What is the normal sinus rhythm range for adults?

• A. 50–90 bpm
• B. 70–110 bpm
• C. 80–120 bpm
• D. 60–100 bpm

Answer: (D)

Normal sinus rhythm means the heart’s beat is generated by the SA node with a regular rhythm. In adults at rest, the typical heart rate that fits this rhythm is 60–100 beats per minute. This range indicates the impulse is originating from the SA node and the rhythm is regular. Rates below 60 can be normal for some well-trained individuals, but they’re considered bradycardia when seen in the general adult population. Rates above 100 at rest indicate tachycardia and warrant clinical evaluation. The other ranges fall outside the standard resting range for adults, so they’re not the normal sinus rhythm range.