The normal heart rate depends on age.
A newborn baby has a normal heart rate of about 120 beats per minute. The fetal heart rate on ultrasound even exceeds 150 beats per minute;
In a baby, it may be physiologically higher than 100;
An adult’s resting heart rate is between 60 and 100. Health and lifestyle affect the heart rate:
A person with a sedentary lifestyle has a resting heart rate of about 80 or more.
An adult with an active lifestyle usually has a resting heart rate of about 60 beats per minute.
When the heart rate is below 60, we are talking about bradycardia, and if at rest the heart beats above 100 beats per minute, we are talking about tachycardia.
Normally, the pulse should be regular. If it is irregular, however, it may indicate various pathologies.
How is the heart rate regulated?
The autonomic nervous system regulates the heart rate. It sends messages to the heart through the sympathetic nervous system (which speeds up the heart) and the parasympathetic nervous system (which slows down the heart).
Therefore, the heart rate will be determined by which system prevails. In a healthy person, the sympathetic system usually dominates during the day, from the moment of awakening, then under the influence of physical activity and emotions it may also speed up. At night, the parasympathetic system predominates, so the rate of beats per minute during sleep may decrease to 30 beats per minute, which explains why we may feel dizzy if we get up sharply at night or after waking up. Constant heart rate variability is a sign of a healthy heart. These rhythm changes prove that the heart is capable of adapting to stress.
If the heart rate is below 60 beats per minute.
Some people are genetically predisposed to a slower-than-normal heart rate. In addition to this, intense exercise explains the low heart rate. For example, a marathon runner may have a resting heart rate of about 40, and this is not a cause for concern. This allows the heart to have more room to accelerate during intense exertion. This bradycardia is not symptomatic.
However, a low heart rate is not always a sign of good health, especially if it is accompanied by symptoms (malaise, shortness of breath on exertion).
A person over 75 years of age with a heart rate below 60 may have an aging electrical circuit in the heart. This may require a pacemaker to be implanted to prevent an attack or syncope (unless the cause of the decreased heart rate is due to medication).
The thyroid gland secretes hormones that also affect the heart rate, resulting in a slower heart rate in the case of hypothyroidism or faster in the case of hyperthyroidism, even in young people.
Some people may experience a sudden acceleration of the heart rate when stressed, followed by an exaggerated slowing or even stopping for a few seconds, resulting in fainting or syncope. This phenomenon is known as vagal or reflex syncope.
Effect of medications
Some patients with coronary heart disease, heart failure, or hypertension may be prescribed medications to slow the heart rate, such as beta-blockers and calcium channel blockers to slow the heart rate or to lower blood pressure.
Potassium deficiency, or hypokalemia, can lead to arrhythmias with an increased heart rate.
A heart rate above 100 is not a sign of good health. It is often a sign of a sedentary lifestyle or an underlying medical condition. When the body adapts poorly to exercise, we speak of dysautonomia, that is, the autonomic nervous system poorly regulates the heart rate and the sympathetic nervous system consistently predominates.
Obesity may also be the cause of increased heart rate.
When a person is anemic, his hemoglobin level is low. In order to properly saturate the organs with oxygen, the heart must compensate by increasing the heart rate.
Heart rhythm disturbances may be related to heart disease. A cardiac examination should be performed. Any cardiac pathology can cause tachycardia.
If there is sudden pain in the chest with palpitations and shortness of breath, a pulmonary embolism can be suspected, depending on the situation, as a blood clot blocking one or more of the pulmonary arteries carrying oxygen-rich blood from the heart to the lungs, resulting in hypoxia. As a result, the heart compensates with a rapid heartbeat.
Dehydration or blood loss
In dehydration or in response to acute hemorrhage, the heart rate increases to provide sufficient organ perfusion.
Psychotropic drugs, medications, and tonics
Alcohol, coffee, cigarettes, and antidepressants increase heart rate.
High temperatures may cause tachycardia. This is the body’s normal reaction to an infection.