Why a Smaller Pump Needs a Quicker Rhythm
The heart has to deliver enough blood each minute to supply the body with oxygen. That total flow is called cardiac output. It depends on two things: how much blood leaves the heart with each beat and how many times the heart beats in a minute.
On average, women have smaller hearts and pump less blood per beat. A faster resting rhythm helps make up the difference, keeping blood moving without requiring each squeeze to match the volume produced by a larger heart. The heart is adjusting one part of the equation to maintain the overall flow the body needs.
Averages, Not Individual Rules
Heart size is only one influence on pulse. Body size, fitness, age, stress, temperature, medication, and other factors can all change how much blood the heart moves or how quickly it beats. The averages for women and men overlap, so a woman’s resting pulse is not automatically higher than every man’s—or fixed at one particular rate.
Training can shift the balance, too. With regular endurance exercise, the heart often becomes more efficient at pumping blood with each beat. It may then meet the body’s needs with fewer beats at rest. That is why a faster resting pulse, by itself, does not tell the whole story about how well a heart is working.
