Have you ever finished a workout and found yourself feeling queasy? It’s not as unusual as you think. Feeling nauseous after a workout is common, and there are a couple of reasons it can happen. If you’re wondering why you feel sick after a workout, we have the answers.

Common Causes of Feeling Sick After Exercise

Unfortunately, nausea after exercise happens. Unless you’re working out while pregnant, nausea after working out is typically caused by:

• Dehydration
• Delayed emptying of the stomach
• Lack of sodium in the blood (called hyponatremia)
• Reduction in blood flow to the digestive tract

All of these causes can mess with your body and lead to nausea after working out. You’re most likely to feel nauseous after a workout when:

• Starting or ending abruptly: Warm-ups and cool-downs help your muscles, but they also help your heart rate adjust to your activity level. This prevents your organs from experiencing sudden changes in blood flow, which can leave you feeling queasy.
  

• Eating too close to your workout: With the increased blood flow to your muscles during exercise, the blood flow to the digestive tract is reduced, so things take longer to digest. You should eat before a workout, but not right before. Ideally, eat 3 hours before exercising, although two hours will work if you eat easily digested foods.
  

• Hydrating too much or not enough before exercise: Dehydration causes nausea, but so does overhydration, which messes with your electrolyte balance and causes low sodium in your blood. Drinking too much during exercise can make you feel sick. Take tiny sips of water during a workout to avoid this.
  

• It’s an intense workout: When you push your body to go harder than it wants to, it might respond with an upset stomach. Increase intensity gradually to avoid nausea and injury.
  

• Working out in the heat: Dehydration is typically the culprit behind this one since you lose so much more water when it’s hot. Your blood pressure can drop in the heat, too, and that can make you feel light-headed and, you guessed it, queasy. 

The Impact of Overtraining on Your Body

If you work out too hard and experience workout sickness, you might be overtraining, which can have serious impacts on your body, including dehydration, fatigue, increased soreness, and a weakened immune system. If you don’t give your body a chance to recover, these symptoms can progress to more serious symptoms like insomnia, high blood pressure, or unusual changes in your heart rate. If you notice you’re nauseated or vomiting after physical activity, listen to your body and rest so it can recover properly.

When to Seek Medical Advice

If you periodically feel nauseous after a workout, that’s probably not a big deal. Adjust your eating and drinking habits, ease up on your workouts, and warm up and cool down properly. However, if you do those things and you still experience nausea after exercise, see your doctor for a check-up. Additionally, if you experience more serious symptoms, including black or bloody stool, severe stomach pain, or vomiting blood, see a doctor right away, as they could be signs of more serious issues. 

Tips for Preventing Post-Workout Nausea

Still asking, “Why do I feel sick after I work out?” It’s time to take prevention seriously. Here’s what you can do to stop feeling queasy after working out.

Eat Properly Before Exercise

Dairy, fat, fiber, and protein are harder for your body to digest, so eat these slow-digesting foods at least three hours before working out. Two hours before working out, focus on high-quality carbohydrate foods like sweet potatoes or bananas. Nut butters are a great choice, too. 

Don’t Overdo It

You’ll feel nauseous after a workout if you push yourself too hard. Try shorter or lower-intensity workouts to see if your nausea abates before building slowly back up. Avoid exercising in high heat, and incorporate warm-ups and cool-downs so your body isn’t shocked by changes in activity. If you’re not feeling well, consider skipping exercise. Working out while sick can further tax your immune system.

Stay Properly Hydrated

Too much water can make you queasy after working out, just like being dehydrated, so find the right balance of hydration. Drink water throughout the day before and after a workout, but don’t chug a bunch right before exercising. Take small sips of water during your workout as necessary. Consider drinks with electrolytes if it was a tough workout or you were sweating a lot, but don’t drink them beforehand as they take longer to digest. Avoid caffeine too close to a workout. 

Staying Healthy and Energized After Your Workout

You can usually prevent workout sickness before it starts, including taking care of yourself after a workout. Rehydrate after exercise and eat a snack with protein and carbohydrates within 45 minutes of your workout to help your muscles recover. And get your rest! Your body needs to recuperate after a workout. Incorporate recovery days with light exercise and get enough sleep so your body can heal. Your body will feel stronger, and you’ll have more energy when you take good care of yourself.