Of all the equipment an exercise enthusiast may need to purchase after their shoes, the most important may be a heart rate monitor (HRM). It can provide constant, reliable feedback regarding the exercise effort. You no longer have to guess your exercise intensity nor do you need to stop and place a finger across the radial or carotid artery to determine your heart rate. This one device can help determine whether you need to step it up or take a day of rest. It can let you know when to slow the pace or whether you are indeed getting more fit.

A heart rate monitor measures the number of contractions of the heart muscle in one minute. This is the basic function of all heart rate monitors. As with the purchase of a car, you may want additional functionality for a higher price.

Heart Rate Monitor Options

There are two main types of HRMs. One includes a chest strap that sends a signal to a watch-like device worn on the wrist. The benefit of this type of device is that it is capable of providing constant feedback. The second type of HRM attaches to a belt. To determine heart rate, you must place your index finger on top of a sensor for a short period of time. The benefit of this type of HRM is that it is usually less expensive. Be sure to investigate how the HRM you are considering works. Some wrist models also operate with fingertip sensor. Investigate whether the HRM will work in all weather conditions. These are some of the options available:

1. Large Character Display - the heart rate feedback will appear on a watch or belt clip. During selection, make sure you can read the display.
2. Continuous Feedback - some HRMs provide constant feedback so you don't have to stop exercising to check.
3. PC Download and software -lets you store heart rate data and then download to a personal computer for later analysis.
4. Stop Watch - times the length of exercise activity.
5. Lap Splits - records length of exercise activity split into periods.
6. Calories Burned - after you enter personal information, the HRM makes calculations based on that data.
7. Time of Day
8. Water Resistance
9. Chest Strap Versus Finger Touch Method.
10. Altimeter - indicates current altitude.
11. Vertical Speed - ascent or descent rate.
12. Barometric Reading - besides barometric pressure, temperature is also measured.
13. Counts Steps.
14. Countdown Timer.
15. Speed/Pace and Distance.
16. Memory Functions to Store Multiple Sessions.
17. Backlight.
18. Compass Features - bearing in degrees, North indicator, cardinal points, bearing tracking function and declination setting.
19. Multiple Users - capable of storing data on more than one person.
20. Global Positioning System (GPS).

Why Use an HRM?

An HRM measures exercise input by counting the number of heart beats per minute. This one number can provide the wearer of all sorts of information but it basically boils down to intensity. Exercising too hard can lead to injury or burnout. Not exercising intensely enough can lead to frustration when you don't see results. The following tips can help you make the most of your device:

1. If you track your waking heart rate over time, a spike of five to fifteen beats could be an indication of overtraining the day before or that you are experiencing the onset of a cold or flu.
2. Taking notice of the heart rate level at a set time period after a workout can indicate whether the workout was too intense.
3. You can create training zones to keep you within a range of intensity, thus guaranteeing the goal of the workout was met.
4. A HRM can be used to indicate when the heart has recovered sufficiently to begin the next exercise period.
5. Maintaining the same average heart rate for a consistent workout over several months can indicate an improvement in fitness. Given identical external environmental conditions, a person should be able to run or walk more efficiently at the same heart rate.

HRM Terminology

Average Heart Rate - the average number of beats per minute measured over the exercise period.

Maximum Heart Rate - the maximum number of beats per minute recommended during an exercise period. There are several formulas for determining HRM. The simplest is to subtract your age from 200. The most accurate is to measure your maximal exercise heart rate using an electrocardiogram (EDG) machine under the supervision of medical personnel.

Resting Heart Rate - number of heart beats at rest, usually measured before getting out of bed.

Heart Rate Reserve - the difference between the Resting Heart Rate and the Maximum Heart Rate. Some training zones use this measure in the calculations.

Target Heart Rate - is the range of heart rate reached during an exercise activity. You get the most benefit from aerobic exercise when your exercising heart rate is 60 percent to 80 percent of your maximum heart rate (220 minus your age). Read more about Target Heart Rate and use a calculator to find your target heart rate.

Age	Maximum Heart Rate	Range
20	200	120 - 160
25	195	117 - 156
30	190	114 - 152
35	185	111 - 148
40	180	108 - 144
45	175	105 - 140
50	170	102 - 136
55	165	99 - 132
60	160	96 - 128
65	155	93 - 124
70	150	90 - 120

* Based on the 220 - Age formula.

Recovery Heart Rate - the number of beats per minute the heart will decrease to after an exercise session.

Training Zones - various ranges of heart rate percentages used to specify training goals such as warm up, fat burning, endurance training, performance training or maximum effort.