However, results from a recently performed case study on a Dutch individual, who holds several world records with regard to withstanding extreme cold, suggest otherwise (10). It was shown that this individual was able to voluntarily activate the sympathetic nervous system through a self-developed method involving meditation, exposure to cold, and breathing techniques.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4034215/
Long story but he was injected directly with flu bacterial from patients in hospital with authorities present as witness :
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4034215/
Long story but he was injected directly with flu bacterial from patients in hospital with authorities present as witness :
