What you need to know about exercise-induced nausea
You do it ! You train, you collect it all benefits of exercise that have been pierced through your head.
So you either pedal hard or run like escaping a horde of zombies. You feel fulfilled in seventh heaven until … your stomach starts to roll over. You may even feel dizzy. Your feelings of accomplishment have turned into agony as you face a bout of nausea.
So why is this happening and, more importantly, how can you prevent it?
The cause: competing demands
When you exercise, the skeletal muscles in your legs and arms contract. To work more efficiently, they need oxygen. So your heart muscle also contracts, increasing blood flow to your body. Hemoglobin molecules in your red blood cells carry oxygen to your working muscles.
To maximize the amount of blood delivered to active muscles, your body diverts blood from inactive areas, such as your gut. This diversion is overseen by the “fight or flight” branch of your nervous system. Known as the sympathetic nervous system, it causes certain blood vessels to narrow, which restricts blood flow. You do not have conscious control over this process, known as vasoconstriction.
But your contracting skeletal muscles have a special power to preserve blood flow. They are able to resist the call for vasoconstriction which helps to divert blood from inactive areas. This resistance to the effect of the sympathetic nervous system is called “functional sympatholysis. ” Physiologists like me continue working for understand the specific mechanisms whereby this can happen.
So why does restricting blood flow to the gut cause distress?
Relative ischemia, or lack of blood flow, can have different effects. It can change the way cells are able to absorb what has been digested and how broken down food moves through the intestine. Taken together, the changes lead to an uncomfortable feeling that you may not know all too well.
Lack of blood circulation is especially difficult if the digestive system is actively trying to break down and absorb food, a major reason for exercise-induced nausea. may be worse right after eating, especially if the pre-workout meal had lots of fat or concentrated carbohydrates.
The cure: Moderation and modification
It’s no fun exercising if you have stomach cramps or are running for the bathroom. So what can you do to limit the symptoms or eliminate them when they appear?
Moderate the intensity of your exercise. Nausea is more common with high intensity exercise, where the competing demands for blood flow are highest. Particularly if you are new to exercise, gradually increasing the intensity of the exercise should help minimize the likelihood of gastrointestinal distress.
Modify your exercise. There is some evidence to suggest that certain exercises, like the bike, can put the body in a position more likely to cause bowel problems. Try different forms of exercise or combinations of different modes to achieve your fitness goals while minimizing discomfort. Be sure to warm up and cool down to avoid rapid changes in your body’s metabolism.
Change what and when you eat and drink. Stay hydrated! You’ve probably heard it before, but drinking enough is one of the best ways to prevent gastrointestinal issues during and after exercise, especially in hot or humid environments. However, it is possible to overhydrate. To aim about half a liter per hour of liquids, including low-carbohydrate and sodium sports drinks for high-intensity exercise. You may need to experiment with different foods and when to eat them to determine what works best for you and your training goals. You can also incorporate foods like ginger, crackers and coconut water it might help calm your stomach.
The caveat: when to seek help
While exercise-induced nausea is uncomfortable to handle, it is usually not a major health problem. Most symptoms should go away within an hour of completing exercise. If the problems persist for long periods after exercise or each time you exercise, it is worth discussing with your doctor.
Sometimes gastrointestinal distress during or after exercise can lead to vomiting. If you unfortunately vomit, you’ll likely feel better, but you’ll also need to rehydrate and replenish the nutrition you’ve lost.
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If you’re looking to start an exercise program or increase the intensity of your current workouts, seeking advice from qualified professionals who can tailor a program to your needs is often a smart approach. Exercise physiologists Where certified personal trainers can provide an exercise schedule of appropriate intensity, and registered dietitians nutritionists can discuss individual nutritional needs and strategies. Your primary care provider can help screen for more serious medical problems and should also be informed about your exercise routine.
Anne R. Crecelius does not work, consult, own stock or receive funding from any company or organization that would benefit from this article, and has not disclosed any relevant affiliation beyond her academic position. .