Pfizer - BioNTech (BNT162b2) COVID - 19 vaccine is the first vaccine to be approved for emergency use by FDA. The most commonly reported side effect of the BNT162b2 vaccination is mild-to-moderate pain at injection site, i.e. deltoid muscle. Injection site pain may be observed during and after vaccine injection, and severity of pain may vary according to the type of vaccine, patients age, sex, level of anxiety, needle size, injection site and technique and patient positioning. Vaccination pain is one of the reasons of vaccine hesitancy and World Health Organization (WHO) recommended various measures to mitigate pain at the time of vaccination.

Exercise is one of the suggested methods to relieve the pain and anxiety in various conditions including vaccination site pain. However, we found no studies addressing injection site pain after the vaccination and pain associated with BNT162b2 vaccine. Aim of our study is to evaluate effectiveness of deltoid muscle exercises to relieve injection site pain observed after BNT162b2 vaccination.

The study was started at the designated COVID - 19 vaccination department of Bursa Yuksek Ihtisas research and training hospital Approvals was obtained from Republic of Turkey Ministry of Health and institutional review board and ethics committee and the study was conducted in concordance with Declaration of Helsinki.

Volunteers were selected among the healthy persons who admitted to our vaccination department to have BNT162b2 vaccine. Selection criteria were age being over 18, having no physical disability to perform the physical exercises given and willingness to participate in the study and sign an informed consent. People under the age of 18, patients with conditions that prevent them doing the exercises given and who did not want to participate in the study were excluded from the study.

Volunteers who accept to participate in the study, were randomized in to exercise vs. no-exercise groups according to a previously formed online randomization list. All volunteer's demographic data and vaccination status (first or second dose) were recorded. Both groups were asked to keep a five - day pain diary using numeric rating scale (NRS) and to also record any use of analgesics, any hospital admissions, any side effects other than injection site and arm pain and the time of cessation of pain.

Inclusion Criteria:

• vaccination with Bnt162b2
• having no physical disability to perform the physical exercises given
• willingness to participate in the study and sign the informed consent form

Exclusion Criteria:

• vaccination with vaccines other than Bnt162b2
• having physical disability to perform the physical exercises given
• not willing to participate in the study and sign the informed consent form