The Ramadan natural experiment is interesting, this has been discussed wrt sport performance previously, eg see http://regressing.deadspin.com/is-fasting-for-ramadan-dangerous-at-the-world-cup-1598373130
The Ramadan natural experiment is interesting, this has been discussed wrt sport performance previously, eg see http://regressing.deadspin.com/is-fasting-for-ramadan-dangerous-at-the-world-cup-1598373130