Comparing step count and exercise intensity in driving cardiovascular fitness (Apple Watch data)

[Blog post author here, AMA]

Many fitness trackers recommend a default of 10,000 steps per day. But what does the data say?

We analyzed 458,000,000 distinct data points from an Apple Watch app, Cardiogram, which stores both heart rate and step count. Using resting heart rate as a proxy for overall level of fitness, we compared the effects of various step counts and exercise intensities.

The data and analysis is here: http://blog.cardiogr.am/2016/02/12/do-you-really-need-10000-steps-a-day-2/

I'm happy to answer questions. I'm also curious to hear what you'd like to see in a follow-up analysis—there are all sorts of questions you can answer with this type of data!