Holy moly this was good!
I learned a tonne!
The Physiology and Biomarkers of Recovery
@doctorinigo always makes it easier to understand complex concepts.
@david, huge thank you to making data so much easier to analyse and track thanks to Intervals. For me, everything else is either too little, wrong, or far too much (noise). 
looking forward to picking it back up on Friday mornings ride if I cant before.