GPS Watches: My How Far We've Come

(This Blog was originally published on The San Francisco Marathon website on 3/22/15)
By Keith Schlottman

Look around you at your next group run or race, and you will notice that nearly every runner is wearing a GPS watch or carrying a GPS-enabled smart phone.  As you run, you may be entertained (or annoyed) by a cacophony of musical beeps and digitized voices alerting the athletes about paces, distances, and even making motivational announcements.  Chances are, if you are a runner, you also bring a GPS along on your run.

Stephanie with her new GPS watch at a TRP group run

It wasn't so long ago that runners ran without GPS.  Although the US began development of the Global Positioning System in the 1970's, the first running watch with a GPS receiver did not hit the markets until 2003.  Prior to then, we used stopwatches to keep time but distances were generally just estimated from a map, or if you were an experienced runner, you might guess at your pace.  In 1984, Timex came out with an LCD watch targeting runners, and the Timex Ironman series dominated runners' wrists for the next couple of decades.

When Garmin released the first few GPS watches, they were bulky and anyone brave enough to wear one received a lot of smirks and oddball comments as fellow runners wondered why someone would use such a funny-looking watch.  I used a Garmin 201, which took up much of my forearm and created an odd feeling of weight imbalance on the run:

My trusty '201 was a bit large

The Garmin 201 also took about 5 minutes or more to acquire a signal, and the charging system was a bulky cable with an RS-232 connection.  But I loved it!  Garmin had an optional software system that you could download the run data to for analysis.  As a bona fide data junkie, this was treasure to me - the ability to examine split details, elevation gains, and distances at such a detailed level was simply fantastic.

Back then the GPS data was far less accurate.  The government actually had a program called Selective Availability which created an intentional error in GPS accuracy, based on the premise that only the military needed precision.  Some claimed that we didn't want the "bad guys" to be able to precisely target a missile strike using the GPS system.  This meant that my data often showed oddities, for example I might run a loop with the same start and finish point, yet the data would say I had climbed 300 feet and finished on the next street over!  Fortunately, in 2000 the SA system was abolished and our running watches are now much more accurate.

My Timex Ironman GPS collected plenty of data

Nevertheless, there is no way to make a GPS 100% accurate, and even with modern tools that attempt to correct for things such as ionospheric shifts and receiver quality, our current running watches will never give a perfect data set.  The error in GPS readings typically ranges around 1 - 2%, which means that when your GPS watch reads one mile, you might have actually gone as much as 50 - 100 feet shorter or farther.  Although current GPS watches often give distance readings to 3 decimal places, you should not treat them as perfect to that level of precision.  The same applies to elevation.  When you run the San Francisco Marathon in July, your GPS will do a fairly good job of showing you how flat the course actually is once you’re done – but it won’t be perfectly accurate.

When you race with your GPS, you will almost always find that your watch shows a different distance than the race's advertised distance.  For example, you might race a 5k, which technically should be about 3.10686 miles, but when you finish your watch displays a different reading.  Be careful about claiming "the course was long", or "the course was short", based on only your GPS.  If the race manager uses their own GPS to measure out the course, you can be certain the distance is off.  But if they obtain USATF Course Certification (and the best races always are Certified distances), the measurement process is different.  In fact USATF regulations prohibit course certification based on GPS.

My latest GPS watch is a Garmin FR620.  It's far lighter and thinner than my previous watches, and has modern features like a touchscreen, Bluetooth and Wifi connectivity - a super toy for a nerd!  But despite the impressive specs, it's still not perfect.  Sometimes the readings are misleading.  The photo below shows a mile split from a track workout in Flagstaff last year, but it does not represent my true mile time - what the watch does not show is that this is a combination of 200 meter speed intervals.

Reviewing mile splits on GPS watches is so easy

There are other limitations as well, including the occasional failure of signal acquisition.  Last year I completed the Boston Marathon only to discover my GPS said I had run only 17 miles - it lost satellite signals partway through the race, and never recovered.  And most runners with GPS have experienced a dead battery more than once.  This is especially true with smart phones, which can fairly rapidly lose power when running continuous GPS.

So they are not perfect, but GPS can be both fun and useful as a training aid.  They can encourage you to run farther - I recall that my first GPS caused me to realize that my regular 3-mile route was actually only 2.8, so I lengthened it.  They can provide a long-term data set to help you understand and objectively observe trends, including mileage as well as pace trends.  The software tools available now are extremely powerful.  Online logging systems like Garmin Connect, Strava, Training Peaks, etc. allow you to analyze the data in ways that would make a mathematician proud.

There are many GPS watch options currently available

There are a few runners out there who will encourage you to “ditch the GPS” and “run naked”, under the theory that the data will spoil your enjoyment of the run.  It’s also possible that excessive monitoring of splits during a run can cause you to actually run slower overall times.  But the GPS is here to stay and it is only going to get better.  In the near future you’re likely to see smaller and more accurate devices, or even perhaps heads-up displays of your data in your sunglasses.  Maybe you’ll be able to monitor teammates’ positions during a race in real time, or have the device alert you when a bathroom or water fountain is coming up.  There are plenty of opportunities for technology advancement in GPS.  The true joy of running comes from the sport itself, and the GPS data is just an additional way to enjoy this wonderful sport.

Keith Schlottman is a 2015 San Francisco Marathon Ambassador who lives in Tucson, Arizona.  He looks forward to testing his GPS accuracy for the 4^th time on the SFM course this year.  If you’d like to join him, use discount code TSFM2015KEITH to save $25!  Keith co-leads the Tucson Runners Project, a free running group for runners of all abilities, with his fiancé.

Running Phoenix

By Guest Blogger Mike Solan

It is 3 AM, February 28th, race day for The Phoenix Marathon. The alarm shrieks, not that I've been sleeping well, and I am wide awake immediately. I feel some trepidation being under trained, having had a big hole in my initial training plan. I try to rationalize that I have a strong aerobic base from bike riding and the enforced “long taper” is to my benefit...well, maybe. The plan is to walk through every other water stop alternating water and Gatorade, and take every gel offered although I am carrying my own, just in case. My goal is 4 hours which according to all the internet pace calculators is achievable based on my half marathon times. We'll see. I've often heard that no plan survives first contact with the enemy (the pavement?), and as someone once told me, “All you have is all you brought, there ain't no more.” So, did I bring enough? (BQ, Boston Qualification, for me is 4:10, but I want some margin for blisters, water, food, potty stops, tears, whatever.....)

I perform the usual pre-race eating, dressing and packing routines (banana, gel, hat, Gatorade, sunglasses, etc.), practiced on every recent Saturday long run. Things immediately go amiss traveling to the drop off. There are roadblocks set up for the race and I don't get to the proper drop off spot (self inflicted – trying to take a shortcut from the hotel). A number of us discover we are in line for the half marathon bus and take a ¾ mile run to the marathon buses as the clock ticks down to 5:30 AM and the last bus. We make it and see five more buses loading behind ours...plenty of time! A pre-boarding warm up run, great! I won't be cold on the bus.

The bus ride to the start takes forever. Where are they taking us, is this a 50 mile run? Off the bus I immediately get in line for the porta-potty.  Afterward, I take a walk around the drop off area, re-lace my shoes for the third time, take off my sweat pants and get in line for the potty again. I get nervous, leave the long line, and head for the weeds. I sit and eat my banana.  The PA call us to walk to the start. Once there, I do some lunges and leg swings. Whoops, time to head for the weeds again, darn Gatorade. I devour a gel and look for either the 3:50 or 4:00 pacer.  Hmm, the 4:00 is quite a bit ahead of the 3:50, what is this? I'm in front of both and decide to stay there. Starting my watch I see a funny screen. It is still dark, I only have my sunglasses and can't really see my watch very well with or without glasses. Somehow it is set to “other activities,” not run. How did that happen?  It gets fixed almost a full minute before the starting gun. Nervous much?

We are off and it is down hill for 5 miles. I keep telling myself to slow down, but only meet with marginal success.  People around me are talking, having a good time, and someone says, “every second above your pace at the start costs you three seconds on your pace in the last half.” Again, I try again to slow down and tell myself there are 26 one mile segments, just take them one at a time and enjoy it.  I listen to some podcasts. I'm saving the running music for the end when I will need a boost. At mile 5 there is a hill, ugh. I try to shorten my stride, lean a bit more forward, and accentuate my arm swings. I pass some folks, some pass me, and some start walking, yikes! There is an aid station with gel at mile 7, but I eat one of mine about mile 6.5. I was hungry and didn't realize the aid station was so close. I eat half of their gel at mile 7 and realize I am over eating, but that doesn't cause me any digestive problems...nervous energy burning calories?

I settle down, steady my pace, and then space out to a Freakonomics podcast. To further distract myself, I think about everyone at TRP I've had the pleasure to run with on Saturdays, trying to convince myself this is just another long Saturday run. That sort of works. I check my watch, change the screen and woops, I need to quickly hurdle one of the cones I'm about to hit.  A person on my left, running in the proper lane, inside the cones, applauds. No blood, no foul I think, but that was close. About mile 10 the 4:00 pacer is now just in front of me and I am determined to stay with her.  However, that means I have to catch her every time I walk through a water stop.  I slip into a mindless groove and pretty soon we are at the half marathon start. I'm feeling good, at this halfway point, but can I do all this again?

Just past the half marathon start, Florence is on the side of the road with a bottle of Perpetuem (Hammer endurance product). I awake up from my mindlessness, just in time to see her and grab the bottle. I carry it to the next water stop, drink about half and toss it. I don't think I needed it, and in the end don't need the additional gels I am carrying either. I'm running along side a graduate student in exercise physiology at ASU and entice her to talk about nutrition. Another young man joins us and we decide to tell jokes to pass the time. Of course at this point I can't remember any really funny ones. I manage to recall one and but tell it poorly (as I tell all jokes). His running mindless methodology is to concentrate on the feet of the people in front of him.  I can't do this well. I imagine how their toes look (as bad as mine?) and don't want to think about that. He stops at the next water stop and we never see him again. No more jokes, darn. About mile 17 the 3:50 pacer group comes around the 4:00 pace group and it gets crowded for a bit.  Quite a few folks try to accelerate and pick up their pace, but for most it proves futile. They fall back but most are then dropped from the 4:00 group also. However my new friend hangs in there with the 3:50 folks and I never see her again.  Soon there are only four runners in the 4:00 pack.

I'm feeling pretty good, staying well hydrated, getting enough calories, but my feet are starting to feel like hamburger, and I know this is costing me a toenail. Heading west on Brown Rd. we have a headwind to contend with. I try to figure out the percentage of the run remaining, but my math skills have deteriorated in direct proportion to the length of this run. I put the music on and try to keep my cadence up as I realize my pace has fallen off a bit.  I cross the 20 mile timing strip and stumble just a bit, but not seriously. I have a talk with myself about staying present and alert for cones, timing strips, etc. I have been running just behind the 4:00 pacer, but she is starting to swing the sign she is holding and I go around her, for safety. Since my longest training run was 20 miles, I tell myself every step is a PR.

I'm counting off the last miles. Five miles is about 45 minutes, plus water stops. It begins to go a bit quicker mentally. Hmm, I might just survive this, and try to imagine it is just like a 5 mile Saturday river path run, Craycroft to Campbell. One last water stop at mile 24. I walk a bit past the stop but chide myself as I am close to my goal time and don't want to lose time walking. At the first barricades, Jeff and Brenda are cheering me, and that lifts my spirits. I think my pace increases ever so slightly. At the finish line I see the clock, a bit over 4:00 (even though the pacer is behind me). BQ, Woot, Woot!!  Florence is at the end of the chute and I kiss her, sweat, snot and all. Jeff meets me in the finish area and is ecstatic with my results. He organizes a picture with both of us, and escorts me to the timer as I hobble along. I am still a bit ditsy. I do realize I have qualified for Boston, finished second in my age group, and am very happy. I have a silly grin for the picture.

At the awards ceremony I have recovered my wits enough to convince my fellow age groupers on the stage that we will not ascend the placement podiums, nor will we stand behind them as suggested. We will instead sit on our respective blocks in deference to our age and accomplishments. This was an easy sell, as even ascending the steps to the stage was hard on all of us.

Still hobbling, I begin dreading the next marathon I had signed up for at the end of May. That was to be my “A” race to qualify for Boston. No need now. However, a few days latter and I'm figuring out training plan adjustments, pacing levels, water stops etc. to take some minutes off my time. Can this be addictive?  Go figure!

Post-race celebration dinner

Lead Out

By Guest Blogger Mike Solan

A couple of years ago, I was suffering from both hypoxia and extreme muscle fatigue after a run up and down Rancho Vistoso Blvd. (and not the full Desert Classic course by any measure). I was no longer standing, but sitting on the curb, and about to assume the prone position by lying on the sidewalk, when I detected someone speaking to me. Amy had asked what my qualifying time was for Boston. “Huh?” was the best response I could muster. Even that took a fair amount of effort in my condition.  Jeff whipped out his smart phone and had the answer as I was still on the ground in agony. “You two must believe in unicorns too,” I wanted to say after I grasped the implication of her question. But I was way too exhausted to do anything but grunt a response, “Ugh!” I hadn't run 10 miles, was flat on my back, virtually in extremis, and the subject now is qualification times for a premier marathon event. Surely I must have left the rational world on this run. Was it on the hard ascent on Rancho Vistoso Blvd or the too speedy descent where I entered this altered reality. When would I return to earth as I knew it? Boston? Really? After a performance like that you link me and Boston? Really?

Time passes, and surprisingly, I live to actually race Arizona Distance Classic Half Marathon. Jeff and Amy go to Boston in 2013 and are through the finish area safely, before the explosion. There are further discussions of Boston qualification, over the next few months, but nothing that I take seriously. To put this in perspective, I will need to take almost 60 seconds off my best half marathon pace, and hold it for twice the distance, to qualify. (Note that this was a full on pace, probably more than everything I had, as I could not step up on a curb after the Desert Classic half. After some kind soul helped me up this particularly challenging curb, my quads locked up and I could not take another step for several minutes, blocking pedestrian traffic.) “Where are those unicorns now,” I am thinking again, as people rush by immobile me.

More time passes. Sometimes I run, sometimes I walk, and sometimes I hobble.  I enter a few races, some go well, some don't.  Sometimes I feel good and hit the finish line feeling strong. At IMS Arizona Marathon in Phoenix I hit the dreaded wall, and then hit the ground (twice, I think), and bleed my way to the finish where I am embraced by a paramedic. Over the next year I encounter hamstring problems, Achilles tendonitis, and plantar fasciitis. Additionally, I seem to hit a plateau with no pace improvements for months. Oh yes, I am now running low on toenails, and vow never to show my feet in public.

In June 2014, a dozen Tucsonans are on a week long bike ride in Colorado. After a moderately hard ride from Creede to Gunnison (105 miles and about 6,500ft climbing) one of the riders changes into his running shoes and asks if I have mine. My answer is “Yes, I have mine right here,” and I hoist a bottle of beer as I endeavor to keep my electrolytes balanced on a daily basis. We had briefly run together at the Meet Me Downtown 5K until he dusted me in the first 1K. When he returns, I hand him a cold one and talk turns to goals and accomplishments. He is anxious to share pain, I'm happy to share a beer.   He had qualified for Boston years ago and wants to do it again. Hmm, I think, I'm beginning to detect a pattern here. Another person thinks I can BQ based on no evidence of ability. However, another beer or two later, “OK, lets do this.”

Returning from Colorado, I look for some running groups that do not interfere with my Tuesday, Thursday, Saturday and Sunday bicycle schedule. I bounce among some groups but mostly what I found were conflicts with my desired biking schedule. Then Amy adds me to the Tucson Runners Project Facebookpage.  With trepidation I attend a Wednesday track session and everyone was very welcoming. With only slightly less trepidation a Saturday run is attempted. Marti and Tom were great to run with.  Other TRP runs are attended, my Saturday bike ride is ditched and a consistent running schedule is developed. Can I work hard enough to Qualify for Boston with TRP? Maybe, but I need a plan.

Time to get serious and figure out how to do this. A literature review is begun consisting of Hanson's Marathon Method, Chi Running, 101 Simple Ways to be a Better Runner, Daniel's Running Formula, Run Faster from the 5K to the Marathon, The Marathoners, 52 Workouts 52 Weeks One Faster Runner, 16 Weeks to a Faster Marathon and Advanced Marathoning. I'm like a kid in a candy store, everything looks good until I read the next good thing. Confusion reigns.  Looking for proof of concept, I try to find out who has succeeded and what did they use. Unfortunately I can't discover a crisp answer, but come to realize no one is going to say, “Do this and you will succeed.” Different formulas will work for different folks.  TRI-FIT has a number of their folks attempting to qualify for Boston and they are using Advanced Marathoning as a basis for a marathon plan, so Advanced Marathoning (the last book I read) it is. Now the task is to rework one of the plans into the TRP running schedule, with a little bike riding and some sort of life other than training and sleeping. Scheduling weekend long runs are easy, Wednesday track can be VO2 max and lactate threshold runs, and Monday PM can be general aerobic conditioning or a medium distance run. But I'm out of week days, recovery runs aren't happening, so I justify easier bike rides as my recovery days and become known as a slacker to my biking friends...grrrr! But I have a plan and my priorities.

In the fall 2014, Saguaro is a great run for me, but A Mountain not so much. So, is this marathon training plan working, only working sometimes, am I destined to be always inconsistent, or am I delusional thinking I can qualify for Boston? I run the Veterans day course with TRP one Saturday, but A Mountain still weighs heavy on me and I do not enter (which I immediately regret the day after the event as you all did so well and seemed to have so much fun).  Next up is the TucsonMarathon. But wait, I'm leaving for Africa the Tuesday after Tucson.  I won't be able to to climb Kilimanjaro unless I'm at full strength and certainly won't be for a few weeks after a marathon. New plan, pass on the Tucson Marathon and sign up for The PhoenixMarathon. 

It is January, 60 days out from Phoenix, and I need to recover that one month hole in my training plan, with most of December spent in Africa.  I can't make it up but need to get back on track.  How will I get those 20 milers in without fear of injury from too much too fast? I fiddle with the training plan and to keep the panic at bay I develop a new mantra, “just run the plan.” I run 18 miles with 15 at my wishful thinking marathon pace. That night I'm in bed before 7 PM and limp for three days afterward. Next week I run 20 miles at an easy pace and my confidence soars. Perhaps I can complete a marathon. Another week, another twenty miler and yes, I can do this, although pace and consequently BQ is questionable.

Three weeks out from Phoenix I have a semiannual dermatology visit scheduled.  Doc says, “I don't like the looks of that,” and out come the surgical steel. Ten stitches in my shoulder later, the instructions are, “…. and no activity for three weeks. You may want to keep your arm in a sling to immobilize it the shoulder.” I gasp, then whine, and negotiate the “no activity” to two weeks, but utterly fail in my attempt to negotiate “no activity” to 10 days. The stitches will be removed the Thursday before Phoenix. Time for a new mantra, “a long taper is a good taper.”  Nevertheless, I cheat. In two days I walk as fast as I can for 7 miles. In 7 days, I'm on my bike and in 10 days I run ten miles at an easy pace. No effort is very hard, just ensuring all the body parts still work as my marathon debut looms ever closer. I keep repeating my taper mantra,“a long taper is a good taper.”...... to be continued.

Pacing a Friend to a BQ at the Phoenix Marathon

By Guest Blogger John Tarantino

I have a friend, Eliot from Colorado, who has been trying to qualify for the Boston Marathon the last couple of years. His qualifying time is 3:15. which he missed by 15 seconds last year at Phoenix.

I'm training for Boston this year and decided I could help pace Eliot and get my 16 mile run in also.

The day before the race we figured out the details. Try to meet between 17 and 18 mile mark.  I would run 6 miles from the finish line and then run 7:15 pace to the end with him.  To get my 16 miles in I turned around at the 26 mile mark and ran out and back a mile.

Day of the race I left the finish line at 7:50am and met Eliot at 17 and a half miles, 8:35am.  Right on schedule!  He had run a little too fast in the first half,1:33, target was 1:36.  We ran together and I was talking the whole way. At Mile 23  Eliot said he was tired.  I dismissed this and told him we had 20 minutes of work to do and he could be tired the rest of the day!! 

At mile 24  I was trying to keep his mind off of being tired and told Eliot to keep an eye on a guy with orange shorts in front of us.

At mile 25 I could feel him slipping.  We saw a lady with a Boston Marathon jacket on and I hollered at Eliot  " Do you want one of those jackets ?

Follow me we are almost there.  Here comes a downhill use it.  I can see the finish line!"  Anything positive came out of my mouth.  He passed the guy with the orange shorts with .1 to go.   Eliot crossed the line in 3:09:51.  This was over a 5 minute PR and of course a BQ for my friend : )

 

John Tarantino

Shelby Twp.,  Michigan