1. Some considerations on readiness scores, prompted by @DrSianAllen

Similarly to what I discussed in the blog about HRV and sleep ( https://medium.com/@altini_marco/what-you-need-to-know-about-heart-rate-variability-hrv-data-collected-during-the-night-eb3913ffdcf), the main issue is that we move from measuring to estimating, and overlook the implications.

A thread

2. We measure parameters representative of recovery (HR, HRV, breathing rate, etc.) but then we estimate the effect of activity (on e.g. muscular soreness) and sleep quality on "recovery" to compute a readiness score that should be "cumulative of everything"

3. The reality of course is that this can never be accurate (no matter how you measure or estimate activity: exercise HR, power, acceleration, etc.). You are not measuring your muscles response the way you are measuring your heart response

4. Now say your readiness score includes sleep, then you penalize twice your score if your physiology was actually impaired or you penalize it for no reason if your physiology was okay. Get it? If your poor sleep did create issues, it will be reflected in your physiology

5. I understand the reasoning behind the overall score as well as the "business value", but this method is flawed because you start from a true physiological response (HR, HRV, etc.) and confound it with estimated activity or sleep quality. These parameters are not all equal

6. The holistic view (provided by a wearable) is a myth. A wearable has no idea of muscle damage and context. Sleep quality is inherently linked to night physiological data, etc. Any readiness score that includes these can only be a toy (in my opinion!)

7. This does not mean that you should not consider activity or sleep of course, but looking at actual physiological data and how it deviates from your normal + subjective feeling + training separately seems to me a much better idea than combining them in a "readiness score"

8. It is fine to focus on one aspect with a specific scope, instead of pretending to know it all (which is just not possible). Hopefully, this makes sense to others as well.