By adding a heart rate monitor, speed sensor, and cadence sensor to the already revolutionary functionality of its newest Edge head unit, Garmin's Edge 520 Bike Computer Bundle comes ready to take advantage of metrics, measurements, and features that aren't supported by any other Garmin Edge model. The direct connectivity with Strava is even more exclusive: the Edge 520 is the first head unit in the industry to interface directly with Strava segments.
We like the 510's ability to auto-sync with Garmin Connect segments, but let's face it: when it comes to competing for segments, Strava's the real battle ground. The 520's direct connection to Strava gives you an edge in that battle because the segments update live as you ride, simultaneously displaying the stats of your present performance against the current K/QOM and your own personal record in order to help you more effectively portion your efforts. In addition to just being a lot of fun, live Strava connectivity also provides more structure to training and race-prep by keeping you constantly linked to an external referent, allowing for data-parsing and adjustments during the rides themselves, not just in between them.
The list of parse-able, power-related metrics has also expanded compared to the 510, so the data nerds get as much of a win as the Strava junkies. For us, the big star here is that, when paired with Garmin's Vector or Vector 2 power meter pedals, the 520 calculates your functional threshold power (FTP). Once equipped with an FTP, you'll be able to calculate ideally timed and measured efforts for intervals tailored to your own fitness level. Instead of burning out trying to hit arbitrary output numbers, knowing your FTP helps you stay at a level that's more effective for increasing your present level of fitness. After all, the real point of intervals isn't punishment; it's improving. The Edge 520/Vector combo makes that improvement even more efficient.
When it's paired with any other ANT+-compatible power meter and the included heart rate monitor, the Edge 520 still provides VO2 max estimates and recovery time guides. While the former is obviously useful in planning and executing a training regimen, the latter helps to maintain focus on an often neglected part of training: the apparently negative space between workouts. Maximizing recovery is almost as important as maximizing the efficiency of your time in the saddle; however, until recently, virtually all of the training apps and devices also ignored this period, focusing exclusively on the activity portion of training. This feature is just one more way the Edge 520 keeps you focused on improving your form, even if that improvement involves low-key recovery.
In addition to the above new shininess, the Edge 520 Bundle also supports all of the 510's functions. It's compatible with Shimano's D-Fly Data Management system, effectively replacing the PRO Scio ANT+ head unit, and also works with ANT+ turbo trainers. It performs all the basic computer functions speed, trip time, trip distance, odometer and the GPS and GLONASS compatibility keeps you located no matter where your ride takes you. It automatically uploads to Garmin Connect, syncs with smart phones for notifications, and displays weather information so you're never out of the loop or surprised by changing conditions mid-ride.