I am helping a female, 40 years old, with her athletic goals. I am a combination of endurance athlete (1/2 ironman distance) and high intensity weight training. I was running with this person ~11 minute miles the other day, and her heart rate was 188. She is 5'-9" tall, very fit, and does weight training and some cardio. Her goal is to do endurance athletics, so I interoduced her to Dr. Phil Maffetone 180-age heart rate training tro improve cardiovascular function. My own experience is reduced heart rate(`50 bpm) and progressively more strenuous activity at lower heart rates (I am 46 years old). I am interested in how a doctor would feel about my direction to her vs high intensity anearobic training she does. Will anearobic training reduce her heart rate over time? Or is this even something to be concerned with?