Have you ever felt nauseous during a tough workout? Have you ever had that butterflies in your stomach feeling from nerves or stage-fright? Like most people you probably have, and it’s because the two phenomena are closely related. While some people see nausea as a badge of honor and proof of a great workout, it isn’t necessary to push yourself until you’re doubled over in misery in order to get results. Once you understand why it happens, you can make some simple adjustments to keep it from happening in the future.
1. Too much food or liquid in your stomach before a workout: During times of great stress or danger, your body releases adrenaline in order to quickly mobilize fuel for your muscles and direct blood flow to your legs and arms so that you can either fight off danger or run away. Since you only have so much blood, a side effect of this increased blood flow to your limbs means decreased blood flow to your digestive system. Once the blood leaves this area, anything left in your stomach (even water) is going to sit there like a rock and cause discomfort.
Exercise causes a similar reaction by releasing noradrenaline (adrenaline’s little brother) to help power the energy demands of your exercising muscles. Once again, anything left in your stomach is going to sit there undigested, but it will feel even worse because all that movement will cause it to slosh around in your stomach and esophagus.
Make sure you give your body time to move food out of your stomach and into your intestines for absorption (known as gastric emptying) before you exercise. It typically takes 1 to 2 hours to clear out your stomach, but foods high in fiber, fat, or protein can delay gastric emptying and increase your chances of nausea during your workout.
2. Dehydration: While it’s true that drinking too much before or during your workout can leave all that liquid sloshing around in your belly during exercise, dehydration has been shown to significantly delay gastric emptying as well. This means that if you don’t adequately hydrate yourself before your workout, you can cause your pre-workout meals to linger.
3. Low blood sugar: Despite what Gatorade and Coca Cola want you to believe, you don’t actually need to load up on sugar before your workout to make it through. Our bodies are incredibly adaptable and we were meant to thrive in an environment where food is scarce. While we don’t need additional calories to successfully complete a workout, long workouts (over an hour) and extremely intense workouts can temporarily deplete blood sugar levels and cause feelings of nausea due to mild hypoglycemia. Unless you’re diabetic and taking medication to manage your insulin, this is rarely harmful, but it can still be unpleasant. A quick infusion of carbohydrates can help with nausea, or you can simply ease up a second and let your body mobilize it’s glycogen reserves. While the amount of glycogen people can store will vary, a typical marathoner will have enough glycogen to fuel them for 2 hours before they “hit the wall.” Since the average person isn’t pushing to this extreme a level, simply easing back a little when you feel nausea coming on will give your body time to stabilize your blood sugar levels from your internal reserves.
While the type of training you’re doing, your overall diet, and your own unique physiology will determine how much gastric emptying, dehydration, or low blood sugar will impact you, there are still some simple adjustments everyone can make to keep nausea at bay. If you’re prone to exercise-induced nausea, it’s worth consulting with a physician to see if there is an underlying medical issue, but to make sure you don’t need to reach for a trash can during your next workout, experiment with these simple tips:
1. Give yourself time to digest: Don’t eat a large meal within 2 hours of your workout. You should add another hour to that timeframe if the meal was high in fiber, solid protein, or fat since these foods typically delay gastric emptying. While this is great for keeping you feeling full and satisfied longer, it’s also a good way to turn your workout into a miserable experience. Even smaller snacks should be consumed at least 30 minutes before your workout.
2. Hydrate but don’t overdo it: As I mentioned in a previous article, companies like Gatorade convinced us that we can’t trust our thirst and that we should force hydration. Not only is this unnecessary, but it can lead to nausea or even a dangerous condition known as hyponatraemia. Have a little water about 30 minutes before your workout and then sip throughout if you feel thirsty. If you force yourself to guzzle water, you’re just going to stretch out your stomach and increase your discomfort.
3. Warm up: I’m a big fan of high intensity training, but you shouldn’t just jump right into your tough workout without warming up a little first. Start with some light cardio or try out the dynamic warm ups found in Performance Stretching. It not only gets the working muscles, tendons, and ligaments ready for your workout, but light activity will actually accelerate gastric emptying of fluids which will decrease your likelihood of nausea later on.
4. Work up to it: New exercisers tend to do too much too soon when they start a new exercise routine. Not only can this lead to injuries, but it also increases your likelihood of pushing yourself into a hypoglycemic state before your body has adapted it’s energy systems. Start off with shorter, less intense workouts for the first few weeks and increase the length and intensity of the workouts as your fitness improves. We are amazingly adaptable, but you still need to give your body time to adjust.
5. Don’t push through: Just like you shouldn’t do too much too soon, you should also ease up when you’re body is telling you you’re pushing too hard. It’s unlikely that you completely depleted your glycogen reserves and often times just easing up a little when you feel nausea coming on will give your body time to stabilize your blood sugar. Don’t let pride get in the way of common sense. I enjoy pushing myself through a high intensity workout, but if my knee or shoulder joint was screaming in pain, I would listen to my body’s feedback and ease off before I cause an injury. Nausea is simply another type of feedback. If you listen to your body’s signals and adjust as needed, you’ll ultimately get more out of your workouts than if you push too hard and need to cut your workout short so you can lie down.
6. Don’t sit down to cool down: As I mentioned in a previous article, carbon dioxide-rich blood tends to pool in your leg muscles after a tough workout, and sitting down will require extra work from your heart to get that blood back to your lungs so those waste products can be removed. This extra effort can make you feel light headed and nauseous. However, if you walk around slowly afterwards, the movement of your leg muscles will pump the blood back towards your core and help you recover faster. Walking slowly will allow you to recover faster than sitting, but if you’re feeling absolutely wiped out, you can also lie down with your legs elevated to help drain the blood from your legs.
Listen to your body and adjust
Nausea can be a pretty unpleasant form of feedback from your body, but ultimately it’s just another signal that you need to monitor and adjust to. Maybe you need to change your pre-workout nutrition. Maybe your body isn’t ready for an increased level of intensity. Maybe you’re drinking too little or even too much. Don’t just write off nausea as a random and unlucky fluke. Pay attention to what came before and adjust your habits so it doesn’t happen again.