Downhill Dilemma: Analyzing Joint Force on Variable Speed and Gradient
Bibliographic record
Abstract
Movement on declined slopes poses unique mechanical stresses when compared to level surfaces. Both downhill (DH) running and walking have seen large amounts of load force absorption on the knee (French 2018; Abe et.al., 2011) with some forces possibly being distributed to the hip and ankle joints. Though research is limited about lower extremity joint kinematics across all three joints. PURPOSE: To better understand the joint forces placed on the hip, knee, and ankle with variable speed and decline gradient METHODS: Nine participants (5 male and 4 female; Age = 24.09 ± 2.81 yrs; Weight = 75.12 ± 13.67 kg; Height = 1724.89 ± 68.58 mm) were asked to walk and run, in five-minute intervals on an instrumented treadmill (Bertec, Inc. Columbus, OH) at self-selected velocities. Conditions were determined in randomized order (C1 = walk flat, C2 = run flat, C3 = DH Walk, C4 = DH Run) and intervals were performed at a flat plane as well as a decline of -9°. Data collection used 8 video cameras recording at 50 hZ. (Theia, Inc., Kingston, Ontario, Canada) and analyzed using Visual 3D (C-Motion, Inc.,Germantown, MD). Data was further analyzed (using C2 vs C4 and C1 vs C3) using a repeated measure ANOVA with Tukey-b post-hoc test (family-wise α = 0.05). RESULTS: Analysis saw significant (p < 0.05) joint forces across all conditions. Highest hip and ankle forces reported in C2 (hip = -20.99±2.06 N/kg; ankle = -20.20±1.86 N/kg). Highest knee forces reported in C4 (knee = -22.07±3.0 N/kg). Highest velocity reported in C2 (2.56±0.44 m/s). CONCLUSION: The current study found C2 imposed higher forces on the ankle and hip compared to other conditions. C4 presented higher forces in the knee. Participants could self-select speeds for each condition, resulting in C2 having the fastest running speed. Evidence has suggested that higher speeds tend to increase joint forces (Schache et al., 2011) which may contribute to the findings of the current study, however, may have significance in a real-world setting. Higher speeds and joint force loading can be an indicator of lower extremity injury (French, 2018). Therefore, future research should look into DH/Flat Running and its implications on injury in an applied setting.
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.
How this classification was reachedexpand
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 | 0.000 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".