Feeling Queasy After Your Workout? Find Out What Causes Exercise-Induced Nausea

Feeling a bit queasy after your workout? Nausea during exercise is a common complaint. It even has an official name – exercise-induced nausea. It can occur with high-intensity exercise or low- intensity exercise and with strength-training or cardio. People who have it will agree it’s a frustrating problem, especially if it happens frequently. What causes nausea with exercise, and what can you do about it?

Dehydration May Be a Factor

Are you drinking enough water during your workouts? Dehydration slows down stomach emptying, and delayed gastric emptying can trigger nausea and other digestive symptoms. The take-home message is to stay hydrated while working out, but don’t go overboard. Drinking too much water can cause queasiness by overfilling your stomach and diluting electrolytes. Drink between 8 and 10 ounces before a workout and another 8 ounces every 15 minutes during exercise. When you drink, don’t gulp or fill your water bottle with carbonated beverages. Gulping fluids and drinking carbonated beverages contributes to air swallowing, which can cause nausea. Don’t hydrate with caffeinated beverages. Caffeine stimulates the production of stomach acid and can lead to an “acid stomach’ and nausea.

How Eating or Not Eating Affects Exercise-Induced Nausea

Eating a big meal before exercising can cause nausea, especially if you’re doing high-intensity exercise or running long distances. That’s why experts recommend waiting at least two hours after eating before heading to the gym. In a study published in the journal Appetite, researchers found that volunteers who ate immediately before exercise were more likely to feel nauseated, especially during and after high-intensity exercise. This isn’t surprising since exercise diverts more blood flow to hard-working muscles and away from the digestive tract.

At the opposite end of the spectrum, low blood sugar levels from not eating can trigger nausea. Low blood sugar levels also cause fatigue and lightheadedness and make it more difficult to work out. This is common in people who wake up in the morning and do cardio on an empty stomach.

If you routinely jump on the treadmill before breakfast, eat a combination protein-carb snack beforehand to sustain your blood sugar while you’re exercising. A 200-calorie snack consisting of a fruit smoothie, peanut butter on whole-grain crackers or a protein bar should be sufficient. When you finish your workout, cool down for 10 minutes and rest for another 10 minutes to allow blood flow to be redirected back to your intestines. Then eat your post-workout meal.

If you’ll be exercising for more than an hour, drink an electrolyte-rich sports drink that contains carbs to stay hydrated, replace electrolytes and keep your blood sugar level stable.

Other Tips for Avoiding Nausea after Exercise

If you’re working out in a hot environment, wear loose cotton clothing. Becoming overheated can trigger nausea, especially if you’re not drinking enough. Nausea during or after exercise can also be a sign of a condition called GERD or gastroesophageal reflux. With GERD, the band of muscle that separates the stomach and esophagus is weakened, allowing stomach contents to move back into the esophagus and throat. This can lead to chest discomfort, nausea and an acid taste in the mouth. Weight training can aggravate this problem, especially if you lift immediately after eating and bend over often to pick up or adjust weights. If this is a frequent problem, talk to your doctor about medications that can help.

Nausea during or after exercise can also be a sign of iron-deficiency anemia, a condition that’s common in young female athletes. If the problem persists and you’re feeling weak and tired, see your doctor.

References:

Eur J Appl Physiol. 2000 Dec;83(6):578-84.
Appetite. 2001 Apr; 36(2): 119-25.

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