 The study aimed to characterize physiologic changes in response to COVID-19 vaccination in a small cohort of participants using a wearable device, Woopstrap 3.0. The primary outcomes were percent change from baseline in heart rate variability, HRV, resting heart rate, RHR, and respiratory rate, RR. Secondary outcomes were percent change from baseline in total rapid eye movement and deep sleep. The study found that HRV decreased on day one following administration of the first vaccine dose and second vaccine dose, with no significant changes in RHR or RR. Sleep duration initially decreased following each dose with a subsequent increase thereafter. Increased sleep prior to vaccination was associated with a greater change in HRV. The study raises the possibility that increased sleep prior to vaccination may impact physiologic responses and may be a modifiable way to increase vaccine response. This article was authored by Alexander G. Hadjiksok, Kara M. D. Joseph, Brinny Bent, and others. We are article.tv, links in the description below.