Ironman Fitness IRONMAN 120e, Owner'S Manual

Monitoring Your Heart Rate

Monitoring Your Heart Rate

To obtain the greatest cardiovascular benefits from your exercise workout, it is important to work within your
target heart rate zone. The American Heart Association (AHA) defines this target as 60%-75% percent of your
maximum heart rate.

Your maximum heart rate may be roughly calculated by subtracting your age from 220. Your maximum heart
rate and aerobic capacity naturally decreases as you age. This may vary from one person to another, but use
this number to find your approximate effective target zone. For example, the maximum heart rate for an aver-
age 40 year-old is 180 bpm. The target heart rate zone is 60%-75% of 180 or 108-135 bpm. See 

Fitness Safety

below.

Before beginning your workout, check your normal resting heart rate. Place your fingers lightly against your
neck, or against your wrist over the main artery. After finding your pulse, count the number of beats in 10 sec-
onds. Multiply the number of beats by six to determine your pulse rate per minute. We recommend taking your
heart rate at these times; at rest, after warming up, during your workout and two minutes into your cool down,
to accurately track your progress as it relates to better fitness.

During your first several months of exercising, the AHA recommends aiming for the lower part of the target
heart rate zone-60%, then gradually progressing up to 75%.
According to the AHA, exercising above 75% of your maximum heart rate may be too strenuous unless you
are in top physical condition. Exercising below 60% of your maximum will result in minimal cardiovascular
conditioning.

Check your pulse recovery rate – If your pulse is over 100 bpm five minutes after you stop exercising, or if
it’s higher than normal the morning after exercising, your exertion may have been too strenuous for your cur-
rent fitness level. Rest and reduce the intensity next time.

Fitness Safety

The target heart rate chart indicates average rate zones for different ages. A variety of different

factors (including medication, emotional state, temperature and other conditions) can affect the target heart
rate zone that is best for you. Your physician or health care professional can help you determine the exercise
intensity that is appropriate for your age and condition.

11

(MHR) = Maximum Heart Rate
(THR) = Target Heart Rate

220 - age = maximum heart rate (MHZ)
MHZ x .60 = 60% of your maximum heart rate. 
MHZ x .75 = 75% of your maximum heart rate.

For example, if you are 30 years old, your calculations will be as follows:

220 - 30 = 190
190 x .60 = 114 (low end or 60% of MHZ)
190 x .75 = 142 (high end or 75% of MHZ)
30 year-old (THR) Target Heart Rate would be 114-142

See Heart Rate Table 

(on page 14)

for additional calculations.