Graduation Date
Spring 2020
Document Type
Thesis
Program
Master of Science degree with a major in Kinesiology, option Exercise Science
Committee Chair Name
Dr. Justus D. Ortega
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Dr. Whitney Ogle
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Dr. Jill Pawlowski
Subject Categories
Kinesiology
Abstract
The Dynamic Similarity hypothesis suggests gravitational and inertial forces plays a role in determining preferred transition speed (PTS) for walk to run transitions (WRT) and run to walk transitions (RWT), and that humans prefer to transition gait when the ratio of inertial force (IF) to gravitational force (GF) (i.e. Froude #) is ~0.5. Purpose: To investigate the effect of gravitational and inertial forces on PTS, Froude # (Fr) and kinematics for both WRT and RWT. Methods: Twelve healthy adults (9 M, 3 F) performed WRT and RWT trials on a treadmill across seven combinations of altered body weight (BW) and body mass (BM). Participants performed PTS at 1.0BM/1.0BW, 0.70 and 0.85 BW/1.0 BM (-GF), 1.15 and 1.30 BM/1.0 BW (+IF), and 1.15 and 1.30 of both BW and BM (+GF+IF). For each condition, we determined PTS by increasing speed (WRT) or decreasing speed (RWT) by 0.09 m/s every 30 seconds. Results: Neither +IF or +GF+IF affected WRT speed (p>.05). +GF+IF did not affect the Fr at WRT (p=.135). For RWT, PTS did not change due to -GF (p=.263), +IF (p=.658) or +GF+IF (p=.202). Yet, -GF and +IF increased RWT Fr (pFr of RWT (p=.426). Conclusion: WRT speed and Fr are influenced by changes in gravitational forces but are unaffected by changes in inertial forces or changes in both gravitational and inertial forces. The relation between gravitational and inertial forces did not appear to influence RWT speed but did affect the RWT Fr.
Citation Style
APA
Recommended Citation
Frakes, Nathan, "The independence effects of gravitational and inertial forces on gait transitions in humans" (2020). Cal Poly Humboldt theses and projects. 361.
https://digitalcommons.humboldt.edu/etd/361