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The variation between your heartbeats, and what the research says it reveals about recovery.
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The ScienceYour heart rate at 9am on a Tuesday is not your resting heart rate. It is your heart rate at 9am on a Tuesday.
The ScienceA drop in the first few weeks is common, and it usually has a straightforward explanation. Here is what the data tends to do, and what is worth raising with your doctor.
The ScienceYour nervous system does not distinguish between a hard training session and a hard week. Both show up in the same number.
The ScienceA chest strap, a wrist wearable, or your phone camera. Each uses different technology, measures at different moments, and gives you a different kind of data.
The ScienceNo screen, no subscription, no nightly charge. Every one of those is a decision with a reason behind it.
The ScienceThe four bands are calibrated to your personal baseline, not to a population average. Here is what each one is telling you.
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