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The Polar A300 is designed to measure heart rate and tell your activity. No other use is intended or implied.

The training device should not be used for obtaining environmental measurements that require professional or industrial precision.

Interference During Training

Electromagnetic Interference and Training Equipment

Disturbance may occur near electrical devices. Also WLAN base stations may cause interference when training with the training device. To avoid erratic reading or misbehavior, move away from possible sources of disturbance.

Training equipment with electronic or electrical components such as LED displays, motors and electrical brakes may cause interfering stray signals. To solve these problems, try the following:

  1. Remove the heart rate sensor strap from your chest and use the training equipment as you would normally.
  2. Move the training device around until you find an area in which it displays no stray reading or does not flash the heart symbol. Interference is often worst directly in front of the display panel of the equipment, while the left or right side of the display is relatively free of disturbance.
  3. Put the heart rate sensor strap back on your chest and keep the training device in this interference-free area as much as possible.

If the training device still does not work with the training equipment, it may be electrically too noisy for wireless heart rate measurement. For further information,

Minimizing Risks When Training

Training may include some risk. Before beginning a regular training program, it is recommended that you answer the following questions concerning your health status. If you answer yes to any of these questions, we recommend that you consult a doctor before starting any training program.

  • Have you been physically inactive for the past 5 years?
  • Do you have high blood pressure or high blood cholesterol?
  • Are you taking any blood pressure or heart medication?
  • Do you have a history of breathing problems?
  • Do you have symptoms of any disease?
  • Are you recovering from a serious illness or medical treatment?
  • Do you use a pacemaker or other implanted electronic device?
  • Do you smoke?
  • Are you pregnant?

Note that in addition to training intensity, medications for heart conditions, blood pressure, psychological conditions, asthma, breathing, etc., as well as some energy drinks, alcohol, and nicotine may also affect heart rate.

It is important to be sensitive to your body’s responses during training. If you feel unexpected pain or excessive fatigue when training, it is recommended that you stop the training or continue at a lighter intensity.

Note! If you are using a pacemaker, defibrillator or other implanted electronic device, you can use Polar products. In theory interference to pacemaker caused by Polar products should not be possible. In practice no reports exist to suggest anyone ever having experienced interference. We cannot however issue an official guarantee on our products’ suitability with all pacemakers or other implanted devices, such as defibrillators, due to the variety of devices available. If you have any doubts, or if you experience any unusual sensations while using Polar products, please consult your physician or contact the implanted electronic device manufacturer to determine safety in your case.

If you are allergic to any substance that comes into contact with your skin or if you suspect an allergic reaction due to using the product, check the listed materials in Technical Specifications. To avoid any skin reaction to the heart rate sensor, wear it over a shirt, but moisten the shirt well under the electrodes to ensure flawless operation.

The combined impact of moisture and intense abrasion may cause color to come off the heart rate sensor’s surface, possibly staining clothes. If you use perfume, suntan/sunscreen lotion or insect repellent on your skin, you must ensure that it does not come into contact with the training device or the heart rate sensor. Please avoid clothing with colors that might transfer onto the training device (especially training devices with light/bright colors) when worn together.