HRmax

 

Principle

 

HRmax is the maximum heart rate (HR) that a person should achieve during maximal physical exertion. Research indicates that it is most closely linked to a person's age; a person's HRmax will decline during live. The speed at which it decline over time is related to fitness: the more fit a person is, the more slowly it declines.

HRmax is measured during periodically increase of the intensity of exercise (for instance, when a treadmill is being used through increase in speed or slope of the treadmill, or by interval training) until the subject can no longer continue, or until certain changes in heart function are detected in the ECG (at which point the subject is directed to stop). Typical durations of such a test range from 10 to 20 minutes.

There are many prediction equations for HRmax. One of the most precise prediction equations, published in a meta-analysis (ref. 1), is:

  HRmax = 208- 0.7 x age (beats/min),

where age is in years.

It is independent of sex.

It is slightly too high for people performing frequently endurance sport (a decrease of ¾ point per hour endurance sport/week with a maximum of 10 points). The equation yields probably too high values for people older than 65 years. (A reduction of 1 point for every year above 65 seems likely). People who have participated in sports and athletic activities in early years will have a higher HRmax than those less active as children.

 

 

Application

 

HRmax is utilized frequently in the fitness industry, specifically during the calculation of target heart rate (ref. 2) when prescribing a fitness regimen.

 

References

1 Tanaka H,  Monahan Kevin D and. Seals  DR Age-predicted maximal heart rate revisited2001J Am Coll Cardiol 37, 153-156.

2 Wikipedia