{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T09:51:21Z","timestamp":1784713881481,"version":"3.55.0"},"reference-count":30,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,22]],"date-time":"2025-11-22T00:00:00Z","timestamp":1763769600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>(1) Background: Passive rocking is commonly used to calm infants, yet its biomechanical impact on different body segments\u2014particularly dynamic loading of the head and torso\u2014remains insufficiently understood. (2) Methods: An infant doll was instrumented with IMUs placed on the head, abdomen, and gluteal region and subjected to controlled rocking in a standard infant rocker. Segmental responses were quantified using angular displacement, velocity, and acceleration, along with time\u2013frequency analyses including wavelet transforms and inter-segmental transfer functions. (3) Results: The head showed the highest angular displacements and peak accelerations, predominantly in the sagittal plane, with pronounced oscillations in the 10\u201312 Hz range. The abdomen acted as a transitional damping zone, while the gluteal region remained largely static, serving as the mechanical input point. Frequency-domain results revealed upward amplification of motion energy, suggesting inertial and potentially resonant effects that intensify loads at the head. (4) Conclusions: Although base-level motion appears gentle, signal-level analysis reveals significant dynamic amplification toward the head. These findings underscore the importance of considering frequency-dependent transmission and segmental dynamics in infant rocker design, with implications for ergonomic safety, particularly in the early stages of development.<\/jats:p>","DOI":"10.3390\/jcm14238301","type":"journal-article","created":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T16:31:54Z","timestamp":1764088314000},"page":"8301","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Frequency-Dependent Amplification of Head Motion in Infant Rockers: A Segmental IMU-Based Signal Analysis"],"prefix":"10.3390","volume":"14","author":[{"given":"Alina","family":"G\u0142owi\u0144ska","sequence":"first","affiliation":[{"name":"Independent Researcher, 74-024 Koszalin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3140-6313","authenticated-orcid":false,"given":"Sebastian","family":"Glowinski","sequence":"additional","affiliation":[{"name":"Institute of Health Sciences, Pomeranian University in Slupsk, Westerplatte 64, 76-200 Slupsk, Poland"},{"name":"Institute of Physical Culture, The State Academy of Applied Sciences in Koszalin, Le\u015bna 1, 75-582 Koszalin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1186\/s42269-022-00807-y","article-title":"Effect of facilitated rocking movement in reducing vaccination-induced pain in young infants: A randomized control trial","volume":"46","author":"Yadav","year":"2022","journal-title":"Bull. 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