FatigueSense app

[Utsikt]

We actually agree that long-term tracking of activity, symptoms, sleep, and perceived wellbeing is valuable. In fact, we’ve conducted a study with people experiencing long COVID over a three-month period, analyzing activity and fatigue patterns. That work is currently under peer review in the journal to be published, and we plan to expand to gain further insights into long-term effects.

Three months is not long term, it’s very much short term. One year is the bare minimum if you want to have any hope of getting data across fluctuations.

Regarding what the app is or isn’t, it really does not matter what you technically say it is. Nobody here has claimed it’s a medical advice according to the law.

It’s presented as, and more importantly, will be interpreted as, a tool that will provide the used with better insights about how to manage their day to day. It’s presented as being based on research, not as a tool for research.

It is also presented as developed by «digital health experts». The only reason to tell users that is to imply that it is endorsed by health experts.

And the website literally says it’s going to provide guidance:

It combines wearable signals, health trends, and AI analysis to deliver practical guidance people can actually use.

So there is some dissonance between what you say here, what the website says, and what the screenshots tell us..

Spoiler: From the website

Your Day at a Glance​

The Dashboard gives you an instant overview of your fatigue and energy levels. See your AI-predicted scores, daily briefing with personalised recommendations, and data quality indicators all in one place.

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  AI-predicted fatigue and energy scores updated daily
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  Personalised daily briefing with actionable recommendations
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  Quick actions for Activity Pacing and AI Insights
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  Morning assessment and end-of-day check-in prompts
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  Data quality monitoring alerts you to wearable sync issues

Know Tomorrow's Fatigue Today​

FS AI is the heart of FatigueSense. It analyses your wearable data to predict your fatigue outlook whether that's today's forecast or tomorrow's. The prediction adapts to time of day and gets more accurate as it learns your patterns.

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  Time-of-day aware: morning shows today's outlook, evening shows tomorrow's forecast
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  Top 3 drivers explain what's influencing your prediction in plain English
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  Personalised recommendations written in a supportive, non-clinical tone
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  Intraday check-in lets you agree or disagree with your predictioins
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  Personal model indicator shows when your custom prediction model is active

Your Personalised Activity Budget​

Get a daily activity budget tailored to your predicted fatigue level. FatigueSense tells you how many steps and active minutes you can safely do, broken into morning, afternoon, and evening blocks with built-in rest periods.

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  Personalised step and active minute targets based on your fatigue level
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  Time-blocked schedule: morning, afternoon, and evening with mandatory rest periods
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  Live progress tracking against your daily budget
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  Activity Planning tool to check if planned activities fit your capacity
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  Pacing history: see how past pacing choices affected next-day fatigue

Discover What Drives Your Fatigue​

AI Insights analyses your history to find patterns you might not notice. It identifies your personal fatigue triggers, ranks them by confidence, and shows you exactly what's behind your good and bad days.

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  Personal trigger identification (e.g., "Poor sleep → high fatigue next day")
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  Confidence levels and evidence counts for each trigger
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  Triggers update as more data is collected
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  tVNS correlation analysis for research participants
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  Understand the drivers behind your energy patterns

What-If Activity Simulator​

Curious how changing your sleep or activity would affect tomorrow's fatigue? The Activity Simulator lets you adjust variables like sleep duration, steps, and active minutes to preview the predicted impact before you commit.

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  Adjust sleep, steps, and active minutes with intuitive sliders
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  See a live preview of predicted fatigue based on your changes
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  Plan your activities with confidence — know the trade-offs in advance
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  Powered by your personal AI model for accurate, tailored results
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  Great for planning big days, recovery days, or pacing experiments

A Profile Built Around YOU​

FatigueSense doesn't use population averages — it builds a personal profile specific to your body. Over time, it learns your baseline HRV, typical sleep patterns, normal step counts, and what deviations from YOUR normal mean for YOUR fatigue.

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  Personal baselines for HRV, sleep, steps, and heart rate
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  Maturity indicator: Building → Emerging → Established → Robust
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  Deviation analysis: see how today compares to YOUR normal
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  Confidence score showing overall profile reliability
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  Profile refreshes automatically as new data arrives

Two Minutes That Make the AI Smarter​

A quick morning check-in and optional evening reflection. Rate your fatigue and energy on a smooth 0-100 scale, note any contributing factors, and help the AI calibrate its predictions to your experience.

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  Visual Analogue Scale (VAS) sliders — scientifically validated measurement
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  Real-time colour feedback from green (good) to red (severe)
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  End-of-day check-in closes the feedback loop for the personal profiling agent
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  Free-text fields for contributing factors

 

[Trish]

One thing I find confusing is the use of heart rate variability. It is said that HRV is anindicator of 'autonomic function' as if low variability is a sign of autonomic malfunction. It is also said to be low with deconditioning and higher with fitness. But presumably in the context of predicting tomorrow's fatigue it has nothing to do with these but is a measure of how often there was a bout of activity that put the heart rate up? Is this really usefully called 'HRV' rather than just a measure of tachycardia. I may be missing something here.

An Overview of Heart Rate Variability Metrics and Norms​

Fred Shaffer 1,*, J P Ginsberg 2

PMCID: PMC5624990 PMID: 29034226

Heart rate is the number of heartbeats per minute. Heart rate variability (HRV) is the fluctuation in the time intervals between adjacent heartbeats (1). HRV indexes neurocardiac function and is generated by heart-brain interactions and dynamic non-linear autonomic nervous system (ANS) processes.