So cell phones are supposed to be at their most potent as carcinogens when they are searching for a connection or when you use one while moving (in both instances they have to emit more microwave radiation). Well then, would not the same dangers apply to use of all GPS watches [i.e. exposure to radiation on a day to day basis due to their use while one is in motion]. Might be time to go back to running by feel and/or an old-timey stopwatch.
Can't imagine a device that only recieves signals as being as hazardous as one that transmits, too.
Good thinking, but anything more than 6 inches away from heart'brain'genitals isn't supposed to hurt.
The issue with cell phones is that you are putting a radio transmitter next to your brain. A GPS doesn't transmit anything. It passively receives signals from a satellite.
A Garmin is obviously using a lot more power than a digital watch but I doubt it has any more electromagnetic effect on your body than a plain Timex Ironman or similar watch.
Its the heart rate strap across your chest you have to worry about. All of our best athletes will die of heart cancer - you watch!