Biomechanical analysis of the relation between movement time and joint moment development during a sit-to-stand task
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
BACKGROUND: Slowness of movement is a factor that may cause a decrease of quality of daily life. Mobility in the elderly and people with movement impairments may be improved by increasing the quickness of fundamental locomotor tasks. Because it has not been revealed how much muscle strength is required to improve quickness, the purpose of this study was to reveal the relation between movement time and the required muscle strength in a sit to stand (STS) task. Previous research found that the sum of the peak hip and knee joint moments was relatively invariant throughout a range of movement patterns (Yoshioka et al., 2007, Biomedical Engineering Online 6:26). The sum of the peak hip and knee joint moment is an appropriate index to evaluate the muscle strength required for an STS task, since the effect of the movement pattern variation can be reduced, that is, the results can be evaluated purely from the viewpoint of the movement times. Therefore, the sum of the peak hip and knee joint moment was used as the index to indicate the required muscle strength. METHODS: Experimental kinematics data were collected from 11 subjects. The time at which the vertical position of the right shoulder fell outside three standard deviations of the vertical positions during the static initial posture was regarded as the start time. The time at which the vertical position fell within three standard deviations of the vertical positions during static upright standing posture was regarded as the finish time. Each movement time of the experimental movements was linearly lengthened and shortened through post-processing. Combining the experimental procedure and the post-processing, movements having various movement patterns and a wide range of movement times were obtained. The joint moment and the static and inertial components of the joint moment were calculated with an inverse dynamics method. The static component reflects the gravitational and/or external forces, while the inertial component reflects the acceleration of the body. RESULTS: The quantitative relation between the movement time and the sum of the peak hip and knee joint moments were obtained. As the STS movement time increased, the joint moments decreased exponentially and converged to the static component (1.51 approximately 1.54 N.m/kg). When the movement time was the longest (movement time: 7.0 seconds), the joint moments (1.57 N.m/kg) closely corresponded to the minimum of 1.53 N.m/kg as reported by Yoshioka et al.. CONCLUSION: The key findings of this study are as follows. (1) The minimum required joint moment for an STS task is essentially equivalent to the static component of the joint moment. (2) For fast and moderate speed movements (less than 2.5 seconds), joint moments increased exponentially as the movement speed increased. (3) For slow movements greater than 2.5 seconds, the joint moments were relatively constant. The results of this STS research has practical applications, especially in rehabilitations and exercise prescription where improved movement time is an intended target, since the required muscle strength can be quantitatively estimated.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it