Effect of oestrogen and progesterone on hypoxic exercise ventilation and respiratory muscle recruitment: considerations of the menstrual cycle and post-menopause
Bibliographic record
Abstract
We tested the hypothesis that high oestrogen [E<sub>2</sub>] and progesterone [P] increase minute ventilation (V̇<sub>E</sub>) and work of breathing (WB) during hypoxic exercise in the midluteal (ML) compared to the early follicular (EF) phase of the menstrual cycle, and in post-menopausal females using or not using hormone replacement therapies (HRT; non-HRT). Young (YF: n=11, 24±4y) and older females (OF non-HRT: n=10, 58±4y; HRT: n=7, 59±2y) completed pulmonary function and a graded cycle test to determine maximal oxygen consumption (V̇O<sub>2</sub>max: YF=51±6; OF non-HRT=45±10; HRT=35±8ml/kg/min). On experimental days, serum [P] and [E<sub>2</sub>] were measured prior to insertion of gastric and oesophageal balloon catheters, and 5 min of cycling at 70% peak power (two trials ea. in normoxia and hypoxia, FIO<sub>2</sub>=0.15). Ribcage (RM<sub>RC</sub>) and abdominal (RM<sub>AB</sub>) respiratory muscle (RM) recruitment were determined with optoelectronic plethysmography. OF were tested at any time, and YF were tested in the EF ([P]=1.1±1.6ng/ml, p<0.001; [E<sub>2</sub>]=197.7±134.8pg/ml, p=0.002) and ML phase ([P]=29.6±15.2ng/ml; [E<sub>2</sub>]=514.8±249.8pg/ml). EF and ML hypoxic exercise V̇<sub>E</sub> (EF=86±18; ML=90±21L/min, p=0.315), WB (EF=132±62; ML=123±56J/min, p=0.151) and RM recruitment (RM<sub>RC</sub> & RM<sub>AB</sub>=∆1±0%) were similar. There was a moderate correlation between hypoxic exercise ∆V̇<sub>E</sub>/V̇O<sub>2</sub> and ∆[P] (r=0.685, p=0.029). A significant interaction of condition and HRT was present in OF (hypoxic V̇<sub>E</sub> non-HRT=83.2±18.5, HRT=66.9±12.3L/min, p=0.006). Our findings suggest high [P] increases V̇<sub>E</sub> relative to low [P] during hypoxic exercise in YF. Contrary to our hypothesis, in OF HRT use may blunt hypoxic V̇<sub>E</sub> (funding:NSERC).
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| 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".