Why You Get Nauseous or Dizzy While Exercising

Female jogger with water bottle
Tetra Images/Getty Images

There are certain unpleasant side effects of exercise that everyone expects, with sweating and muscles aches topping the list. But getting nauseated or dizzy during a workout? That can be both surprising and alarming.

Generally, these problems are usually associated with high-intensity exercise or endurance exercise, such as running too far or too fast. But even people who engage in more moderate exercises may find that a workout is making them feel sick.

Sometimes this may signal an issue that needs medical attention, so it's important to discuss any recurring problems with your doctor. Dizziness is often also a side effect of certain medications, including ones used to treat hypertension and depression. But there are other easily addressed causes of nausea and dizziness.

Plan Meals to Prevent Low Blood Sugar

If you usually work out in the morning before breakfast, that may mean your body hasn't had any fuel since dinner the night before. The likely scenario: You get up, start exercising, and your blood sugar plummets, leaving you feeling nauseous, lightheaded, and weak.

Instead of working out on an empty stomach, eat a light breakfast, preferably one that contains protein, complex carbohydrate, and some healthy fat (think peanut butter on a banana or avocado on whole-wheat toast). These types of foods will keep you going for a while. This advice also applies if you exercise right after work and before dinner. Food is fuel, and if you don't have enough in your system, you won't have the energy to keep up with the demands of your workout. Good on-the-go options include sports bars and trail mix.

Stay Hydrated to Dodge Dizziness

The importance of staying hydrated when you exercise can’t be stressed enough. Moderate types of exercise rarely require all the glucose and sodium that are often found in sports drinks, but a healthy dose of water is essential. Dizziness and nausea are both symptoms of dehydration. At the opposite extreme, if you drink too much water right before exercise, it may slosh around in your stomach and lead to nausea.

It's best to hydrate fully an hour before exercise, then every 20 minutes during exercise.

Slow Down to Head Off a Head Rush

Orthostatic hypotension (aka postural hypotension) is the technical name for that dizzy feeling you get when you stand up too quickly from sitting or lying down. It means there's been a sudden drop in blood pressure.

If you experience dizziness often when exercising, you should consult a health care provider. But if a head rush is an occasional occurrence, the best fix is to take your time when changing positions. If there's a particular exercise that you know gives you that feeling, try moving through it more slowly or just leave it out of your routine.

Orthostatic Hypotension

Steady Your Gaze to Avoid Motion Sickness

Another cause of a motion sickness-like experience during exercise is letting your gaze drift as you're moving. In most exercises, the head is held in line with the spine and the gaze is level from there. If your eyes are wandering or off center while you're moving, it can produce a disoriented feeling. So whether you're on a Pilates reformer, a rowing machine, or even doing crunches, pick one spot to look at rather than letting the eyes be unfocused.

Breathe Right to Prevent Lightheadedness

Many exercises, including swimming, weightlifting, yoga, and Pilates, coordinate breath with movement. Done properly, this can have a calming and integrative effect, as well as help you avoid feeling unwell from a lack of oxygen.

How you should breathe while exercising depends on what you're doing. For instance, when lifting weights, you should breathe out as you lift the weight and breathe in as you lower it. If you're prone to shallow breathing when walking and running, learning to breathe deeply from your belly will help you get a full inhalation and exhalation.

Diaphragmatic Deep Breathing Exercise

Avoid Holding Your Breath

People often hold their breath while working out, especially during high-intensity exercise. This can produce a sharp rise in blood pressure, followed by a sudden drop in blood pressure. Known as the Valsalva effect, it can lead to feeling dizzy and lightheaded and even cause you to faint.

Avoid Shallow Breathing

Many people keep their abdominal muscles sucked in continuously, thereby depriving themselves of the belly-expanding major portion of each breath. As a result, breathing becomes very shallow. This can be detrimental in situations, such as when you're walking or running at a moderate or fast pace and need more oxygen, as well as a recipe for feeling lightheaded.

Don't Overwork Your Breath

On the opposite end of the respiration spectrum, it is possible to overwork the breath. Because the breath is somewhat controlled in exercises like yoga, Pilates, and tai chi, it may be that you're breathing too hard for the amount of exertion you're actually putting out. Teachers may encourage students to exaggerate the breath so much that it could make you dizzy and create the beginnings of hyperventilation. If you're getting overworked with your breath, back off and find a flow that works for you.

Was this page helpful?
Article Sources
  • An Overview of the Problem: Exercise Training and Orthostatic Intolerance, Med Sci Sports Exerc. 1993 Jun;25(6):702-4. Review.
  • Paluska SA. "Current Concepts: Recognition and Management of Common Activity-Related Gastrointestinal Disorders". Phys Sportsmed. 2009 Apr;37(1):54-63. doi: 10.3810/psm.2009.04.1683."
  • Waterman JJ, Kapur R. "Upper Gastrointestinal Issues in Athletes." Curr Sports Med Rep. 2012 Mar-Apr;11(2):99-104. doi: 10.1249/JSR.0b013e318249c311.