The Latest 180-Formula

A personalized exercise HR for optimal performance based on your health and fitness levels

Dr. Phil Maffetone

There have been various 180-Formula updates over the past 45 years. Originally, I created this heart rate approach to help people lose excess body fat. It quickly was evident that injuries in those who exercise at this HR resolved faster. I soon realized that this method could help improve overall human performance from brain to toes. 

A boon for competitive athletes and everyone else who works out, and replacement for the old 220-formula, over the years the 180-Formula’s fine-tuning more easily allowed individuals to obtain an optimal exercise HR based on their particular needs. It mimics how I worked one on one with professional athletes, and also corresponds to laboratory measures of fat burning, aerobic and ventilatory thresholds, and other measures. Most important is to consider key health factors and fitness history when calculating your personal exercise HR. 

The 180-Formula posted below is the latest version. It appeared in a paper on maximum aerobic function (MAF) I wrote with Professor Paul Laursen and published in the journal Frontiers in Physiology . This version of the Formula emphasizes vital features we should not forget, otherwise the resulting training HR can be too high to reap aerobic benefits like fat burning, muscle balance, improved endurance, and many others.

When calculating your HR, the condition of overfat is important to consider, and something we can’t make assumptions about. Unless you’ve had a DEXA scan lately, an accurate approach is the waist-to-height ratio. For normal healthy body fat, the waist, measured at the level of the belly button, should be less than half your height. Being overfat puts you in the Formula’s category 2b.

Another important condition in the latest Formula is overtraining, both acute and chronic forms. It’s not easy to accept to the possibility of an impaired hypothalamic-pituitary-adrenal (HPA) axis, which may be the earliest stage of overtraining. These apply to the categories 2b and 2a, respectively. 

Dietary stress can ruin exercise results regardless of HR. The problem, of course, is refined carbohydrates, including sugar, which impairs fat burning and the aerobic system—even very small amounts for many people.

As you carefully read through the Formula below, an honest evaluation will guide you to determine a personalized training HR based on your level of health and fitness. If in doubt about the calculations, choose the result with the lower HR. 

The good news is that as you eat and train well, your performance will improve over time at the same HR. The MAF Test  is the best guide—if it’s not improving or plateaus too soon (within about six month) either your HR or carbohydrate intake—or both—is too high. As improvements in health and fitness are realized, you can raise the training HR, such as when body fat normalizes, overtraining resolves, or medication is no longer necessary.

If you’re happy with the results of your current exercise, competition, body fat, or other factors, you’re right on. Otherwise, please reassess your approach. Discipline is one of the most important features in getting the most from every minute of exercise. It’s not about just doing it…but doing it right.