Monitoring Trends in Physiological variables

[Ale Martinez]

I uploaded a GoldenCheetah a new User Chart for tracking HRV and HR at rest to CloudDB, but since it may be an interesting example of the flexibility of User Charts and an useful framework to track other physiological measures, also added an explanation to the wiki: https://github.com/GoldenCheetah/GoldenCheetah/wiki/HRV#monitoring-trends

Feel free to experiment and to adapt to your needs.

Cheers, Ale.