Regular physical activity promotes the circulation of blood through your heart and blood vessels, which can improve your cardiovascular health and boost your energy levels. Feeling faint or weak during exercise could be your body’s way of saying it’s being pushed too hard, according to the Mayo Clinic. Faintness may also occur if your body isn’t properly nourished or hydrated. A few simple steps may keep you from feeling faint during a workout.
Eating and exercising go together. Your strength and stamina depend on the nourishment your body receives before physical activity. Exercising on an empty stomach may leave you feeling faint. Dehydration can lead to a drop in blood pressure, which can leave you feeling faint and fatigued, the Mayo Clinic says. Exercising in hot, humid conditions can lead to dehydration and severe overheating and dehydration. Faintness is one symptom of an overheated body.
Your body converts carbohydrates into sugar during digestion. When sugar enters the bloodstream, it makes its way into individual cells to provide energy. Excess sugar is kept in reserve in your liver and muscles as glycogen to be used during exercise. Vigorous workouts that last longer 90 minutes can drain your muscles of glycogen and make you feel weak and fatigued.
Eating carbohydrates one to two hours before exercising can give you the energy needed to sustain a workout and avoid feeling faint. Healthful choices include oat bagels, whole-wheat bread, bananas, raisins and peanut butter. Drinking a few cups of water before exercise and during physical activity can also prevent lightheadedness. Exercise in an indoor workout center or in the morning or evening hours during hot, humid weather to avoid becoming overheated.
Contact your health-care provider if you experience discomfort or pressure in your chest or upper-body area during a workout. The American Heart Association says chest pain that persists longer than 10 minutes could mean you're placing too much strain on your heart, which could result in a heart attack. Symptoms of a heart attack may include faintness, breaking out in a cold sweat and nausea.