Show me the paper where there is a statement that the algorithms can be used for everyone for training planning or even one paper about the correlation of HRV and running stress.
If there would be any paper out there which can proof the correlation the you need IDEAL sensors. Especially the Garmin sensors are very bad.
Then show me the science paper about a specific Garmin device test. Because the sensors and the implementation matters a lot. I am sure there is no paper out there.
But I can show you a very new science study - not paid from Garmin or Firstbeat - about the correlation of training load and hrv: "Crucially, changes in heart rate variability neither follow training load nor intensity at the individual level CONCLUSIONS: Heart rate variability did not seem to be a reliable proxy of training load and/or intensity as many previous reports have suggested, even if training conditions changed dramatically overnight."
PURPOSE: The COVID-19 crisis also affected elite sport severely, as elite athletes either stopped or drastically reduced their training regimen due to the lack of competitions and the mandatory lockdown. The aim of this study was to test whether hear...
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