Fatigue and recovery of power and isometric torque following isotonic knee extensions
Bibliographic record
Abstract
The purpose of this study was to assess fatigue and recovery of isotonic power and isometric contractile properties after a series of maximal isotonic contractions. Using a Biodex dynamometer, 13 men [26 yr (SD 3)] performed isotonic [50% of isometric maximal voluntary contraction (MVC) every 1.2 s through 75 degrees range of motion] single-limb knee extensions at the fastest velocity they could achieve until velocity was reduced by 35%. Time to task failure was 38 s, and, compared with baseline, power declined by approximately 42% [741.0 (SD 106.0) vs. 426.5 W (SD 60.3) at task failure], and MVC declined by approximately 26% [267.3 (SD 42.5) vs. 198.4 N.m (SD 45.7) at task failure]. Power recovered by 5 min, whereas MVC did not recover, and at 10 min was only approximately 85% of baseline. Isometric MVC motor unit activation was approximately 95% at rest and was unchanged at task failure (approximately 96%), but a small amount of failure was apparent between 1.5 and 10 min of recovery (approximately 87 to approximately 91%). Half relaxation time measured from a 50-Hz isometric tetanus was significantly prolonged by approximately 33% immediately after task failure but recovered by 1.5 min. A decline in the 10- to 50-Hz ratio of the evoked isometric contractions was observed at 5 and 10 min of recovery, which suggests excitation-contraction coupling impairment. Changes in velocity and half relaxation time during the protocol were strongly and negatively correlated (r = -0.85). Thus mainly peripheral mechanisms were implicated in the substantial depression but relatively fast recovery of isotonic power. Furthermore, isometric muscle contractile properties were related to some, but not all, changes in isotonic function.
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 | 0.000 |
| 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".