Playing with the Activity Monitor on the Garmin 920

The Garmin 920 is designed to be used not only to record activities using GPS, but also as an all-around activity monitor. When I purchased mine, I wasn't planning on using it that way, but when my normal everyday watch broke, I began wearing the 920 around all day.

I began to notice the number of "steps" I took each day, and I actually liked when it told me to "move" after an hour of inactivity. There are still some kinks to work out, like when it told me to "move" while I was riding my bike at 20 miles per hour, with the GPS engaged.

I started to wonder if the 920 could give me a more accurate count of the number of calories I burned each day than my usual method of entering all my exercises into MyFitnessPal.

So for the last couple of weeks, I decided to compare the calories tracked by my Garmin and MyFitnessPal. 

This very complicated graph gives you the results:

The light blue and the yellow lines give you the raw data from MyFitnessPal (MFP) and Garmin. As you can see, there are some wide discrepancies. On March 15 MFP counted 1680 calories versus 3726 for Garmin. There are also a few days when the Garmin count was significantly lower than MFP.

I noticed that the days when Garmin was way lower than MFP were days when I did activities that the Garmin doesn't capture, such as the elliptical trainer and strength training. So I made an "Adjusted Garmin" count (in brown) that took care of most of that -- but the two numbers were still off by quite a bit.

Then I noticed that the days when Garmin was way higher corresponded to long rides. Clearly Garmin is giving me way too much credit for my calorie burns on rides because I was basing my eating off the MFP numbers those days and I didn't notice feeling exceptionally hungry and I certainly wasn't losing tons of weight. So I created a "double-adjusted" Garmin count (in red on the graph) that ignores about 40 percent of the calories burned cycling. As you can see, the red count is much closer to the light blue MFP count.

But Garmin was still giving me credit for about 30% more calories than MFP, and MFP wasn't giving me any credit for days when I took a lot of steps (like when I was timing a race). So I created an adjusted MFP count to account for that. This one is just 18% different from the Adjusted Garmin count, and there's less day-to-day variance as well.

So it seems I could get a decent count using the activity monitor on my Garmin if I could get it to track the few additional activities like the elliptical trainer. Since Garmin consistently overestimates calories, I would have to factor that in, but in the end I could have a totally-automated system for tracking calorie burns.

Another option would be to get a separate activity monitor that also tracks heart rate. Since heart rate tracking can give more accurate calorie counts, this would solve two problems at once. Anyone want to get me one of these babies as a gift?

Turning the corner on my injury

The last time I ran more than 4 miles was nearly a month ago, on February 7. Although I have shared the news with my friends and on social media, I haven't written about it here. Maybe if I don't write about it it isn't real?

But it is real, and of course it's my own fault. The following paragraph is probably best skipped, but it explains how I got to where I am now. I first noticed my sore hamstrings sometime last fall. The pain started on the left leg and gradually migrated rightward and upward. Back in October, I was racing all-out in an effort to qualify for the first corral at Bloomsday in May. I raced a 5k every week, and after the first couple of races, my hammies were so sore that I couldn't do any speed work midweek. I backed of the speed work first, then backed off the racing (good moves), then decided I should be doing regular squats instead of front squats during strength training to better target my hams/glutes (perhaps a good move, but done too rapidly). I backed way off on the squats, then tried gradually ramping the speed work, and felt okay but not great -- I could still feel some of the same issues in the hamstrings.

That got me to February 7 and the Uwharrie 8 mile trail race. I had signed up for the race on a bit of a whim: Entry is via lottery and I figured I wouldn't get in to the race so what was the harm in trying? Of course I got in, so I had to do the race. For a better description of the actual event, see Chas's post on the 20-mile race here. My race, for all practical purposes, ended at Mile 2.5

I started the race okay, hitting the uphill start hard. But when the trail leveled out, I felt I should be giving a similar effort and staying with the other runners. Bad move. I need to remind myself early and often that I'm not a good downhill trail runner, probably due to a deadly combination of age and klutziness. I fell once and felt a tweak in my right glute, but nothing to stop me from running. Then, about 2.5 miles in, I stumbled hard and onto some jagged rocks. As I crashed to the ground on my left knee, I felt my right glute tighten.

There was a bloody gash on the left leg, but the real injury was on my right leg. Here's what my left leg looked like when I got home:

Yikes!

In almost certainly a boneheaded move, I decided to limp on ahead rather than turning around and walking to the road at Mile 2. There were spectators there who could certainly have given me a ride back to my car, but I chose to continue, getting passed by what felt like dozens of runners every mile. Eventually I picked my pace up to a slow jog, but every time I tried to run faster than around a 9-minute pace, my right glute told me to slow down. Amazingly, I did not finish in last place! I was actually 88th out of 197 finishers, averaging a 12:50 pace for the race.

Two days later I decided to try a slow recovery run, but I was unable to go even 100 meters. I took a week off of running and made 1/10 of a mile the next time I tried. I could walk and bike without difficulty, but running was impossible. I was gaining weight because I wasn't putting in anywhere close to the equivalent workout I could do running. I decided to try swimming and took out a membership at the Y so I could use their pool. I could swim, too, but I still was gaining weight and didn't seem to be making any progress running.

Even the cycling seemed to be cursed: I went on a planned 20-mile mountain bike ride in Columbia, SC (to escape icy conditions closer to home) and my chain broke after 6 miles.

I'm now in the middle of 3 weeks of travel to wintery climates, so I haven't had many more chances to ride outside. I've been hitting up elliptical machines in gyms from Spokane to Virginia to Minnesota.

I also did something I never thought I would do: I went to a chiropractor. This actually seemed to help a little bit (or maybe it was just the time off of running). I tried running in Spokane and made it a half mile. The next day I went a mile. I could do it, limping along, with a tolerable bit of pain in my right glute / hamstring. The pain wasn't getting better, but it wasn't getting worse. I could barely run 10-minute miles on flat terrain.

After a couple days home and more chiropractor visits, I ran two miles, with similar pain levels.

Then this morning, back on the road in Northfield, Minnesota, I had a bit of a breakthrough. My run actually wasn't as painful. I ran 1.5 miles to a gym, did my usual bit of strength training plus 15 minutes on the elliptical trainer, then headed back to my hotel. I was feeling even better now that I'd warmed up and decided to go for my first post-recovery 5K. I finished in 29:26 (not counting the 70 minutes I spent at the gym). That's actually not a terrible 5K time - it's a 9:29 pace. Well, it's pretty terrible for someone who not long ago was kicking himself for not breaking 19:00 in a race, but it's semi-respectable for a recreational runner.

I might honestly be on the road to recovery now. I want to make this one stick, so I'm even going to do something else I've never done before: Adopt a mantra. My mantra will be the following:

You only want to make one comeback

In other words, I don't want to rush it; I want to take my time and do this right, so I don't have to do it all over again, only slower. This time I'm going to stretch, roll, and massage, even when it doesn't seem like I need to. I'm going listen to my body during runs and make sure to stop running before it hurts. I'm going to supplement my running with sensible strength training and cross-training, again, not doing anything to hurt myself. I'm dropping out of my next two planned races, and I'll be prepared to drop out of more races if I'm not confident I can do them without re-injury.

But I will come back, and I'll be every bit of the runner I was before. I love running too much to stop. If that means slowing down, that's fine, but I'm not ever going to stop.