Publications Archives - Page 28 of 32 - Neuromechanics & Mobility Lab

R Klemetti, KM Steele, P Moilanen, J Avela, J Timonen, (2014) “Contributions of individual muscles to the sagittal- and frontal-plane angular accelerations of the trunk in walking.” Journal of Biomechanics

Dr. Steele JournalArticle, MotorControl April 25, 2014October 12, 2021Simulation

Journal article accepted in Journal of Biomechanics:

Contributions of individual muscles to the sagittal- and frontal-plane angular accelerations of the trunk in walking.

This study was conducted to analyze the unimpaired control of the trunk during walking. Studying the unimpaired control of the trunk reveals characteristics of good control. These characteristics can be pursued in the rehabilitation of impaired control. Impaired control of the trunk during walking is associated with aging and many movement disorders. This is a concern as it is considered to increase fall risk. Muscles that contribute to the trunk control in normal walking may also contribute to it under perturbation circumstances, attempting to prevent an impending fall. Knowledge of such muscles can be used to rehabilitate impaired control of the trunk. Here, angular accelerations of the trunk induced by individual muscles, in the sagittal and frontal planes, were calculated using 3D muscle-driven simulations of seven young healthy subjects walking at free speed. Analysis of the simulations demonstrated that the abdominal and back muscles displayed large contributions throughout the gait cycle both in the sagittal and frontal planes. Proximal lower-limb muscles contributed more than distal muscles in the sagittal plane, while both proximal and distal muscles showed large contributions in the frontal plane. Along with the stance-limb muscles, the swing-limb muscles also exhibited considerable contribution. The gluteus medius was found to be an important individual frontal-plane control muscle; enhancing its function in pathologies could ameliorate gait by attenuating trunk sway. In addition, since gravity appreciably accelerated the trunk in the frontal plane, it may engender excessive trunk sway in pathologies. PDF

KM Steele, S Brunhaver, SD Sheppard (2014) “Feedback from in-class worksheets and discussion improves performance on the Statics Concept Inventory.” International Journal of Engineering Education

Dr. Steele JournalArticle January 25, 2014October 12, 2021Teaching

Journal article accepted in International Journal of Engineering Education:

Feedback from in-class worksheets and discussion improves performance on the Statics Concept Inventory.

The Statics Concept Inventory (SCI) is used to evaluate students’ conceptual understanding in introductory mechanics courses. Previous studies have shown that although performance on the SCI improves at the end of a course, performance is often still unsatisfactory with scores well below 100%. In this study, we sought to determine if providing feedback on conceptual topics through in-class worksheets and discussion would improve students’ performance on the SCI. To test this hypothesis, we designed eight multiple-choice worksheets, each inspired by a different topic on the SCI, for use during an introductory mechanics course. In order to evaluate the impact of the worksheets on SCI performance, we divided the eight worksheets into two groups and each group of worksheets was deployed in a different offering of the course. Each worksheet was completed at the end of a class period and, at the beginning of the next class period, the instructor led a discussion of the results and common misconceptions on each worksheet. Students took the SCI at the beginning and end of the course and the change in SCI scores for topics with and without worksheets were compared. Results from both course offerings indicated that the in-class worksheets were effective at improving performance on the SCI, as SCI scores improved significantly more for topics that had worksheets than the topics that did not have worksheets. Furthermore, overall SCI performance at the end of each course was greater than in previous courses. These results suggest that a quick and easy-to-implement addition to the curriculum using in-class worksheets and next-class discussion were effective at providing feedback on conceptual topics, exposing misconceptions, and improving performance on the SCI. The worksheets developed as part of this study are available on-line for other instructors to use (http://del.stanford.edu). The SCI is also free to use and can be found at cihub.org. PDF