used to soothe and calm the entire digestive tract.
- For nausea: Try ginger. Ginger is believed to settle the stomach by suppressing gastric contractions and aiding digestion.
- For cramps and diarrhoea: Try peppermint. Peppermint has menthol, which may help control muscle spasms that lead to cramps and the urgent need to go to the bathroom.
