Review: Garmin Forerunner 310XT

I recently purchased a Garmin Forerunner 310XT training device for use while running, cycling, and hopefully swimming. The Forerunner 310XT is a new device from Garmin, and their first multi-sport device that is waterproof and can be used for swimming, and thus triathlons.

For the past several years I have been using a Polar S725X multi-sport training device for both running and cycling. The rest of this review will compare and contrast to the Polar device since that is what I am most familiar. I have not used other GPS-based training devices before, so comparisons with those are left as an exercise for the readers.

The 310XT uses GPS to calculate your location and speed. You can then upload your data via your computer to Garmin’s Connect website, Garmin’s Training Center software, or other third-party options. After uploading you can view a map of your route, categorize and describe your activity. With the Connect website, you can easily share your activity via variety of methods, and even export the route into Google Earth.

Like most of Garmin’s training devices, you can pair the 310XT with a variety of other devices that communicate using the ANT+ Sport protocol. The 310XT will receive and record data from heart-rate monitors, bicycle speed & cadence sensors, foot-pods, and even power meters such as the PowerTap. The collected data is then joined with your route data and transmitted along with it.

The bicycle sensor option from Garmin is a combination speed & cadence sensor that mounts on the rear chainstay. This design allows one sensor unit to have two separate magnets for both the crank and the rear wheel. Compared to the Polar solution, this is much cleaner and easier to mount than two separate sensor units. The Polar cadence sensor, especially, is difficult to mount on some of the modern carbon downtubes, so the Garmin solution is a welcome change.

The speed sensor augments the GPS data so that accurate speed is recorded even when GPS signal is not available or accurate.  Garmin also sells an optional foot pod sensor that accomplishes the same when running without GPS signal, such as inside on a treadmill. I haven’t used this sensor yet as where I have run has had great GPS reception thus far.

I used a foot pod sensor with my Polar to keep track of my speed and distance while running. The downside of this type of solution is the relative inaccuracy of the data. I’d often see 10 to 20% margin of error, even after calibrating the foot pod.

My concern with a GPS-based training device would be the accuracy of the signal, especially when running under under a lot of foliage. So far, the 310XT has proven itself more than capable in this regard, and much better than other GPS devices I have used in the past. Viewing the recorded route data I’ve found very little error in position so far, and only a little bit with elevation, even when running underneath trees and bridges.

Like all GPS devices, the 310XT must determine its position when it is powered on. If you start up the 310XT inside, or where there is poor GPS signal, it can take a very long time to determine initial position, if it all. This can be an annoyance when you’re ready to start your training and you don’t have a solid 3-dimensional fix yet. The 310XT lets you begin your timer and start your activity before it has GPS signal, but it can sometimes take surprisingly long to get that initial fix. Another disadvantage of not having a fix is you won’t have accurate local time until then, either.

The Garmin 310XT has a rechargeable battery, but battery life is only approximately 20 hours of usage. My Polar S725X, by comparison, has a watch-style battery that has lasted over 5 years. In practice, a rechargeable battery solution works great, but may present a problem on multi-day activities where there is no opportunity to recharge.

Transmitting the data from the training device to your computer is done via a USB dongle that uses the ANT protocol. Garmin provides drivers and software for both PCs running Windows and Macs running OS X. The Polar solution uses an infrared based receiver that is much more difficult to work with as it requires line of sight between the training device and the infrared receiver, and Polar does not provide a software option for Macs.

For most users, Garmin’s software solutions are stellar compared to Polar’s. The big win here is Garmin’s Connect website which allows you to easily view your data online, share it with friends, and upload your data from a variety of different computers. Sharing your data is trivial, and allows your friends to view your routes, as well as being able to search for routes from others near you. The Connect website represents a modern solution for the social Internet, a great solution for most users.

Where the Polar software shines is for advanced heart-rate based training, especially with coaching assistance. Polar’s software is designed to easily share your data with a coach and receive training programs with them. Additionally, both the software and the Polar device have much more advanced features for heart-rate based training. For example, with the Polar I can run several tests to determine if I am over-training, or even what an estimate of my current VO2max. The Garmin solution only has different heart rate zones, more than adequate for most users, but you do get the impression the Polar has more science behind it.

The 310XT supports multiple bike settings, each with its own odometer. I find this feature in particular compelling as I like to keep track of my mileage for each bike separately, and as far as I could tell the Polar S725X always combined bike mileage for all bikes it had configured, rather than a separate odometer for each one. With the GPS based tracking, you don’t even necessarily need a speed/cadence sensor and you can still keep track of your bike’s mileage. This is especially compelling for mountain biking, where the rough trails often render a traditional bike computer useless.

So far, the Garmin Forerunner 310XT has been a fantastic training tool and I haven’t missed using the Polar S725X yet.

My Houston Marathon Experience

On January 18th, 2009 I ran the Chevron Houston Marathon – my first full marathon – and finished in 4 hours, 54 minutes and 42 seconds.

The Event

2009 Chevron Houston Marathon Course Map
2009 Chevron Houston Marathon Course Map

The full and half marathon events began at the same time with groups separated into two waves. The second wave, which I was in, began 10 minutes after the first wave. The half marathon group started a block away from the full, but joined back up at mile two.

Both the full and half marathon events start and finish at Houston’s George R. Brown Convention Center. The course winds through The Heights neighborhood, through the Montrose district, meanders through the Rice University area, leaves the loop 610 boundary for The Galleria and Tanglewilde districts before turning to downtown via the Memorial Park area.

My plan was to find the runners in the 4 hour, 15 minute pace group and stick with them throughout the run. I intended to use the Jeff Galloway technique of running a few minutes followed by a brief walk. At my pace, he recommends a 4 minute run followed by a 1 minute walk. This pattern is supposed to be repeated until approximately mile 18 where you can then turn on the steam and finish strong. In theory, that is.

As it turned out, I immediately lost sight of my pace leaders even though I was perhaps only 25 yards behind them at the starting gun. The sheer mass of people made it difficult to go the full pace for the first three miles. The massive crowd also made it difficult to start the run/walk cycle right from the beginning, although I did pick it up around mile three.

Between miles 5 and 6 we ran in The Heights neighborhood, and right along the two streets that border my parents’ street, so they came out to see me run past. About this point I ran into – no pun intended – a few of the runners from my running group that run about the same pace I do in training. I started maintaining a running pace that stayed with them and we each began to push the pace a little faster as the crowd thinned out some. This is telling from the result data… over the first 6.2 miles I averaged 5.9 mph or a 10 minute, 7 second per mile pace. During the next 6.2 miles my average pace was 6.0 mph or a 9 minute, 57 second per mile pace – right where I wanted to be.

At mile nine, in the Montrose district, the half-marathon group reached their turn-around point and suddenly the streets became a whole lot less crowded. The spectators thinned out as well, although still remained thick and loud throughout most of the remainder of the course when located on residential streets. The effects of a cheering crowd in an event like this cannot be underestimated. All of the runners have their names printed on their bibs, so you literally have thousands of people calling out your name as you run by; never underestimate the power a flirting woman cheering a name can have on the competitive male psyche!

Almost Halfway
Almost Halfway

I finished the first half of the marathon within 30 seconds of my previous two half marathons I ran in October. That lifted my spirits but fatigue began to set in a few miles later. Just after the 14 mile point we turned onto Westpark and climbed a very large overpass. We also left the residential neighborhoods for a few miles so the combination of the distance, lack of cheering and fatigue of the hill climb finally got to me and I dropped off the pace. The next seven miles proved the most difficult of the race; during my 13.1 to 18.6 mile split I averaged only 5.3 mph or an 11 minute, 18 second per mile pace.

At around the 18.6 (30K) mile point to mile 20 I reevaluated how I’d run the rest of the course. Unlike many of the training runs, I had not bonked but rather muscle fatigue had set in. I decided to take it easy, concentrate on finishing well, and walk as much as I needed to. I did find that keeping a relatively fast running pace felt better than a slower one, but I had to walk much more often to recover. As a result, my last split time was only an average of 4.5 mph or a glacial 13 minute, 17 second per mile pace.

Around mile 20 the race officials also changed the flag risk from green (run as planned) to yellow (ensure adequate fluids and cooling; slow pace as heat increased) as the temperature approached 70 degrees. It really was a near perfect weather day, except runners would really prefer it to be 20 or 30 degrees cooler than that for racing.  I felt comfortable and cool enough, but noticed I was running slower with the same heart rate as I was earlier in the day (which I try and keep between 160 and 165 during a race).

During the last three miles the head coach of my running group, along with the coach of my pace group and several other members of the group caught up to me and did their best to encourage us to keep up and finish strong. I picked up the pace for a little while but fatigue won out and they wound up passing me around mile 25. In the end they finished just under two minutes ahead of me, but it was neigh impossible to keep up at that point.

It really was a wonderful experience crossing the finish line of a marathon. It was tough, although I think my first 100 mile bicycle ride years before was probably a tougher challenge. I was not nearly as exhausted as I thought I would be, although that should not underscore just how amazingly worn out I really was.

After the Finish

Still Alive!
Still Alive!

Immediately after crossing the finish line the organizers herd you into an area where you get a finisher photograph taken. After that you are brought inside the George R. Brown, given your finisher medal and then herded over to the medical area where you are weighed. They compare your weight after the race to what you weighed the previous day when you picked up your packet at the event expo. In my case, I was the same weight so they were concerned I might have hyponatremia.

They took me back into the medical area and had me fill out a questionnaire with the gist being how much water  you drank during the race and how you feel. In my case, I felt great (sore muscles aside) and I had been using an electrolyte add-in for my water during the event. In fact, towards the end I suspected I needed more fluids than I had drunk because I was covered in a thick layer of salt and I did not have to urinate at all during the event. After checking out my questionnaire and making sure I really felt okay they let me go, but this is an interesting data point for me and future runs.

After that little distraction, which unfortunately took a half hour, it was time to herd through the food area, get my finisher’s t-shirt and other goodies, pick up my checked baggage, change clothes and then find my friends. They of course were terribly worried about me since they were not sure when I crossed the finished line and then I was MIA for the extra half hour after I did.

Once everything was squared away we left, found ourselves an IHOP for lunch (mmm, pancakes and eggs!) and then went home. I treated myself to an ice bath as soon as I got home, which was more enjoyable than it sounds, followed by a wonderful shower and a slow, short bicycle ride in the park behind my neighborhood. Amazingly, I didn’t collapse into a coma as soon as I was done with all of that but stayed up until a normal time, even though I had been up since 3:30am.

One of the more amusing things to do after any endurance event like this is to add up just what all you ate during the day. In my case:

  1. Breakfast: banana protein cake
  2. Pre-run: 1 Gu packet
  3. During: 3 bags of Clif Shot Bloks, 2 bananas, 1 Gu packet, and 10 (!) cups of sports drink, plus about the same amount of water
  4. Post-race: 1 slice pound cake, 1/4 bagel, 1/2 cup scrambled eggs, 1/2 cup potatoes
  5. Lunch: 1/2 omelette and 1/2 harvest grain ‘n nut pancakes @ IHOP
  6. Snack: cottage cheese, granola, and raisins
  7. Dinner: banana protein cake

Wow! All of that sounds excessive but I likely did not really eat enough during the day as my heart rate monitor reported a energy expenditure of 3,878 kilo calories during the marathon itself. And let’s face it, you run a marathon and it is pretty much a license to eat whatever you can handle that day. I should have ordered a pizza!

The day after the marathon I found myself extremely sore, but not nearly as much as I thought I would be. I was slow, but fully functional. I did notice that as the day went on my entire back was highly sore, which is a new experience for me.

Today, two days after, I was less sore but my muscles were still screaming at me. It was time for a massage (which I stupidly scheduled in advance without thinking it was the exact time of the presidential inauguration, whoops!). Deep tissue massages are a bit sadomasochistic to begin with, but this one was truly an amazing amount of pain. The old cliché about muscles you didn’t know existing being sore was so true. Nevertheless, it is an amazing recovery tool and I found myself feeling wonderful afterward. The muscles in the middle of my back and my right shin were the most sore and the massage went a long way to relieving their pain.

I am supposed to take  break from all exercise until Thursday, at which point I can go for a short run or walk. This weekend the bicycling training season begins anew, and a gentle ~40 mile ride in the country will likely be a wonderful recovery tool as well.

The Training

I started running in late April, 2008 after the MS150 bike ride between Houston and Austin. My cardiovascular conditioning after the bicycle training season was excellent, which made pushing myself during the runs easy, but my running technique itself was not sound. My good friend Teri noticed how I was running and offered a few suggestions which dramatically changed how I ran and the impact it had on my body. After that point, running became relatively easy.

I signed up with Fort Bend Fit to utilize their training program for the 2009 Houston half-marathon. My training progressed much faster than I expected and I ran my first half-marathon in Albuquerque in October, followed by the warm-up Houston half-marathon a week later. At that point, I decided to switch to the full marathon race and continued to follow the full marathon training program.

During the training season I ran 600.5 miles over 120 hours and 56 minutes, expending a whopping 75,711 kilo calories – not including any of the cross-training I did. The Fort Bend Fit training program was a full 28 weeks long, making it possible for anyone to go from being able to do a 5K distance to a full marathon during that time.

During the training season I ran 2 5K races, a 5 mile race, 2 half-marathons, a 25K race and a 30K race, not to mention all of the nurmous additional training runs in between.

It was a truely awesome experience.

Now What?

The day of the marathon, and the following Monday, I had zero interest in ever running another marathon. Zero. I like bicycling a whole lot more, and that experience is a whole lot easier on your body (unless you crash). But today I noticed I am already looking for future events and reading different recovery scenarios for the first time marathoner. D’oh. Maybe I should just give in and start doing triathlons. An ironman would be fun…

Marathon Training : Week 20

It is hard to believe but week # 20 of marathon training has come and gone. We capped the week with our longest run yet of the season at 16 miles. It was a great run, and one of my fastest long runs of the season with a 9:44 minute/mile average pace. It was also the coldest weather so far this year, with temperatures in the upper 40s throughout the run. 

For the remainder of the season we only have two longer runs before the Houston marathon: a 30K in December and then a 21 miler a few weeks later.  I did decide after the 25K a couple of weeks ago to transfer from the half to the full marathon, so I’m fully dedicated to that goal now.

2008 Duke City Marathon

Today I ran the half-marathon course of the 2008 Duke City Marathon event in Albuquerque, New Mexico. This was my first organized half event and I wasn’t entirely sure what to expect. I followed the advice of my running group back home and treated it just like a training run.

Luckily, it was a very well organized event. The “motivation stations” every 2 miles had plenty of water and gatoraide so I wound up not using my water belt much during the race.

The route had us wind through downtown for about two miles before taking us onto a trail system that followed the banks of the Rio Grande. This had the double benefit of being the lowest altitude in the area and fairly flat.

I was concerned about the high altitude compared to the near sea level back home, but it turned out to be a non-issue. My heart rate during the race was the same as home and I never felt light-headed or got a headache afterwards. I completely credit this to my hike up the mountain 2 days before and the pint of beer I had at the top.

I finished the race in 2:09:35 which is about a 9:54 minute/mile average pace. That is just a tad faster than the pace I average during my long training runs so I am really pleased with that result.

Woo hoo; now to try and improve my time at next week’s Houston half.

halfway 2

Marathon Training – Week 11

Week 11 was capped off with a 12 mile run this morning at Sugar Land Memorial Park. My pace group’s run had has go north out of the park along University Blvd, turning into the University of Houston @ Sugar Land campus and running around the parking lot twice, and then returning to the park via University again. From there we turned east onto Commonwealth Blvd and followed that all the way to Oilfield Rd before turning once again to the park. Once back at the park we then ran both loops of the park to finish.

It was a really good run. I finished in 2:06:30 which puts me right at the pace I’m trying to maintain. I listened to my friend who told me to eat a bigger breakfast before these longer runs, and that helped maintain my energy level throughout out the run (supplemented with 2 Gu packs during the run as well). I didn’t bonk at all during the run, and maintained a pretty consistent pace. Perhaps the only drawback was learning new things that became sore: my arms and right shoulder especially are screaming at me right now.

The rest of the week’s training was uneventful except for the fact that we were impacted by Hurricane Ike all week. Last Saturday’s run was cancelled so it has been two weeks since I last ran a long distance. I was able to get in all the required training this week, despite the storm recovery, and fortunately our running group took the effort to plan out a route that was mostly free of storm debris.

In week 12 we ratchet the mileage back down to a 10 mile long run; the Houston Half Marathon is about a month away so I have full confidence in running that, since I effectively was only a mile away from that today.