Discriminating features of ground reaction forces in overweight old and young adults during walking using functional principal component analysis

Hyun Kyung Kim; Xiongtao Dai; Shiuan-Huei Lu; Tung-Wu Lu; Li-Shan Chou

doi:10.1016/j.gaitpost.2022.03.012

Discriminating features of ground reaction forces in overweight old and young adults during walking using functional principal component analysis

Gait Posture. 2022 May:94:166-172. doi: 10.1016/j.gaitpost.2022.03.012. Epub 2022 Mar 21.

Authors

Hyun Kyung Kim¹, Xiongtao Dai², Shiuan-Huei Lu³, Tung-Wu Lu³, Li-Shan Chou⁴

Affiliations

¹ Department of Kinesiology, Iowa State University, Ames, IA, USA.
² Department of Statistic, Iowa State University, Ames, IA, USA.
³ Department of Biomedical Engineering, National Taiwan University, Taiwan.
⁴ Department of Kinesiology, Iowa State University, Ames, IA, USA. Electronic address: chou@iastate.edu.

PMID: 35339964
DOI: 10.1016/j.gaitpost.2022.03.012

Abstract

Background: Limited attention has been paid to age- or body size-related changes in the ground reaction forces (GRF) during walking despite their strong associations with lower limb injuries and pathology.

Research question: Do the features of GRF during walking associate with age or body size?

Methods: Fifty-four participants were subdivided into four groups according to their age and body size: overweight old (n = 12), non-overweight old (n = 13), overweight young (n = 13), and non-overweight young (n = 16). Participants were asked to walk at their self-selected speeds on level ground with force plates embedded in the center of walkway. Functional principal component analysis (FPCA) was performed to extract major modes of variation and functional principal component scores (FPCs) in three-dimensional GRFs. Analysis of variance models were employed to investigate the effect of age, body size, or their interactions on the FPCs of each component of the GRF, with the adjustment to gait speed.

Results: Significant age and body size effects were observed in FPC1 across all three-dimensional GRF. Both overweight and older groups showed greater braking force after heel-strike and greater propulsive forces during pre-swing when compared to the non-overweight and younger groups, respectively. The overweight old group displayed greater medial forces during mid-stance and the overweight young group showed prominently larger medial forces during pre-swing, while non-overweight old showed a tendency of flatter medial-lateral GRF waveforms during the entire stance phase. FPC2 revealed that only body size had an effect on three-dimensional GRF with the highest FPC2 scores in the overweight old group.

Significance: Three-dimensional GRF during walking could be altered by the body size and age, which were more pronounced in the overweight and older group. The more dynamic GRF pattern with greater and/or lower peaks could be contributing factors to the increased joint load and injury rates observed in overweight aged individuals.

Keywords: Dimensionality reduction technique; Elderly; FPCA; GRF; Gait.

MeSH terms

Aged
Biomechanical Phenomena
Gait*
Humans
Overweight*
Principal Component Analysis
Walking
Young Adult