Shower is one of those places where I get a break from everyday’s life distractions and from the digital world as well. Putting my head under a hot stream of water kind of makes it work, and ideas, sometimes crazy, emerge afterwards.
After today’s thoughts I recorded a video – after taking my shower and dressing up, as a friend kindly pointed out, so here it is! It covers my thoughts, i.e. health data usage from fitness trackers, data portability, its use in a medical context, protecting the data etc.
One thing I mentioned during the video is that I requested an export of all my personal data. This post will be very briefly covering what I got, in high level only.

After about 30 minutes, I was able to download a ZIP file that contains ALL my potential Garmin data across all their products as seen in the screenshot below.

I dived down into the DI_CONNECT folder to find Garmin Connect data, and have found the following options.

Curious, I opened the Connect Fitness folder, which contains several JSON files about activities, tied images, etc. Using the Atom editor on MacOS and the Pretty JSON module, I checked the content of one of the files:

Looking further in the directory, two important folders are called DI-Connect-User (it provides all sorts of metrics on wellness (stress level, estimated calories, average heart rate, etc.) – those being contained in a file with the following name format: UDSFile_2020-10-14_2021-01-22.json
I am not an expert but I wasn’t able to find full heart rate data in this JSON file, so perhaps it is stored elsewhere, or each entry may relate to a given timestamp (sampling interval?)
The next folder with interesting data is called DI-Connect-Wellness and contains sleep data:

Most of these JSON files seem to show only aggregate data. There is a folder called Uploaded files which contains a big zip file. When unzipping it, many .fit files are in the folder (in my case, 3241 files so far, considering I have the VivoSport 4 device for approx 8 months). Those files contain raw data and are probably where all the metrics are stored in detail.
From a portability perspective, someone would have to probably decode the data in those .fit files to be able to get full usable data.
But it might not be necessary at all, a health analysis company / provider could very well work together with Garmin to access this data through REST APIs, and the customer (the Garmin user) could grant/revoke permissions as needed.
And of course, a similar course of action could work with any other smart watch / fitness equipment manufacturer, so maybe standards are not even required.
Max’s Opinion
I’m curious about the possibilities here. Health is THE paramount personal and sensitive topic for us all, but knowing (and preventing) issues way ahead is something that most of us would like. The major challenge resides in my view not so much on obtaining data, but more on the competency of the companies who will then subsequently analyze it.
If there’s one thing the Theranos scandal has though us, it’s that we can never be cautious enough when it comes to health.