This volume presents a collection of peer-reviewed papers on several areas in the field of biomechanics, including biofabrication; biomaterials; cardiovascular biomechanics, biofluids and hemodynamics; biomechanics of the injury/impact; biomechanics of rehabilitation; sports biomechanics; biomechanics of the skull and spine; biomechanics of the musculoskeletal system; biomechanics orofacial; orthopaedic biomechanics; experimental and numerical biomechanics; tissue engineering, and biomedical devices. A collection of novelties and research outcomes presented at the 9th National Biomechanics Congress (CNB 2021, 19-20 February, Porto, Portugal), this book reflects the enthusiasm and intense activity of the Portuguese biomechanical community, as well as the multidisciplinary character of the field. The National Congress of Biomechanics (CNB) is a scientific meeting organized in Portugal under the auspices of the Portuguese Biomechanical Society (SPB).