An Israeli study tracked vitals before and after vaccination using wearable chest sensors.
My take: Whereas COVID is fairly non-lethal in younger populations, vaccines could potentially have higher rates of side effects in younger people. The study also adds to evidence that cumulative spike protein exposure causes health problems and that less exposure is better.
We identify continuous and significant changes following vaccine administration in nearly all vitals. Markedly, these changes are observed even in presumably asymptomatic participants who did not report any local or systemic reaction. Changes in vitals are more apparent at night, in younger participants, and in participants following the second vaccine dose.