Take out 220 – Age
As a pioneer in fitness training, Sally Edwards, MA, MBA created a cardiovascular training system based on five key heart rate training zones, each built on 10% of your maximum heart rate. The system is popularly known as HZT, Heart Zones Trainng.
The five zones HZT system was first developed and published in 1992 in her work and the first title on heart-rate training, The Heart Rate Monitor Book, and have subsequently been adopted as the standard cardio zones programmed into millions of exercise machines such as treadmills and cycles based on her work.
But according to Edwards, there was a problem with this. It is invalide. The “220 Minus Age” maximum heart rate formula also known as the age-adjusted max formula was first developed in the 1950s by a Stanford medical doctor and accepted by the American College of Sports Medicine.
“There is little disagreement that accurately knowing your maximum heart rate is vital to having a safe, effective cardio training experience, but accuracy is something that ‘220 Minus Age’ cannot get you,” explains the professional triathlete and best-selling author, Edwards. She references Carl Foster, Ph.D., past president of the American College of Sports Medicine, “The 220-age formula designed to predict maximum heart rate is useless, because it simply is not accurate.”
To be clear, it’s not just “220 Minus Age” that’s a problem. Edwards clarifies, “No purely formulaic determinations of maximum heart rate have ever been found to work. Since Robergs and Landwehr’s work in 2002 *We’ve known conclusively that this is the case, yet the industry has not taken action to update our standards to reflect this.
“It’s not like ‘220 Minus Age’ is the only tool we have to determine maximum heart rate,” says Edwards. “There are scientifically validated alternatives that are safe and effective, and they are beginning to get the affirmation they deserve. For 2010, for example, the American Council on Exercise, ACE, is replacing the ‘220 Minus Age’ formula for all of their personal trainer certifications with sub-max testing and other activity based assessments.”
Says Edwards, “Bottom line: the age-adjusted maximum heart rate formula (220 – age = HRmax) should no longer be used by nor should it be recommended by any organization, company, or individual, and I intend to do my part to see that this is so, sooner rather than later.” To that end, Edwards has petitioned various organizations to discontinue the use of the formula replacing it with sub-max field tests.
*“Research since 1971 has revealed the error in HRmax estimation, and there remains no formula that provides acceptable accuracy of HRmax prediction.” Robergs, Robert A. and Landwehr, Roberto. Prediction of Maximal Heart Rate. Journal of Exercise Physiology. Volume 5 Number 2 May 2002. http://bit.ly/1ThD0V