This Saturday we have two races, the Mt. Carmel and the Woodbridge Invites.
Since most of our runners will attend one or the other, we’ll have a pasta dinner this Friday at the Mullin’s house.
Quality Training this week will consist of a Tempo plus strides/hill workout tomorrow (I’ll send details later) and a Progressive workout on Wednesday.
Since most of our runners will attend one or the other, we’ll have a pasta dinner this Friday at the Mullin’s house.
Quality Training this week will consist of a Tempo plus strides/hill workout tomorrow (I’ll send details later) and a Progressive workout on Wednesday.
Also, I’d like to take a team photo on one of our recovery days this week. We can do this at Tidelands or at the Del Rocks.
Now for something completely different.
At our 4x1 mile repeats last Friday, I was informed that the mile mark was before the point where I was timing.
Several of the GPS units the kids were wearing “proved” this.
This discrepancy has happened over and over, and I always say the GPS distance is wrong.
I shall now explain why, and hopefully, put this to rest.
You see, a GPS will give you an accurate reading of between 3 and 5 meters 95 percent of the time.
The other 5 percent of the time the reading can be off by as much as 10 meters.
Depending on your GPS and settings a reading is taken, at the most, every second.
This gives you a bunch of points that are connected to determine your distance traveled.
Because of the randomness of the points that are connected, the actual distance recorded by the GPS will always be greater than the distance traveled. You can Google this and find the same info.
Look at the graphic I copied from the link I’ll give at the end.
At our 4x1 mile repeats last Friday, I was informed that the mile mark was before the point where I was timing.
Several of the GPS units the kids were wearing “proved” this.
This discrepancy has happened over and over, and I always say the GPS distance is wrong.
I shall now explain why, and hopefully, put this to rest.
You see, a GPS will give you an accurate reading of between 3 and 5 meters 95 percent of the time.
The other 5 percent of the time the reading can be off by as much as 10 meters.
Depending on your GPS and settings a reading is taken, at the most, every second.
This gives you a bunch of points that are connected to determine your distance traveled.
Because of the randomness of the points that are connected, the actual distance recorded by the GPS will always be greater than the distance traveled. You can Google this and find the same info.
Look at the graphic I copied from the link I’ll give at the end.
The Red Line is the distance the GPS recorded; the Yellow Line is the actual distance.
The Red point-to-point path is longer than the yellow path.
If you measured a mile with a GPS, you would come-up several meters short.
By the way, your time is also a bit overestimated (shows a bit too fast).
When I measure a path, I use the Google Earth measuring tool, which is accurate.
I also have a measuring device on my bike wheel that increments four times every time the wheel goes around.
This has been calibrated against a known distance and is also accurate.
My bike measurement always matches the Google Earth result.
Google Earth lets me set the course on paper, the bike lets me mark points along the course at training, and find the finish when it's not at an easy to find spot along the road.
Google Earth lets me set the course on paper, the bike lets me mark points along the course at training, and find the finish when it's not at an easy to find spot along the road.
Here is the mile path we ran Friday as measured by Google Earth.
To verify the Google Earth’s accuracy, look at the screenshot of our track with both the 100-yard football field and the 100-meter marks for the track.
They’re dead-on.
They’re dead-on.
Still not convinced, read this :-)
http://cincyhalfmarathon.com/-Coach Green
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