What Triggers a Heart Rate Increase?

A normal heart rate ranges from 60 to 100 beats per minute (bpm), according to Dr. Edward Laskowski of the Mayo Clinic. Heart rates in the lower range correlate with healthier lifestyles, while elevated heart rates of 100 bpm or higher, defined as tachycardia, may indicate cardiovascular abnormalities. An increase in heart rate can arise from a wide range of circumstances, some normal and others not.

Exercise

• You can increase your heart rate by exercising.

  An increase due to exercise helps strengthen the heart. To obtain the full benefits of exercise, you should aim to raise your heart rate to about 60 to 90 percent of your maximum heart rate, which represents your "target" heart rate. You can calculate your maximum heart rate by subtracting your age from 220, as indicated by Medline Plus.

Pregnancy

• Increased heart rates are normal during pregnancy.

  During pregnancy, a woman's heart rate typically rises about 10 to 15 beats per minute. The Miller Family Heart and Vascular Institute at the Cleveland Clinic notes that this increase ensures that both mother and baby receive adequate oxygen. The increase, however, may cause a woman to feel more tired, lightheaded and short of breath.

Stress

• The Mayo Clinic reports that mental stress causes the heart to beat faster and blood pressure to rise. When you encounter a stressful situation, your body's adrenal glands, sitting atop each of your kidneys, start producing stress hormones such as adrenaline and cortisol. These hormones, in turn, act on your body to increase heart rate and blood pressure. After the stressful situation passes, your body's organs return to normal. When you experience constant stress, adrenaline and cortisol actually do damage to your body, ultimately contributing to heart disease and memory loss.

Cigarette Smoking

• Smoking cigarettes raises heart rates in a detrimental way.

  The nicotine in cigarettes is a stimulant, meaning that it increases the function of the nervous system. By acting on the nervous system, nicotine affects the cardiovascular system, enhancing blood flow and raising blood pressure and heart rate. Once you stop smoking, you may experience a decrease in heart rate and blood pressure, according to Dr. Charles Davis, professor at the Department of Health, Wellness and Recreation of New York State University at Fredonia.

Cocaine Use

• According to Dr. Davis, even moderate doses of cocaine may cause an increase in heart rate. Smaller quantities actually depress heart function, while larger dosages poison the heart. BBC News reports that a study by Dr. Murray Mittleman found the increase in heart rate caused by cocaine use also can trigger heart attacks.

Heavy Meals

• Medscape Medical News details a study in which Dr. Francisco Lopez-Jimenez, a researcher with the U.S. Department of Veterans Affairs, concluded that those who already have an increased risk of heart disease are four times more likely to suffer a myocardial infarction, or heart attack, after consuming a heavy meal.