I have a confession to make. I get so competitive about heart rates when I am at the gym that my husband will not tell me his.

“How was your workout?” I’ll ask when we get off of Spinning bikes or elliptical cross-trainers. He’ll reply that it was good, he worked at “80 percent.” But 80 percent of what? I want to know what he thinks his maximum is. But he won’t say.

Of course, I know it’s ridiculous to think that a higher maximum heart rate means that I’m a better athlete than my husband. He may have a slower heart rate, but he can beat me in cycling any day. And, after all, the goal in exercise is to get more blood to your muscles. The heart does that by beating faster and by pumping more blood with each beat. If your heart is more powerful, it does not have to beat as fast. “There is no association between maximum heart rate and exercise performance,” said Hirofumi Tanaka, the director of the Cardiovascular Aging Research Laboratory and an exercise physiologist at the University of Texas in Austin.

In fact, Dr. Tanaka said, when people start exercising regularly their maximum heart rate often goes down.