A heart rate that is too low is called bradycardia, and the specific heart rate that is considered not high but too low can vary depending on several factors, including age, overall health, and physical fitness level.
In general, for adults, a heart rate of less than 60 beats per minute (bpm) may be considered too low, but it can depend on individual circumstances. For example, athletes or very fit individuals may have a lower resting heart rate than the general population, and this may not be a cause for concern.
However, if a person experiences symptoms such as dizziness, fainting, fatigue, shortness of breath, or chest pain, along with a low heart rate, it may indicate a serious medical condition and should be evaluated by a healthcare professional. Additionally, in some cases, certain medications, such as beta blockers, can lower the heart rate as a side effect, and this may require adjustment or discontinuation of the medication.