What does 'resting heart rate' measure?

Resting heart rate specifically measures the number of heartbeats per minute when an individual is in a state of complete rest. This measurement is typically taken after a period of inactivity, such as upon waking in the morning before getting out of bed, allowing for an accurate representation of the heart's baseline function without the influence of physical activity or other stressors.

This value is important for assessing cardiovascular fitness and overall health. A lower resting heart rate can indicate a well-conditioned heart that pumps efficiently, while a higher resting heart rate may suggest stress or a less efficient cardiovascular system.

The other options do not accurately describe what resting heart rate measures. While heart rate during vigorous activity and heart rate after a workout pertain to active states, and the average heart rate throughout the day encompasses fluctuations due to various activities, they do not focus solely on the measurement taken at rest, which is the defining characteristic of resting heart rate.