Nurses' steps, distance traveled, and perceived physical demands in a three-shift schedule.

"Declarations Ethics approval and consent to participateThe study was approved by the Institutional Review Board (IRB No. 1701/001-002) of Seoul National University. This study was conducted in accordance with the principles of the Declaration of Helsinki and the guidelines provided by the IRB. Nurses voluntarily participated in the study and completed a consent form prior to answering the questionnaires. Consent for publicationNot applicable. Competing interestsThe authors declare that they have no financial or non-financial competing interests. Competing interests The authors declare that they have no financial or non-financial competing interests."

"Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors."