People who work out know the equation well: 220 minus your age is the target maximum heart rate. The formula is a widely accepted standard for gauging exercise intensity that was developed more than 35 years ago. Many exercise machines are even programmed with the formula. However, a group of OU researchers have determined that equation isn’t accurate enough, particularly for those over 50 years of age. Exercising at the appropriate intensity level is important for improving aerobic fitness, especially among people undergoing cardiac rehabilitation for whom optimally restrengthening and reconditioning the heart muscle is critical.

Using data from the now-closed Meadow Brook Health Enhancement Institute, researchers from OU’s School of Health Sciences developed a new model for determining a person’s maximum heart rate.

According to Ron Gellish, research associate in the School of Health Sciences, the original formula was only intended to be a rough approximation and was based on data from a limited number of mostly male subjects under the age of 50. Gellish said the researchers at OU wanted to revise the formula by conducting a more in-depth, longitudinal study approach. They used data from males and females, athletes and those who did not work out much, and younger and older people, and tracked these subjects’ maximal exercise heart rates over several years of testing.

“In developing a formula that intends to show the relationship between maximal heart rate and age, it is far more accurate to look at long-term trends of individuals rather than just a one-time snapshot,” Gellish said. “With the 26 years of data we have from the Health Enhancement Institute, we were able to do a so-called longitudinal study to provide a more accurate formula.”

The OU researchers came up with the formula 207 minus 70 percent of your age. Examining the two formulas, Gellish said the original formula gives the same prediction at 40 years old. However, the 220 – Age equation also overpredicts the maximum heart rate for those under 40 and underpredicts for those more than 40 years old.

“If you aren’t exercising intensely enough, you aren’t adequately conditioning the heart muscle,” Gellish said. “While there are no deadly consequences to relying on the old formula, the new formula will help ensure that anyone working out will be making the best use of their cardiovascular exercise time.”

Other researchers involved with this heart rate research include Brian Goslin, exercise science program director and associate professor; Ron Olson, retired interim vice provost of research; Audry McDonald, graduate student in exercise science; Gary Russi, OU president; and Virinder Moudgil, vice president for Academic Affairs and provost.