Save a life, wear a Garmin

Adventures with heart zone training

Back when I was an avid triathlete, and actually, to this day, I rely on a Garmin watch to monitor a variety of metrics. It tracks how far and how fast I swim, bike and run. It also tracks my heart rate with reasonable accuracy. For even better accuracy, I’ll wear a chest strap while biking or running. For the most part, I collect all of these metrics on swims, bikes, and runs, and rarely look back at the data.

During a race, it is extremely useful. It allows me to monitor my heart zone so I do not start off too strong, which is always a big temptation.

I think the theory behind heart zone training is that you can strengthen your heart just like you train any other muscle, and if you train your heart to pump more blood at a higher throughput for longer amounts of time, that will directly translate into better performance. For me, I think it worked, but perhaps a little too well. When I started training, my resting heart rate was fairly typical, in the high 60s. By the time I was heavy into endurance work, I had dropped my resting heart rate down into the 40s and was racing faster.

I should note that I am not and was never an elite age group athlete. I would typically finish in the top half of my age group, except for the one shining exception of the single full Ironman race I ran, I never reached the podium. An Ironman race involves a 2.4 mile swim, a 112 mile bike ride, and then a full 26.2 mile marathon. I spent six months training for the race with a heart zone coach. The training is basically a full time job, taking 30 or more hours a week.

After my Ironman triumph, I kept improving over the next two seasons. I got to the point where I could run a half Ironman race a little over five hours, not fast for an elite athlete but pretty fast for me. I set my sights on breaking that five hour threshold at the Patriot Half-Ironman, and upped my training even more.

About a month before the Patriot race, I was out for a light recovery run and noticed my Garmin watch was telling me my heart rate was essentially at full race pace. This was odd - I didn’t feel like I was exerting myself; I assumed the watch was glitching on me. This went on for a few more days, where doing very light exercise, my watch was reporting heart rates in the 130s or higher. I also noticed my resting heart rate wasn’t going down to its usual rate.

I decided I’d confirm my glitchy watch theory at the gym. I started walking on a treadmill, and to my great surprise, my heart rate shot up to what it is at the end of a race - well into the 150s. Uh oh. Unfortunately the watch wasn’t the issue. I had no idea what my heart was doing. I felt fine, but my heart rate was crazy.

So I called up my trusty medical consultant - my father-in-law - who suggested I get an EKG at an urgent care facility. I headed over to the closest one I could find, and told the intake person that I needed an EKG. She was extremely skeptical. I’m sure they get a lot of people with self-diagnosed problems that just waste their time. She took her own measurement confirming a “normal” pulse reading around 70 beats per minute, and at that point attempted to see me on my way. She looked at me with exasperation, assuring me that I had a very normal pulse, and had nothing to worry about.

I insisted on getting the EKG; and she sighed and relented. She hooked up the various sensors, performed the test, and went to get the readout in a separate room. When she came back, her bored expression had transformed into one of high alarm. Apparently, my atrial chambers were beating at not 70 beats a minute but 300! This is a dangerous condition, especially since it had been going on for over a week. I was at risk of throwing a clot straight to my brain when my heart returned to a normal rhythm, because blood had most likely been pooling in those chambers.

At this point I was pretty amused, not really understanding the gravity of the situation. I was just happy to have been right. See - I told you something was going on with my heart! (I admit it - one of the things I most enjoy in life is being right.) The nurse was dumbfounded. She insisted she call an ambulance for me. I needed to be hospitalized immediately. She made me sign a waiver taking responsibility for driving myself to a nearby hospital and informed me she would call ahead and alert them.

When I got to the hospital, it was all hands on deck for the cardiac team. I was immediately whisked into a room and attended to by a bunch of people. I think they thought I was having a heart attack. They couldn’t understand why I wasn’t exhibiting any symptoms. After some more tests to make sure that wasn’t the case, and checks to make sure I didn’t have any clots, they eventually performed a cardioversion; essentially they hook you up to a car battery and shock your heart back into a normal rhythm.

That was the beginning of the end of my endurance race days. I had essentially trained myself into a heart condition. I never did break the five hour mark - I had to drop out of both of my half-iron races that summer. I started training again, but my heart didn’t stay in a normal rhythm for long. So eventually I had to have a super cool surgery to scar the inside of the heart to prevent the electrical impulses from going haywire - that surgery is a story for another day.

For me, once I went through all that, I just never felt comfortable stressing my heart, which made the Mass General cardiac people very happy, since they consider endurance athletes to be a special kind of crazy.

So that’s my story of how my Garmin watch saved my life. I remain a very loyal Garmin customer.