Guides on fasting with live biometrics - reading your Garmin data, understanding HRV, breaking a fast well, and choosing the right app. Practical, evidence-aware, and never pushing extremes.
Your watch already tracks the story of your fast - heart rate, HRV, Body Battery and stress. Here's how to read it, hour by hour.
Heart rate variability is the best single signal of how your fast is really going - if you know how to read it against your own baseline.
Breaking a fast well is the moment that matters most - and the right approach depends entirely on how long you fasted.
Most fasting apps are just a countdown timer with a subscription. Here's the one capability that actually separates them - and how to evaluate any app you're considering.
FastFlow reads your Garmin or Apple Watch in real time and coaches you through every metabolic stage.
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