Miscellaneous

This is for when I'm closing tabs and want to put a link that should go here somewhere:

 * https://www.howardluksmd.com/zone-2-hr-training-live-longer-less-injury/ - exercise, zone 2, cardiac drift, and more
 * https://www.nutritiousmovement.com/give-your-heart-a-leg-up/ - using your calves for heart health (walking, biking)

things i want to add

 * overactive autoimmune response as an evolutionary adaptive feature in times of lots of disease (eg plague)