According to the American College of Sports Medicine, regular exercise can help control body weight and lower your risk of disease. To prevent chronic disease, ACSM recommends a minimum of 30 minutes of moderate exercise each day. However many people increase the amount and intensity of exercise in an effort to lose or manage body weight. Occasionally, you may feel nauseated or light-headed after a workout, and this may be preventable.
There are many different reasons that you may feel nauseous or light-headed after your workout. If you exercise too much or at too high of an intensity, you put stress on your body and do not allow it to recover. It is possible that you did not prepare yourself properly for exercise by warming up and cooling down, which affects heart rate and blood pressure. Dehydration can be a problem if you sweat a lot and don't drink enough during exercise. If you did not eat or ate too close to exercise, nausea and dizziness can occur.
You may experience signs before or during exercise that indicate you should ease back or not exercise that day. These include feeling fatigued and getting inadequate sleep, or experiencing body aches for no apparent reason. Also, feelings of hunger or thirst can cause problems during and after your workout. Your heart rate and/or blood pressure may be higher than normal, and you find that you cannot converse during exercise. Any one of these things can lead to feeling nauseated and light-headed after your workout.
The National Strength and Conditioning Association recommends starting your session with a warm-up. This allows your body to prepare for exercise and increases body temperature. Slowly increase the intensity until you feel that your exercise is moderate to hard but not unbearable. To avoid over-training, gradually increase the duration of your exercise as well. End your session with a cool-down so you can bring your heart rate, blood pressure and body temperature back to normal.
Fuel and Fluids
Eat a small meal of about 200 to 300 calories one to two hours before exercise, recommends Registered Dietitian Nancy Clark. You may need to try out different foods to see what works well for your body, but it is important to fuel your exercise to avoid feeling ill during or upon completion. Water is usually adequate to avoid dehydration if you drink before and during exercise. If you exercise for more than an hour, you may want to have a sports drink to replace carbohydrate and electrolytes lost from exercise and sweating. Whatever your fluid choice, drink it in sips rather than gulps.
If you have been ill, don't expect to jump right back into exercise. Listen to your body, and slowly bring your exercise session to the level it was before the illness. If you have a chronic condition and/or currently take medications, discuss exercise with your doctor. Find out whether you should avoid certain exercises and the side-effects of your medications to avoid nausea and a light-headed feeling.