How to set your Polar product to Connect Mode
Polar AXN500 and AXN700:
Press 'Start' (the middle right button) and then down (the lower right button) so that you can see 'Menu CONNECT' on display.

Electrical Interference
Erratic readings on the receiver are usually caused by interference. If the heart rate readings appear to be abnormal, check that your Polar HRM is not within range of other strong electromagnetic signals. Common sources are televisions, computers, bike computers, cars, cellphones, TV antennas, electronic dog fences, high voltage power lines (both above and below ground) and some exercise equipment. Re-locating the position of the wrist receiver can usually solve this problem.

To find a location that has no interference, remove the chest transmitter and exercise as usual. If the heart symbol continues to flash, you are picking up interference. In this case, move the wrist receiver to a location where it does not flash, then replace your chest transmitter. In most cases when the interference is cause by a piece of exercise equipment, placing the wrist receiver on the side rail, away from the front electronics display of the equipment will correct the problem.

Please note: Static electricity in clothing or a flapping shirt can cause electrical interference, so some items of clothing, i.e. man-made fibers, could be the cause. Please try wetting the t'shirt in the area where the transmitter is. You may also reposition your transmitter. Try to shift the transmitter around to the side of your body (try the left side first) or position it lower or higher on the chest. In some cases, you can try the transmitter on your back, however, the belt must then be worn with the Polar logo upside down and facing out. This ensures that the left electrode stays on the left side of the body and the right electrode stays on the right side of the body. Make sure to wet the electrodes every time it is moved to a new position.

You may also try using a water-soluble conductive cream. This will ensure the electrodes are well-moistened.

Trouble Shooting problems with your Polar Transmitters
1. Is the transmitter belt worn correctly? The belt should be flat against the skin, with the Polar logo right side up.

2. Are the electrodes on the transmitter moist? Moistening the transmitter electrodes is essential for good skin contact to obtain reliable and accurate readings.

3. Is the transmitter clean? Regular cleaning of the electrodes is recommended - see Care and Maintenance guide or User manual.

4. Is the receiver within a 3 foot range from the transmitter?

5. Are the heart rate signals very high and abnormal? Relocating the receiver may help. Check the list of sources of disturbances in this document below.*

6. Check that there are no other transmitters within 3 feet if you have a non-coded Polar HRM. Other Polar HRMs can cause inteference.

7. Has the receiver battery been changed by an unauthorized party causing internal damage to the receiver? If not sealed properly, moisture can enter the receiver causing permanent damage to the internal components.

8. Have the buttons been pressed under water, causing leakage in the receiver?

9. If the receiver display is frozen, carry out global reset, if your model has that feature (see the user's manual for global reset instructions).

10. The chemicals in some swimming pools and seawater may effect the ECG signal pick up by the transmitter resulting in abnormal readings.

11. The ECG signal strength varies depending on the individual's tissue composition. The percentage of people who have problems in heart rate measuring is higher in water environment than in normal use.

12. If you are a heart patient, have a second person use the unit under the same conditions and see if the problem still exists.

*Sources of electromagnetic signals can cause erratic and faulty heart rate readings. Such sources include other heart rate monitors, televisions, computers, cars, electric motors, bike computers, mobile phones, antennas, high voltage power lines, electric/invisible fences and certain motor driven exercise equipment. The problem can usually be resolved by relocating the receiver. Static build up in certain clothing can also cause interference.

May I replace the battery in the Receiver myself?
We recommend that you send your heart rate monitor to one of Polar’s authorized service centers, as the receiver should be tested for water resistance using special equipment after battery replacement. However, if water resistance is not a concern, you may take your receiver to a local watch repair shop for battery replacement. Please make sure to inform them that your unit is water resistant.

During the warranty period we recommend that you have the battery replaced by an authorized Polar Service Center only. Warranty does not cover damage or consequential damage caused by service not authorized by Polar. Please call 800-290-6330 for a service center near you.

Abnormal Heart Rate Readings During Exercise
There can be several reasons for abnormal or irregular readings during exercise. Due to the same reasons, heart rate may stay at the same value for a long time or the heart rate stays at zero (0).

1. Poor contact between the skin and the electrodes of the transmitter
For accurate heart rate measurement, the contact between skin and the electrodes should be as good as possible. Polar transmitters measure the ECG signal from the chest, where it is the strongest. The weak heart-generated signals need to be accurately measured before the calculation of the heart rate. It is therefore important to ensure that the contact between the skin and the electrodes is as good as possible.

Here are some tips how to ensure good contact:
1.1. Moisten the grooved electrode areas on the back of the transmitter. At the beginning of the exercise session your skin may be dry and the moisture will help ensure better contact. When you start to sweat the contact will improve because the salt in the sweat conducts the electrical signals very well. Saliva is a good conductor as well. However, if you have a WearLink31 or WearLink W.I.N.D transmitter, it is essential that you moisten the electrodes well under the tap water before the exercise.

1.2. Tighten the elastic strap of the transmitter. If the transmitter is loose, the movement of the electrodes disturbs the detection of the ECG signal. If the standard strap does not fit satisfactorily, larger and smaller elastic straps are available as accessories.

1.3. The type of the ECG signal slightly varies from person to person. The form of the ECG signal can depend on form of the chest, the anatomical location and position of the heart, position of the electrodes and the amount of body fat. If the ECG signal is weak, disturbances can more easily spoil the signal. Find the best contact by turning the transmitter left or right, or place it lower or higher. There have been cases where the transmitter detects the heart rate better when it is turned upside down so that the Polar logo is upside down and facing out, or even when attached on the persons back with the Polar logo upside down and facing out.

1.4. For active sports like aerobics or marathons, women can use the accessory Heart Bra which makes the transmitter stay in place better. Ask your local Polar dealer or distributor for the availability of this product.

1.5. Hairy chest may also weaken the contact. Try to find the best possible position for transmitter.

1.6. In demanding cases, use conductive electrode lotion or gel to improve the contact. After using them, it is very important to wash the transmitter carefully. However, it is not recommended to use conductive electrode lotion or gel when using the WearLink31 or WearLink W.I.N.D transmitter since the lotion or gel can block the electrode area.

Why use a heart rate monitor?

By monitoring heart rate, the simple observation that the harder we exercise, the faster our heart beats is put to good use. Professional athletes and amateurs alike have for decades been relying on the information provided by their heart rate monitor for the following reasons:

1. A heart rate monitor is like a rev counter, giving a precise measurement of exercise intensity.
2. Training at your own ideal pace is made possible with a heart rate monitor.
3. Direct measurement of heart rate during exercise is the most accurate way to gauge performance.
4. Progress can be monitored and measured, increasing motivation.
5. It maximizes the benefits of exercise in a limited amount of time.
6. It introduces objective observation. Are you on the right track? Are you improving?
7. It is a tool for regulating frequency and intensity of workouts.
8. Because of the immediate feedback it provides, heart rate monitoring is an ideal training partner.
How does it work?

When you start training, your heart rate increases rapidly in proportion to the intensity of the training. In Polar Heart Rate Monitors, the transmitter belt detects the electrocardiogram (ECG - the electric signal originating from your heart) and sends an electromagnetic signal to the Polar wrist receiver where heart rate information appears.

The heart moves blood from the lungs (where the blood picks up oxygen) to the muscles (which burn the oxygen as fuel) and back to the lungs again. The harder the training, the more fuel the muscles need and the harder the heart has to work to pump oxygen-rich blood to the muscles.

As you get fitter, your heart is able to pump more blood with every beat. As a result, your heart doesn’t have to beat as often to get the needed oxygen to your muscles, decreasing resting heart rate and exercise heart rate on all exertion levels.

How to determine your maximum heart rate?
You can define your maximum heart rate (HRmax) by:
1. Having it measured clinically in a maximal exercise stress test
2. Having it tested in the field conditions by an experienced coach or exercise physiologist
3. Calculating it by age-based HRmax formulas
4. Use the HRmax-p definition in Polar S-series heart rate monitors

Measured HRmax
The most accurate way of determining your individual maximum heart rate is to have it clinically tested (in a treadmill or bicycle stress test) by a cardiologist or exercise physiologist. You can also measure HRmax in the field conditions in time trials supervised by an experienced coach or exercise physiologist. If you are over the age of 35, overweight, have been sedentary for several years, or have a history of heart disease in your family, clinical testing is recommended.

Predicted HRmax
* Age-based HRmax
There is a mathematical formula that allows you to predict your HRmax. It is called the "age-based formula". The age-based HRmax formula can come in very handy when you cannot take the physician-supervised stress test.

220 - your age = age-based HRmax

For example a 35-year-old person's HRmax would be: 220 - 35 = 185 beats per minute (bpm)

This formula applies only to adults. The generally accepted error in the age-predicted formula is ± 10-12 bpm, which is due to different inherited characteristics and exercise training. If you want to exercise at your most individual and effective levels, your HRmax should be measured.
* HRmax-p definition
Polar S-series heart rate monitors use the HRmax-p definition to estimate your maximum heart rate.
HRmax-p is individually calculated and thus more accurate than the commonly used formula of "220 - your age", especially for very fit people.

A Pacemaker and the Polar Heart Rate Monitor

Persons who have a pacemaker or defibrillator use the Polar heart rate monitor at their own risk. Before starting use, we always recommend an exercise test under doctor's supervision. The test is to ensure the safety and reliability of the simultaneous use of the pacemaker and the heart rate monitor.

The manufacturer of the defibrillator has to approve the simultaneous use of Polar Heart Rate Monitor and the defibrillator.

Technical information about radiated magnetic field of the transmitter:

Polar Non-Coded Transmitter:
Transmission frequency: 5kHz
Means of transmission: On/Off -modulation, magnetic field by means of a 5-7ms burst for each heart beat.
Polar Coded Transmitter:
Transmission frequency: 5kHz
Means of transmission: On/Off -modulation, magnetic field by means of a train of three 5ms bursts for each heart beat Time Interval Coding.

The strength of the magnetic field right next to the transmitter is 5 uT (micro tesla) and 1 nT at 1 m distance. Even in the worst case the radiated power is under 2 nW