heart rate monitor

Hi, I am just a new member, my name is moira and I am 40 years old and I recently had a pacemaker fitted in dec 2008. I normally run marathons, and keep fit. I have started to run again which is great, I normally wear a heart rate monitor but the last couple of days my monitor has said my heart has gone up to 226 which I have never had before then it goes back to normal about 165 has anyone else experienced these problems or do you think it is interference from the pacemaker.

Thanks

5 Comments

HRM

by DonSoule - 2009-05-12 05:05:16

I don't know what type of HRM you use - I know some people have had trouble with them and pacemakers but my RS200 SD works fairly well. I have always had some invalid readings but when I started have more of them I changed my wearlink battery and started using an electrode gel on the contacts and it improved.


Some additional information if you have polar:

Polar Heart Rate Monitor Troubleshooting Checklist
Before you return your Polar Heart Rate Monitor to Polar for service, please check the following:
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?
3. Is the transmitter clean?
4. Is the receiver within one metre 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.
6. Check that there are no other transmitters within one metre if you have a non-coded transmitter.
7. Has the battery been changed by an unauthorised party, causing damage to the receiver?
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 manual for global reset instructions).
10. The chemicals in some swimming pools and seawater may effect the ECG signal pick up.
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.



Why You Might Be Getting Abnormal Heart Rate Readings When Exercising
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.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.

2. Wear and tear of the transmitter

Proper care of the transmitter after use ensures longer service life for the transmitter.

2.1. Wash the transmitter regularly after use with a mild soap and water solution. Dry it carefully with a soft towel after washing.
Never store the transmitter when it is wet. Sweat and moisture can keep the electrodes wet and the transmitter activated, which shortens the battery life.2.2. Store your Polar heart rate monitor in a cool and dry place. Make sure that the electrodes do not contact anything damp, such as sport towel or wet elastic strap. Do not store a wet transmitter in any kind of non-breathing material, such as a plastic bag or a sports bag.

2.3. Do not bend or stretch the transmitter. This may damage the electrodes.

2.4. Only dry the transmitter with a towel. Hard-handed handling may damage the electrodes.

2.5. Keep your Polar heart rate monitor out of extreme cold and heat. The operating temperature is -10 ºC to 50 ºC/ 14 ºF to 122 ºF. Do not expose the Polar heart rate monitor to direct sunlight for extended periods, such as leaving it in a car.

2.6. The transmitter can be washed with mild soap and a gentle brush. If the electrodes appear discoloured, the transmitter needs to be washed. Do not use any alcohol or a solvent based detergent.

3. Electromagnetic disturbances

Electromagnetic disturbances may occur near high voltage power lines, traffic lights, the overhead lines of electric railways, electric bus lines or tram lines, televisions, car motors, bike computers, some motor driven exercise equipment, cellular phones or when you walk through electric security gates. Check your surroundings and move away from the source of interference, or remove the source of the disturbance.

4. The distance between the transmitter and the receiver is too great

The maximum transmission range between the transmitter and the receiver is 1 metre (3 ft). If the distance is greater, the receiver may not get all the signals sent from the transmitter. In cases where the transmission range is at it is extremes, for example rowing or biking where the receiver is not attached to the wrist, the receiver may display the same heart rate for a long time. To avoid this, keep the distance within 1 metre.

5. Signals from more than one Polar Transmitter within 1 metre transmission range
Note only with non-coded transmitter (T31)!

In cases where are more than one transmitter nearer than 1 meter, and you are using the non-coded transmitter, your receiver can pick up the signal from all transmitters within the range, this can result abnormal high readings. Even if the other transmitter is coded, and yours is non-coded, your receiver may still give an inaccurate reading. To avoid signal crosstalk, keep the distance to the other transmitters.

The coded transmitter and receiver system does not pick up the signal from other heart rate monitors. In case of false readings with a coded transmitter and receiver, check if the code has been locked. After a successful code search, a frame will appear around the heart symbol on the display. If the frames around the heart cannot be seen start the measurement again and check that you are not near other heart rate monitor users, because they may interfere the code search. Also, high voltage power lines, televisions, mobile phones and other sources of electromagnetic disturbance may interfere with the code search, as well as keeping the receiver too close to the transmitter.

6. Static electricity, technical sportswear and special conditions

If the humidity of the air is low, or you are exercising in windy conditions (for example high-speed road racing), a fluttering shirt may rub the transmitter and generate static electricity. This causes additional signals, especially if the contact between skin and transmitter is poor. To avoid this:

6.1. Moisten the electrodes before use, or use the conductive lotion or gel
6.2. Use a cotton shirt instead of a synthetic shirt
6.3. Use a tighter shirt to avoid fluttering of the material
6.4. Use the transmitter on a wet shirt
6.5. Wet the shirt

7. Arrhythmia

Polar Heart Rate Monitors are not designed to detect arrhythmia or irregular rhythms and will interpret them as noise or interference. The computer in the wrist receiver will make error corrections, so that arrhythmia beats are not included in the averaged beats per minute. The blinking heart symbol in the face of the wrist receiver, however, will continue to show all heart beats received. In most cases the Polar Heart Rate Monitors will work fine for persons with arrhythmia.

8. Battery of the transmitter is getting empty

The estimated average battery life of the Polar Transmitter is 2500 hours of use. If the battery of the transmitter is running low, the transmission range decreases and may cause errors similar to the ones listed above in this document.

Don

interference

by Tracey_E - 2009-05-12 05:05:35

Many pm's interfere with many hr monitors. A few people here have found ones that work but most of us have not. It sounds like it's picking up your hr as well as the pm spikes. I have the opposite problem- my pm interferes with the hrm and tells it I have no heartbeat. I'm pretty sure I do :o)

The only one I can get a reading on is the Brookstone ring because it uses infrared rather than radio waves, but it's not too accurate when exercising because it isn't a constant monitor but an average. Works ok at rest, tho.

See Your Doctor...

by chip - 2009-05-12 05:05:56


I wouldn’t think that your pacemaker would not interfere with the monitor.

I instead would wonder, if the readings are correct, what was causing the fast heart rate.

Only an interrogation of your pacemaker will tell the true story. With a possible rate of 226 I would call my doctor for advice and an appointment right away.

Better safe then sorry.

HR Monitor Readings

by ElectricFrank - 2009-05-13 12:05:42

Tracy is right on about the problem with HR monitors. The ECG type that use the electrical signal of the heart have a tendency to intermittently count both the ventricular contraction wave and the pacemaker spike that triggered it. If your pacer is providing atrial pacing as well there will be 2 pacer spikes per heart beat. This can result in readings as high as triple the actual heart rate, or as Tracy has experienced the monitor detects something is wrong and quits displaying a reading.

The next time you hit one of those 226 readings take your pulse manually. A reading that fast should be very obvious or maybe weak enough to be undetectable.

frank

Finally

by kprice11 - 2010-01-17 04:01:33

I have been having this same problem for months. I went to see my doctor and everything. I finally gave up and gave the HRM to a friend in my exercise class. I would really like to find on that works with high activity workouts. Let me know if anyone has found one.

New to the site - Thanks.

You know you're wired when...

You have rhythm.

Member Quotes

Think positive and go out and take on the world.