A high pulse, medically called tachycardia, is a resting heart rate above 100 beats per minute. A normal resting heart rate for adults falls between 60 and 100 bpm, so anything consistently above that upper boundary is considered elevated. A high pulse can be completely harmless and temporary, or it can signal an underlying problem that needs attention.
What Counts as a High Pulse
The 100 bpm threshold applies when you’re sitting or lying down, awake, and haven’t been exercising. Your heart rate naturally climbs during physical activity, stress, or excitement, and that’s expected. The concern starts when your heart is beating fast while you’re at rest and doing nothing to provoke it.
Context matters. A resting heart rate of 105 after three cups of coffee is different from a resting heart rate of 105 every morning for a week. Fitness level also shifts the picture significantly. Athletes and highly active people often have resting heart rates in the 40s or 50s because their heart muscle pumps more efficiently with each beat. For someone like that, a rate of 90 might feel unusually high even though it’s technically within the normal range. Research from the American Heart Association has found that a higher resting heart rate correlates with lower physical fitness, higher blood pressure, and higher body weight.
Normal Heart Rate by Age
The 60 to 100 bpm range applies to adults and adolescents 13 and older. Children and infants have naturally faster heart rates. Newborns up to 4 weeks old have a normal resting range of 100 to 205 bpm. Infants from 4 weeks to 1 year fall between 100 and 180 bpm. Toddlers (ages 1 to 3) range from 98 to 140, preschoolers from 80 to 120, and school-age children (5 to 12) from 75 to 118 bpm. So a heart rate of 130 in a 2-year-old is perfectly normal, while the same number in a 30-year-old is elevated.
Common Causes
Most episodes of a high pulse are temporary and tied to something obvious. Caffeine, nicotine, and alcohol can all push your heart rate up. So can dehydration, poor sleep, stress, anxiety, and fever. When your body temperature rises even one degree, your heart speeds up to help cool you down. Certain medications, including decongestants and some asthma inhalers, can have the same effect.
More persistent causes include anemia (when your blood carries less oxygen, your heart compensates by beating faster), an overactive thyroid, and chronic conditions like heart disease or lung disease. Pregnancy raises resting heart rate too, especially in the second and third trimesters, because the heart is pumping a larger volume of blood.
What a High Pulse Feels Like
Sometimes you won’t feel anything at all. Mild tachycardia can go unnoticed, especially if it comes on gradually. When symptoms do appear, the most common is palpitations, that fluttering, pounding, or racing sensation in your chest or neck. You might also feel lightheaded, short of breath, dizzy, or unusually fatigued. Some people describe a sense of anxiety or unease they can’t explain, which turns out to be driven by their heart rate rather than their thoughts.
If a high pulse comes with chest pain, fainting, or severe shortness of breath, that’s a different situation entirely. Those combinations can indicate a dangerous heart rhythm or reduced blood flow and require immediate medical attention.
Types of Tachycardia
Not all fast heart rhythms originate in the same part of the heart, and where they start determines how serious they are. Supraventricular tachycardia (SVT) involves faulty electrical signals in the upper chambers of the heart. It tends to occur in younger people and is generally less severe. Many people with SVT experience sudden episodes that start and stop on their own.
Ventricular tachycardia (VT) originates in the heart’s lower chambers, which do the heavy lifting of pumping blood to the body. VT is more common in older adults with existing heart disease and can be far more dangerous. It has the potential to degenerate into life-threatening rhythms if not treated.
How It’s Diagnosed
The first step is usually an electrocardiogram (EKG), a quick, painless test where sensors are placed on your chest to record the heart’s electrical activity. An EKG can reveal whether your heart rhythm is normal, too fast, or irregular in a pattern that points to a specific type of tachycardia. Some smartwatches can now perform basic versions of this test.
The challenge is that a high pulse often comes and goes. If your EKG looks normal at the doctor’s office, you may be asked to wear a Holter monitor, a portable device that records your heart rhythm continuously for 24 hours or more while you go about your day. For even more intermittent episodes, an event monitor lets you press a button when you feel symptoms so the device captures that exact moment. Some newer models detect and record irregular rhythms automatically.
Your doctor may also order an echocardiogram, which uses sound waves to create images of your heart’s structure and blood flow. This helps identify whether an underlying structural problem is driving the fast rate. In cases where fainting is involved, a tilt table test can evaluate how your heart and nervous system respond to changes in position.
Risks of a Chronically High Pulse
An occasional spike in heart rate isn’t harmful. But a resting heart rate that stays elevated over weeks or months forces your heart to work harder than it should. Over time, this extra workload can weaken the heart muscle, a condition called tachycardia-induced cardiomyopathy. The heart becomes less efficient at pumping blood, which can lead to heart failure if the underlying rhythm problem isn’t corrected.
A persistently fast heart rate also increases the risk of blood clots, particularly in certain types of tachycardia where the upper chambers of the heart quiver instead of contracting fully. Blood that pools in those chambers can clot, and if a clot travels to the brain, it causes a stroke. The risk of fainting and falls also rises, especially in older adults.
Lowering Your Heart Rate
If your high pulse is tied to a lifestyle trigger, the fix is often straightforward. Cutting back on caffeine, staying hydrated, managing stress, and getting consistent sleep can all bring your resting rate down. Regular aerobic exercise is one of the most effective long-term strategies. As your cardiovascular fitness improves, your heart pumps more blood per beat and doesn’t need to beat as often at rest.
For immediate episodes, vagal maneuvers can sometimes slow a racing heart. These include bearing down as if you’re having a bowel movement, splashing cold water on your face, or coughing forcefully. These actions stimulate a nerve that helps regulate heart rate and can interrupt certain types of tachycardia on the spot.
When tachycardia is caused by a medical condition like thyroid disease or anemia, treating that condition typically resolves the fast heart rate. For structural or electrical heart problems, treatment ranges from medications that control heart rhythm to procedures that target and correct the misfiring electrical pathways in the heart. The approach depends on the type of tachycardia, how often it occurs, and how severe the episodes are.