heart's stroke volume or your ability to extract oxygen from blood that changes with age, says Sandra Hunter, an exercise scientist at Marquette University in the USA. "It's that your maximum heart rate declines, and no one can change that. It just
's stroke volume or your ability to extract oxygen from blood that changes with age, says Sandra Hunter, an exercise scientist at Marquette University in the USA. "It's that your maximum heart rate declines, and no one can change that. It just plummets