In a first blog post on pacing apps for smartwatches, we take a closer look at what pacing is and why it is one of the most important tools for dealing with symptoms such as fatigue and post-exertional malaise (PEM).
We also introduce the Mindful Pacer app, which is currently being developed at the University of Zurich for people affected by Long COVID. In addition to Mindful Pacer, there are several other applications that can support pacing through heart rate monitoring and activity/energy diary functions. In this second part, we will present some examples.
The pacing watch for Fitbit
The pacing watch app was developed by Marco G., who has Long COVID himself. The app supports people with Long COVID and ME/CFS in self-monitoring their heart rate and stress levels.
The idea for the app came from Marco's own experiences trying to use an activity diary and heart rate monitoring for pacing. The pacing watch is based on the Altea guidebook to heart rate monitoring, which is based on an "Ultimate Guide for Pacing" from an ME/CFS self-help group and the recommendations "Pacing with a heart monitor" from an ME/CFS Facebook group.
The heart rates measured every minute are assigned to a pulse zone according to these recommendations, which enables visualization throughout the course of the day. The heart rate zones are based on empirical values and are intended to help avoid activities that require the transition to anaerobic metabolism.
At low levels of exertion, our body is in aerobic metabolism, in which cells utilize oxygen to produce energy. Anaerobic metabolism occurs during strenuous exercise.
In healthy people, the transition from aerobic to anaerobic metabolism is reached at a heart rate of approximately 85% of the maximum heart rate. It is hypothesized that this threshold is significantly lower in people with ME/CFS, at around 55% of maximum heart rate.
According to this theory, transitions to anaerobic metabolism lead to crashes in ME/CFS patients and must therefore be avoided at all costs. What is important here is how often and for how long (cumulatively) the limit value is exceeded per day.
The pacing watch app is designed to help visualize the course of the heart rate throughout the day in order to be able to recognize when the heart rate zone is too high. This helps to identify and avoid the causes of crashes.
The app is only available for Fitbit watches and includes the following functions:
- Heart rate monitoring: the app continuously records the user's heart rate throughout the day and assigns a specific heart rate zone every minute. The zones are marked with different colors to allow a clear visualization of the current status.
- Zone classification: There are 9 different zones, each zone refers to a specific heart rate range. The zones are indicated as a percentage of the maximum heart rate (zone 1 = <33% to zone 9 = <90%). The maximum heart rate is calculated as 220 minus the user's age.
- Statistical representations: Users can see the distribution of their heart rate zones throughout the day in a bar graph.
- Haptic feedback: The app can send vibration signals when a new heart rate zone is reached.
- Weekly statistics (only available for Versa 3 and Sense models): After taking off the watch, weekly statistics are displayed, providing an overview of the heart rate data from the last week.
The pacing watch app is available in the Fitbit mobile app, download here.
Screenshots of the pacing watch app for Fitbit.
International offers
Overall, there are currently only a few applications available that support people suffering from PEM or fatigue in pacing. The ME/CFS Pacing app, for example, offers an energy tracker that has been specifically developed for people with ME/CFS. Other examples are the Bearable app or the Chronic Insights app. However, the latter was developed for people suffering from chronic pain rather than people suffering from fatigue or PEM. Most offerings focus on a smartphone application and do not offer a link to smartwatches for heart rate monitoring.
The visible app
The visible app was developed in the USA by a young Long COVID patient with the aim of “making invisible diseases such as Long COVID and ME/CFS visible”.
Similar to the MindfulPacer, the system combines an app with a diary function for documenting energy levels and activities with an application that measures heart rate. However, visible relies on a heart rate tracker produced solely for this purpose instead of integration with well-known smartwatches or fitness trackers.
While the smartphone app including the symptom diary is freely available and free of charge, a visible plus membership ($19.99 per month) is required to connect to the heart rate tracker. This offer is currently only available in the USA and the UK.
Screenshots of the visible app.
Integrating pacing into your everyday life is difficult and requires a lot of self-discipline, attention, and a deep understanding of which activities are particularly energy-sapping. A pacing app in combination with heart rate monitoring can provide considerable support in finding and maintaining your own energy limits.
In our forum, some people have already shared their experiences with the pacing watch application for Fitbit. We hope that the further development of these offers will soon be able to provide support for as many Long COVID and ME/CFS patients as possible.
