I am convinced that I will not be mistaken if I affirm that of all sports inventions, the GPS watch for runners has marked a before and after in the sport.
When these did not exist, the measurements were made by popular runners by eye, so that unless you were running on an athletics track, the measurements would never be accurate.
The garmin GPS watch for runners has marked a point of inflection, but it has also led to believe that it is infallible, when it does not really have an exactitude and there are different factors that distort the measurement.
Before explaining the operation of the clock itself it is important to know what the acronym GPS means and what is the operation of it.
GPS stands for Global Positioning System and was created by the United States in the 1960s for military use only. It is the mechanism with which it is possible to measure the position of an object on Earth with a margin of error, in certain cases, very small.
The GPS system consists of 24 satellites that orbit around the Earth and send information about the position and time, through triangulation.
Apart from the satellites, there is a base station located in the USA, five stations that have the mission to control the signal sent by the satellites and some stations that send data to the satellites.
Finally, there is your GPS watch for runners that is in charge of processing the signals that it receives from the GPS. For getting yourself one check this list of best outdoor watches available.
How does the GPS watch work for runners?
Through triangulation, satellites are able to indicate with a more than notorious accuracy what is the position and time. To do this, they measure the distance that separates each satellite from the measurement point, that is, where you are with your GPS watch for runners.
Although they are used to measure the distance traveled and the pace, sure to finish a popular race have discovered with disgust that you have traveled 500 meters and that your partner has run 100 meters less than you.
Before you start to pester the organization of the race I would like to remind you that they are not as accurate as you think and that the margin of error can be up to 150 meters per kilometer.
That they are not so precise is mainly due to:
The frequency of registrations
In GPS watches for high-end runners the frequency of registrations increases. It is not the same as the records are every second that every 5 seconds, in the second case the GPS clock will show more inaccuracy.
When black clouds appear in a race, you do not just have to hurry to finish the race before the rain falls on you, but you have to assume that your GPS corridor clock will fail.
The signal sent by the satellites will encounter difficulties and your watch cannot receive it correctly, so it is very likely that the measurement is inaccurate.
To participate in a straight race and without curves the margin of error of your watch is less, but this does not apply when the competition has curves.
The GPS watch does not understand curves like you, but it joins in a straight line the last points of registration, if the frequency of records is every 5 seconds and it takes you 5 seconds to enter and leave the curve, the GPS will measure it as a line straight.
Obviously, it is not so extreme, but it serves to give you an idea of how it works.
Buildings, tunnels, and trees
These are the 3 main enemies of your GPS watch since they are the ones that seriously distort the GPS signal. If you run near tall buildings the signal your clock receives will be very distorted and will never be accurate, while if you enter a tunnel or run in a very leafy area the signal can be lost by not being able to cross these obstacles.
I remember running a half marathon where the distance marked by my watch exceeded 22 kilometers, and could not be a failure of the organization to be a homologated circuit. So, in a competition do not trust what your GPS watch for runners.