I'll never forget the first time I wore my iPod in an armband on my run along the Pacific. I was in college, and getting into the zone meant, for the first time, doing it with my own music. But the armband weighed down my left side and gave me an unfortunate tan line (making the iPod mini a welcome upgrade a few months later).
It was an early foray into wearable gadgets, before gadgets themselves became wearable. Now, smartwatches such as Pebble interact with your smartphone's apps, while activity trackers such as Fitbit and Fuelband track movement, steps and sleep. But none of them quantify where my passion lies — running.
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That changed when I discovered the Mio Alpha, a wristwatch that tracks heart rate. Among other benefits, targeting a heart rate zone can build speed (90-100%) or burn fat (70-80%). Heart rate-tracking chest straps are nothing new (and run around $40), but seem a hassle for my 20-minute morning jog.
I soon discovered the Alpha is not alone in its category. In addition to with Mio's tracker, I experimented with two more heart rate monitoring activity trackers — Basis and Sync Burn — to find the pros and cons of each.
There is no official Mio app at this time of writing, but the Alpha pairs with smartphone apps Runkeeper, Endomondo and MapMyFitness, to name a few. This means I can continue using my running app of choice — Runkeeper — and the Alpha seamlessly sends both heart rate and heart rate zone as audio cues, along with the existing distance and speed cues in Runkeeper.

Runkeeper data from a recent run, err, jog.
Unlike an activity tracker, the Alpha is meant to be used for the duration of your fitness activity — not all day. This means you must turn off heart rate tracking once you're done working out so the battery doesn't drain. However, you can continue to use the watch even if the heart rate feature is turned off (battery life with the heart rate monitor left on lasts a couple of days).

The Mio Alpha fits onto the wrist more like a band than a watch and was the most comfortable of the three.
The watch is waterproof, but that doesn't mean it works for swimmers — the motion of water throws off the monitor. Heart rate data is accurate for running up to 14 miles per hour.
If you'd like to know your resting heart rate, as a measure of fitness, you could sleep with the Alpha on and check right when you wake up in the morning.
Mio's audio cues via Runkeeper are the game-changer for me. I wear my headphones running anyway because I'm listening to music, and hearing my heart rate rather than looking down at my wrist is less distracting.
You can purchase the Alpha on Mio's website for $199.
You'll never have to charge the Sync Burn, and at $129 it's one of the more affordable wrist-worn heart rate trackers available.
The Burn works with MapMyRun (and other MapMy apps). MapMyRun is free, but an MVP membership (which costs $30 per year) is required to view your heart rate log. So, to benefit from the heart rate capabilities, consider the price tag as $159.
Much like Runkeeper, MapMyRun will provide audio cues on heart rate, but you have to press a button on Burn to check your heart rate, which I found distracting. The app does not log the data for you to check later.

In Sync's line of activity trackers, the Burn measures heart rate and is the best fit for runners.
Although you don't need to recharge the Burn, the battery is expected to run out after one year.
You can purchase the Burn at various sporting goods stores or on Amazon (the price at this time of writing is $61 on Amazon). The device is compatible with iPhone 4S and newer.
The Basis is the best choice for runners interested in utilizing heart rate training, but who also want to explore activity tracking such as sleep patterns, step counting and skin temperature.
The Basis has its own app, and while I'm usually skeptical of a device that does not integrate with other services, the features in the Basis dashboard are solid. It suggests goals such as a morning run — which is supposed to help you sleep better (sign me up!). Since Basis tracks activity and sleep, it provides good feedback on how daily activities might affect each other.

The small buttons on the four corners of the watch face are touch-sensitive for easy access to data during the day.
I'm a bit addicted to the mapping provided by running apps, so it's unfortunate that Basis does not sync with any of them. That said, Basis does a good job of making your data digestible. You'll know you ran for, say, 34 minutes, and the dashboard shows how your heart rate increased or dropped during the activity, along with skin temperature, perspiration and steps (but unfortunately, not distance). During the run, you can check heart rate by tapping the band, but you'll have to mentally keep track of which zone you're in.

I wore the Basis for a full week, and this was a typical day at work.
If worn continuously, Basis will need to be charged once or twice a week.
Basis has two versions, the B1 for $179 (which I tested) and the Carbon Steel, $199, both available on the company's website. Colorful watch bands are sold separately, and perhaps not a bad investment (when I was home for Christmas, my dad commented, "I was surprised to see you wearing something so masculine"). Basis has an iOS and Android app, as well as a web app and desktop apps to view your data.
My dream fitness tracker would measure heart rate, but also log distance and routes — thus allowing me to leave my phone at home. My iPhone is lighter than my first iPod a few years back, and workout pants designed with a smartphone-sized pocket are the norm these days. But the fewer things I carry when I run, the less encumbered I am, and the more I'm able to race ahead without a care.
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