More on the Garmin elevation correction and WKO+

In my last blog post, I talked about the elevation profile issues with the Garmin 305, but how it can be corrected with WKO+ software. I didn't go into how to do this exactly, because I figured the people at Peaksware would describe it well on their blog, and sure enough, THEY DID!

You can read about the procedure to fix your elevation profile for your run, step-by-step, with pictures to illustrate the process.

http://blog.trainingpeaks.com/2008/01/ground-control-elevation-correction-for-your-gps-device.html

Enjoy!

Vance

Garmin 305 Continued

In my last post, I mentioned how the Garmin 305 Forerunner GPS isn't a perfect tool, but any flaws it has can be accounted for. Here is where I want to discuss them.

The biggest inaccuracies of the 305 is the altitude/elevation profile information. However, it seems to be better when your runs are not completed along the ocean. For some reason, all my runs along the coast end up with excessive errors, claiming I have climbed a few thousand feet in 10K. Clearly, I barely left sea level.

If you're using the new Training Peaks WKO+ software to monitor your running, with rTSS, NGP and IF, you are in luck! You can actually correct the elevation profile of your Garmin 305 files, to get the right data.

How does it do this? WKO+ takes the coordinates of your run, and connects to a database of your choice, (I like the USGS website), to get the exact profile of the run you completed. This becomes very important, because a profile which says you are running more up and down than you are will give you a Normalized Graded Pace which is faster than you actually did. This in turn affects all your other calculations, such as run Training Stress Score, and Intensity Factor.

Just how much of a difference does it make? Here's an example from my run, a 10K loop around the bay and on the ocean, mostly at sea level...

Duration: 45:23

Data from Garmin before correction of elevation profile:

rTSS: 83.8
IF: 1.026
NGP: 6:32
Elevation Gain: 1917 ft
Elevation Loss: 1879 ft
Grade: 0.1 %

Data after correction of elevation profile in WKO+:

rTSS: 77.7
IF: 0.967
NGP: 6:47
Elevation Gain: 255 ft
Elevation Loss: 259 ft
Grade: -0.0 % (-3 ft)

When we examine the data above with more detail, we can see a difference of nearly 1700 ft in elevation profile alone! IN ONLY 10K! This counted for a difference in my intensity factor at the time as being above threshold pace, or below it! That made a difference of 7.3% in Training Stress Score, or in other words, the measured affect of the workout on my body was 7.3% lower than what it said. That's a pretty significant difference in stress on the body!

As I said, the problem seems to be more exacerbated near the ocean, and as I go inland it seems to get better. However, I have not tested this theory, and certainly haven't seen if it is any better or worse at significant altitudes.

So this one example how the Garmin 305 as a training tool is not perfect, but it's inaccuracies can be accounted for.

Next time I will discuss the accuracy of the 305's distance measuring.

Vance

Garmin 305 Forerunner

One of the coolest products I use in my training is the Garmin 305 Forerunner. Honestly, used with the new WKO+ software, you can be more in touch with your fitness and race-preparedness than ever before! And I'm saying this as a runner of over 16 years, who has competed at the NCAA Championships, and some of the biggest races in the world.

This item will really help you to understand better what your economy is, by showing you the relationship between your pace and your heartrate, much like a cyclist uses power and heartrate. If you pay attention to my coaching blog, I will be discussing the importance of this feature, and how it works to keep your training precise and maximize your training time.

The features included in this GPS system include:

• Current and average pace
• Lap recording with lap pace, auto lap recording by distance, (every mile or km), or a lap point on a course
• Distance, with alerts for every mile or km
• Heartrate zone settings, with alerts to keep you in the zones you want to be in
• Elevation, with total ascent and descent per lap and throughout the workout
• For cyclists, it records speed, and will even give cadence with some additional hardware

Is the Garmin 305 a perfect tool? No, of course not. But it is the best tool out there for running, and even it's imperfections can be accounted for, and even while it isn't 100% accurate, it is very consistent!

If you're considering getting one, you can order it here for under $200! (One of the best prices I've seen!):
Garmin 305 Forerunner

In the coming weeks I will discuss the 305, and how to maximize this tool for your training.

Vance