What is the most accurate smartwatch for tracking heart rate zones during marathon training according to recent expert tests.
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What is the most accurate smartwatch for tracking heart rate zones during marathon training according to recent expert tests.
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2026 expert test smartwatch optical heart rate accuracy running watches heart rate zones marathon training comparisonGoogle ↗
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2026 expert test smartwatch optical heart rate accuracy running watches heart rate zones marathon training comparison Google ↗
- The Best GPS Watches of 2026 · outdoorgearlab.com
- I ran a half marathon with the Apple Watch Ultra 3 vs Garmin Forerunner 970 to test the GPS and heart rate accuracy — here’s the winner · tomsguide.com
- I tested the Apple Watch 12’s heart rate accuracy vs a chest strap for running, cycling, HIIT and strength workouts — here's my verdict · tomsguide.com
- Heart Rate Monitors: How to Choose & Use · rei.com