The contribution of body part angular momentum (BPAM) to whole body angular momentum (WBAM) in the frontal plane during walking differs across age groups. We investigated age related differences in BPAM and WBAM during walking. We used marker coordinate data from a publicly available database for 54 individuals aged 20-30 years and 78 aged 60-70 years. Angular momentum in the frontal plane was calculated as the sum of the translational component and the rotational component for each segment. The angular momentum of each segment was categorized into five BPAM: right and left lower limbs (foot, shank, and thigh), right and left arms (hand, forearm, and upper arm), and torso (head, thorax, and pelvis). BPAM at WBAM peak frames during stride cycles was compared between older and younger adults. The peak WBAM, angular momentum of the stance-and swing side upper limbs, and torso in older adults was significantly larger than that in younger adults, with increases of 74.6% in the stance-side upper limb, 127.5% in the swing-side upper limb, and 30.9% in the torso. These results suggest that interventions aimed at improving torso control could decrease the amplitude of WBAM in the frontal plane in older adults.
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http://dx.doi.org/10.1038/s41598-024-76814-y | DOI Listing |
Light Sci Appl
January 2025
Institute of Photonics, Leibniz University Hannover, 30167, Hannover, Germany.
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View Article and Find Full Text PDFLight Sci Appl
January 2025
Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Cité and CNRS, Paris, 75013, France.
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View Article and Find Full Text PDFA 1645 nm end-pumped dual-channel Er:YAG vector laser that could generate two cylindrical vector (CV) beams simultaneously with different polarization orders is demonstrated. The laser is designed in a two-arm structure, wherein each arm places a q-plate (QP) to introduce intra-cavity spin-orbital angular momentum conversion, leading to the oscillation of two various CV modes in two arms, and finally output along two directions, respectively. The favorable experimental results illustrate high power stability and polarization mode purity.
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