Recruitment and Deoxygenation of Selected Respiratory and Skeletal Muscles During Incremental Loading in Stable COPD Patients
Bibliographic record
Abstract
PURPOSE: To evaluate changes in oxygenated (O2Hb), deoxygenated (HHb), and total hemoglobin (tHb) of the sternocleidomastoid (SCM), parasternal (PS), biceps (BC), and tibialis anterior (TA) using near-infrared spectroscopy during incremental loading of the inspiratory muscles and the elbow flexors in people with stable chronic obstructive pulmonary disease. METHODS: Fifteen participants with obstructive pulmonary disease were recruited in a repeated-measures crossover design. Near-infrared spectroscopy optodes were applied over the SCM, PS, BC, and TA to measure O2Hb, HHb, and tHb. Participants were randomly assigned to perform incremental inspiratory threshold loading or elbow flexor loading that imposed higher loads every 2 minutes until task failure. At least 1 week later, participants performed the other test. Arterial oxygen saturation (SpO2) was monitored continuously. RESULTS: O2Hb of the main agonist muscles, SCM and BC, decreased compared with the other muscles during inspiratory threshold loading and elbow flexor loading, respectively. SCM O2Hb and BC O2Hb decreased at higher loads compared with baseline. SCM tHb and HHb increased, whereas TA tHb decreased during inspiratory threshold loading. tHb did not change among any muscles during elbow flexor loading. SpO2 did not change from baseline to task failure. CONCLUSIONS: Our data suggest that the SCM was recruited progressively during incremental inspiratory threshold loading; however, O2Hb was not maintained in this muscle. Similarly, O2Hb was not maintained in the biceps during elbow flexor loading. This regional deoxygenation in SCM and BC during incremental loading protocols was not reflected by a decrease in SpO2.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".