The feeling of a fast-beating, fluttering, or pounding heart is known as a palpitation. Experiencing this sensation during physical activity is a common occurrence that can be unsettling. While the heart is meant to beat faster during exercise, sometimes the rhythm can feel irregular or noticeably forceful. Understanding the difference between a normal response to exertion and a sign of a deeper issue is important for anyone who experiences this.
Common Triggers and Physiological Responses
The most frequent cause of palpitations during exercise is the body’s normal physiological response to physical demand. When you begin a workout, your sympathetic nervous system is activated, releasing catecholamines like adrenaline. This hormone surge increases your heart rate and the force of each contraction to deliver more oxygen-rich blood to the working muscles. The awareness of this stronger, faster heartbeat is often interpreted as a palpitation.
Sometimes, the heart’s electrical system may experience brief, harmless misfires, known as premature atrial or ventricular contractions. These extra heartbeats can feel like a skipped beat followed by a hard thump, which is the heart refilling and contracting forcefully. Up to 40% of endurance athletes show these benign premature beats on monitoring, often exacerbated by a heightened awareness of their heart rhythm during focused training.
External factors also contribute to these benign rhythm changes. Dehydration, resulting in reduced blood plasma volume, forces the heart to beat faster to maintain blood pressure, which can lead to palpitations. Heavy sweating can deplete electrolytes like potassium and magnesium, which are necessary for stable electrical signaling in the heart muscle. Consuming stimulants such as high doses of caffeine or pre-workout supplements shortly before exercise can directly increase heart excitability and the frequency of premature beats.
Differentiating Benign Palpitations from Warning Signs
While most exercise-related palpitations are harmless, some can signal a serious underlying cardiac condition. Palpitations that are brief and resolve quickly as you cool down are typically considered physiological.
A serious concern arises when palpitations are accompanied by symptoms not normal for physical exertion. These “red flag” symptoms include chest pain or discomfort, which may suggest an issue with blood flow to the heart. Disproportionate shortness of breath, severe dizziness, or lightheadedness occurring with the palpitations are also warning signs.
Fainting or a brief loss of consciousness (syncope) is an urgent symptom suggesting an unstable and potentially dangerous heart rhythm. Palpitations that are new, prolonged, or occur with minimal effort, such as while tying your shoes, also warrant a prompt medical review. These symptoms can be linked to conditions like atrial fibrillation, supraventricular tachycardia, or structural heart issues affecting the heart’s electrical and pumping function.
Medical Evaluation and Preventive Lifestyle Adjustments
If you experience concerning palpitations, a medical professional will typically begin the evaluation with a thorough history and a 12-lead electrocardiogram (ECG) to check the heart’s electrical activity at rest. If the palpitations are infrequent, the doctor may recommend ambulatory ECG monitoring, such as a 24 to 48-hour Holter monitor or a longer-term event recorder, to capture the rhythm during a typical day, including exercise.
For symptoms that happen specifically during or immediately after exercise, a stress test may be performed to safely reproduce the palpitations under controlled conditions. An echocardiogram, an ultrasound of the heart, may also be used to rule out any structural heart disease or valve abnormalities. The results from these tests guide the diagnosis and any necessary treatment plan.
If palpitations are deemed benign, certain lifestyle adjustments can help reduce their frequency. Maintaining consistent hydration and ensuring a balanced intake of electrolytes through diet or sports drinks following intense exercise is important. Reducing or eliminating stimulants, including excessive caffeine and nicotine, can lessen heart muscle excitability. Managing stress through relaxation techniques promotes a calmer nervous system, which helps stabilize heart rhythm both at rest and during activity.