The Apple Watch and other smartwatches record a humoungus amount of data about what you do every day. This post will show you one of the visualizations you can build for that data: how to build a heatmap of your walks or ride.
This is what the final product looks like (truncated view to preserve privacy):
How to get the data
I downloaded the data from my iPhone by going to the health app and clicking on
my profile and then clicking on “Export All Health Data”. I unpacked the zip
archive and it gave me both files and folders. One of the folder is called
workout-routes, it contains all the gpx (format to store gps route) traces for
Building the heatmap
I decided to use https://github.com/remisalmon/Strava-local-heatmap. Calling it with the following arguments (I researched the bounding box for San Francisco where I live):
python3 strava_local_heatmap.py \ --gpx-filter '*2019*' \ --gpx-dir ~/Downloads/HEALTHDATA/apple_health_export/workout-routes \ --zoom 15 \ --gpx-bound 37.6040 37.8324 -123.0137 -122.3549
It failed to complete for two reasons: (1) my python3 distribution wasn’t built with
tkinter, and (2) it claimed that no data was present. (1) was trivial to fix as
you can see below. For (2) I did a bit of debugging and realized that
strava_local_heatmap.py parses xml using regexp instead of
using a regular XML parser. It made assumption about the order of the fields that
didn’t match the way that Apple serializes the data. I fixed both
of those issues and tried again:
From 12eb2b1bbccf64707891f5bda5ee139bfbe0677e Mon Sep 17 00:00:00 2001 From: xxxx Date: Sat, 14 Mar 2020 12:54:26 -0700 Subject: [PATCH] Make it work on Mac OS with apple watch data --- strava_local_heatmap.py | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/strava_local_heatmap.py b/strava_local_heatmap.py index 9fd4e70..8388869 100644 --- a/strava_local_heatmap.py +++ b/strava_local_heatmap.py @@ -28,6 +28,8 @@ import urllib.error import urllib.request import numpy as np +import matplotlib +matplotlib.use('agg') import matplotlib.pyplot as plt # parameters @@ -145,7 +147,7 @@ def main(args): if '<trkpt' in line: # trackpoint latitude, longitude tmp = re.findall('-?[0-9]*[.]?[0-9]+', line) - lat_lon_data.append([float(tmp), float(tmp)]) + lat_lon_data.append([float(tmp), float(tmp)]) else: break -- 2.25.0
I didn’t contribute this change back to Strava local heatmap as the readme indicates that an explicit goal of the project is not to do real XML parsing. That is a questionable decision is you ask me.
I tried all the following exploration with my health data:
- Join heart monitoring data with calendar data to identify what meetings are stressing you out the most!
- Identify the activities that are the most worth it for burning calories (effort == calories per minute). This is the result for mine, as expected stair climbing is worth it!
- Identify long term trends in heart rate or any other metrics