A heart rate of 90 beats per minute is normal, and a normal person’s heart rate is usually measured at 60-100 beats per minute when quiet. The normal human heart rate originates from the sinus node and is called tachycardia when it is greater than 100 beats/minute and bradycardia when it is less than 60 beats/minute. Tachycardia can be caused by exercise, stress, fever, hyperthyroidism, anemia, etc., while bradycardia can be seen in athletes, the elderly, hypothyroidism, or as a result of taking beta-blockers. If the heart rate is 90 beats per minute when measured, it means the heart rate is normal. However, if you have coronary artery disease, angina pectoris and heart failure, your heart rate should generally be controlled at 55-60 beats/min to prevent disease progression and reduce myocardial oxygen consumption. It is recommended to maintain a good daily routine and not to stay up late. Eat more fresh vegetables and fruits for balanced nutrition. Moderate aerobic exercise can be performed daily to enhance physical fitness.