Reasons why you get nauseous during or after working out:
1. Eating and drinking before a workout.
2. Nausea also happens during exercise because blood flowing to our GI tract and stomach is rerouted to the muscles we’re working, thus slowing digestion and causing discomfort.
3. If you ate even within two hours of working out, the reduction in flow to the GI tract may add to the feeling of nausea or dizziness caused by dehydration, often leading not just to nausea, but actually getting sick.
4. Avoiding eating right before working out is something most people know to do. But foods that are high in fat and protein can take twice as long to digest than more easily digested foods, like toast or bananas. That makes them more likely to cause nausea.
5. You don’t want to eat too much before a workout regardless of the food, but easier-to-digest foods will be better before a workout. And try to eat about three hours before you begin.
6. While you want to be hydrated, you also don’t want to overhydrate. Too much water actually dilutes your electrolyte levels, causing hyponatremia, low sodium concentration in the blood. And you guessed it: This can lead to nausea.
***How you can feel better during or after working out?
Don’t drink abnormally large amounts of water before you work out, and choose foods that digest faster a few hours before you start exercising.”