Tuesday, December 3, 2013

GPS Approximations

I recently carried out a USATF certification of the local Turkey Day 5K course. The race promoter wanted the course to have the same start and finish line, so I had to make extra measurements. In fact, I toured the course eleven times to make sure it was as accurate as possible while adjusting for a common start/finish line.

Though I have not kept count, I believe that I have carried out this process more than 150 times dating back to the 1980s. This measurement went smoothly. The temperature remained constant, so six of the eight calibration rides, four before and four after the final three rides, resulted in the same number of clicks. I encountered light traffic, which allowed for tight tangents on the almost constantly arcing course. The three rides on the final course only varied by five clicks. That leaves me quite confident in saying that the race distance over the measured tangents was 3.107 miles with an error of +/- 0.001 miles (+/- 5 ft).

That accuracy and precision was with the Jones Counter. The GPS devices I had with me on those rides resulted in a completely different story. I know this has been chronicled in several articles published in national papers and magazines, but it seems that lot of people have not downloaded their data and then zoomed in on the maps.  That leads them to believe that their prized GPS devices are super accurate, not to be questioned, measuring devices. Sorry. They are not. If they were, the sport federations would allow us to certify courses with them.

Here is a superficial look at how GPS devices work. GPS units receive transmissions from satellites in the GPS network. The receiver and satellite are set up to be in synch, so the receiver (your GPS watch, handheld, auto unit, etc) uses lag time of the satellite signal to determine position. The "Man" lets us have signals that come at time intervals resulting in, AT BEST, an 8-10 meter (25-40 ft) ESTIMATION of where the receiver is at a given time. Please reread that last line. It is important that you have that in mind before you view the satellite map images of my race during that recent 5K.

The shot above seems to indicate that I started on the courthouse steps. I assure you that I was just right of the center of the road. I am impressed with the luck of the two flags being so close together. This is not usually the case.

This second shot proves that I am, in fact, Superman, since I ran straight through two stone and steel walls of the hotel. This bizarre path folks, is the GPS drawing a straight line between two satellite transmissions. The device assumes we travel in straight lines between signal readings, so it often cuts off corners like this. Still, I like the image of me powering through those walls while maintaing pace.

More straight line "curves." This time they indicate that I was taking a shortcut - running through the grass and along the sidewalk. Yep. That's what I did. Shhhh.

The first U-turn. GPS devices have their minor shortcomings, but their largest errors come when there are U-turns or trail switchbacks. The likelihood of the device getting a signal at that pivot point is dependent on speed and, mostly, luck. That means "not very likely." Sure, I saw the cones at the end of the median, but I decided to leap over the median and run straight toward my friend, Jeremy, in a game of chicken. Yeah, that's what I was up to.

The second U-turn. Hey, I got away with it the first time!

The in-race measurement pictured above was 3.06 miles. The corner and U-turn errors seem to easily make up for the .05 mile error.

By the way, the GPS measurements during certification varied between 3.05 and 3.14 miles. That is a difference of 475 ft! (Remember, the Jones Counter had a consistency of about 5 ft)  The route for the longest GPS measurement managed to go beyond one of the U-turns, then had me riding through the river for a quarter of a mile, (Superman. Duh!) and ended beyond the finish line.

The moral to the story is the same one projected in the articles appearing in major publications. Your GPS is a great tool for approximating distances, but it does not measure infallibly. So, please do not use your GPS measurements to tell a race director that their course is too long or too short. You might, instead, ask them if it has been certified with a Jones Counter using the stringent USATF certifying procedure.     ST

Sunday, November 3, 2013

Arizona-Sonora Desert Museum

The day after Du Nats I was fortunate enough to spend seven hours touring the Arizona-Sonora Desert Museum with some amazing people. We arrived early in the morning and strolled more than two miles along the asphalt and gravel pathways while taking in the sights and sounds of a living museum.  The ASDM pays tribute to and offers a short course in the history and livelihood of the vast Sonora Desert which spans a vast area of northwest Mexico and the southwest of the U.S.

The 21-acre facility features more than 1200 native flora species and 230 native fauna species that are in 16 separate gardens throughout the desert landscape that makes up the museum. In other words, there was a lot to see. Enough that we were not able to see a few of the more elusive animals in our day-long visit.

Below are some of the amateur 200+ photos I took with my point and shoot Canon elf. Hopefully, these photos will entice you to spend one of your valuable days exploring and learning the ASDM. You'll be glad that you made the effort. Click and take in a slideshow.

ASDM is short drive from Tucson
Sights near Gates Pass approach
Near Gates Pass
Valley approach near Old Tucson

Enclosed nests were plentiful
A young fasciated saguaro 

Napping beast - even chasing Andy at
the museum proved taxing.
Looking east toward Tucson
This sign needs an update
Oh, we see you!
No, those tattoo numbers are
not easily removed.
Raven in a raptor show.

The owl was miked - she called
to it and the other raptors.
Great horned owl = majestic presence

Red tailed hawk found a friend (dot) and
decided not to entertain us

Snacking otter

Humor in the arachnid room

Immense beauty

Tuesday, October 29, 2013

Du Nats Report

Oro Valley, AZ lies just north of Tucson. It is an alluring place for me. I have loving relatives there who welcome me with open arms.  The valley is surrounded by desert mountains which, of course, means there is a field force pulling and guiding me in. And the valley just hosted the USAT Duathlon National Championships for the third year in a row. It is no wonder then that I found myself in Oro Valley again last weekend.

The journey to the desert was fraught with icy peril. Well, not really, but the mere possibility of icy planes initiated two last minute de-icings that caused the Evansville plane to leave forty five minutes late and then wait another thirty minutes on the O'Hare tarmac while another bird was de-iced at our gate. The result was a nervous hustle over to the connecting flight. The last to board that flight, I felt certain that Hope, my bike of choice for the race, had not made the connection. Twenty hours later a part of me was wishing that she hadn't.

The rest of the day went according to plan. I checked into the hotel next to Catalina State Park, built and tested Hope, went to packet pickup, visited relatives, and had a great pre-race meal. I even got to bed early!

I arrived at the race site early enough to stop by the bike mechanic to have him run through Hope's gear settings since I wasn't happy with the finicky front derailleur. He adjusted the front derailleur screw while I applied sunscreen and put on my race belt. (OMG!! Why did I need 9 numbers, USAT?!) When I looked over at one point I thought I saw him looking at my seat, but I thought nothing of it as I was mentally rehearsing my transitions.

A few minutes later I left the bike in transition - right next to my friend and major competition - Andy Ames. Andy, from Boulder, CO, is a talented athlete and a great guy! Followers of this blog know that Andy has beaten me both times we raced this season. Because my health had almost returned to normal and because my training had indicated that I was significantly faster at both running and cycling than I had been all year, I felt that my chances of beating Andy were as good as they could be.

The plan was simple. I would stay within myself and within 30-35 seconds of Andy on the first run. Then I would bike into the lead with legs that were much stronger than they had been when I had out biked Andy twice before. My cycling was, in fact, better than it had been in several years. So, I planned/hoped to get far enough ahead of Andy to build an insurmountable lead going into the second run. That was the plan, anyway.

All seemed well, as I stood on the start line, but full knowledge of the situation at that moment would have caused me to wet myself!

The first run went well for me. The course consisted of two out-and-backs that both dropped down hills before coming back up to the transition/start area. I was surprised to find myself running in fourth place at the first u-turn, but content as I was comfortable and only four seconds behind Andy.

When I reached the second u-turn, which is about 1200 uphill meters from the end of the run, I was only eighteen seconds behind Andy and in second place in the wave. And I still felt comfortable. I moved cautiously up that last big hill, knowing that I would give up time but also hoping to remain comfortable. I crossed the line in 17:35, which was 17 seconds faster than last year. Groovy!

After a smooth transition I powered up to speed on the slight incline leaving transition. Then I settled in for a fast ride while scanning the crowd of earlier-wave racers until I saw Andy climbing the first of many hills as I descended to the base of that climb.

Not the fastest way to ride.
It was on that first climb, two minutes into the ride, that my chasing of Andy ceased. While I was dropping gears and beginning to push hard on the pedals I felt the nose of my seat move. Not groovy at all! After easing up on the pedals for a few seconds I dug  hard again and down went the seat. I stood up and saw that it was pointing down at about 30 degrees. I yanked it up and sat down to start pedaling again. And down it went again! Grrrr.

Post race . . . 
The Oro Valley is quite hilly, so this up/down scenario played out over and over - dozens of times. My frustration grew when I noted at the first turn around that I had LOST time to Andy. As ridiculous as it may seem, I even tried to hold the seat up with my right hand and steer the bike with my left hand on the aero extension. Boy, did I cuss at that bike as I sought to find a way to ride it fast!

I also started scanning for someone who might have a 5mm allen wrench. I knew that stopping to fix tighten the bolt would cost me 30-45 seconds, but that seemed small compared to the minutes I was losing by not being able to push hard on the pedals, taking pedaling breaks to pull up on the seat, and by trying to pedal from awkward seat heights as that value continuously changed by 2-3 inches. Moving back on the saddle helped a little, but it soon had my lower back screaming at me. I passed the message on to Hope. Oh, how I have grown to hate that frame!

The seat position is a lot more laid back than I am accustomed to, so I had to push the seat fully forward. I have noticed that other multisport athletes have done the same. Kestrel seems to have catered more to the cycling time trialist than to the multisport crowd with the 4000 frame in that respect. To further complicate the problem of moving the seat to the end of its range, the seat binding mechanism is a puzzle of six pieces that are all pressed together when the bolt is tightened. And they do not hold well. I would love to have a talk with the person/team that designed it! I learned early on that the torque required to keep the seat from moving is FAR more than normal. I questioned the company and followed every piece of advice. Still, the seat moved until I created enough friction and torqued the demons of hell out of it. It had not moved on me in several months leading up to Du Nats. Sigh.

Those people who know me well are aware of the fact that I don't really care about beating people. I really do all of this to maintain health. My races are goals that keep me motivated to carry out the consistent training required to keep me fit.

Oh, I am competitive, but I know I am only slightly above average when it comes to innate talent. So, I am used to being beaten by superior athletes like Andy. My top competitor has always been myself. More recently I find myself battling Father Time. Growing old healthily has certainly moved me up in an aging field, but being a fast old man is not good enough. I always want to be fit and to give my best effort.

Because not giving my best is simply unacceptable, that ride was frustrating. Knowing that I should have checked that seat added humility to my vexation. Laughter did find me during the ride, though.

Just after I made the far turn around on the second loop I watched an ambulance pass on the other side of the median. Because I had been pushing hard up to the turn, I needed to pull the seat up. As I stopped pedaling and grabbed it I heard someone screaming ahead. I looked up to see a policeman standing in the road. He was facing me with his arms extended. He was insisting that I stop. I was a mere 50 feet from him and moving at 25 mph. Seriously??? Yes. A fire engine was beginning to cross behind him. Oh, sh@t! I stood there and laughed as I asked the policeman for an allen wrench. Wouldn't that have been an awesome gift?

Glancing at my Polar RCX5 as I approached transition I was crushed to see that my ride had been over three minutes slower than last year and four minutes slower than I thought I could go this year. Tough day in the saddle, hombre!

While running through T2 I found out just how strained my lower back was. The pain took my breath away as I slowly bent over and struggled to put my run shoes back on. I muttered something along the lines of "It's time to go, Princess," as I turned to leave.

I started the second run with relatively fresh legs and an incredibly tight back. Game over. Finishing became my goal. I shook my head as I thought about how much my months-long vision had changed in just over an hour. The race was nowhere near perfect. While I cannot predict whether or not I would have beaten Andy, I am certain that the race would have been more interesting if I had turned a small wrench on that seat bolt.

During my final ascent of the big hill I was able to smile as I thought about the fact that I was a lucky man to be healthy and in such a beautiful place with people who care about me.  And I was thankful for my Polar created data and seemingly endless VFuel energy as I zipped up the top near the finish line.

Post race with Andy
The rest of this AZ trip was magnificent, since it was spent with family and valued friends. We ate big, laughed a lot, and threw stones at Hope.  No, not really. But I thought about it several times as I toured the Arizona-Sonoma Desert Museum the next day. The next post will be a pictorial essay of that memorable day. ST

The view of the Santa Catalina Mountains from John and Lori's backyard . . .