POLAR S725 - Manual (Page 14)

A 12
mobile phones may cause interference when starting
the heart rate measurement.
4. Press the OK button to start measuring your heart rate.
A heart symbol will start flashing and your heart rate
(beats per minute) will appear in a maximum of 15
seconds.
5. Press OK again. The stopwatch starts running and you
can start exercising. The exercise data will only be
stored in a file if you have turned the stopwatch on.
How to stop measuring your heart rate
1. Press the stop button. The stopwatch and other calculations stop.
The heart rate measuring continues, although exercise data is no longer
recorded.
2. Press the stop button again. The heart rate measuring stops.
The wrist unit shows the Time of day display again.
After exercising
1. Carefully wash the transmitter with a mild soap and water solution.
2. Rinse it with pure water.
3. Dry the transmitter carefully with a soft towel.
4. Store the transmitter in a clean and dry place. Dirt impairs the elasticity
and functioning of the transmitter. Sweat and moisture can keep the
electrodes wet and the transmitter activated, which shortens battery life.