Myocardial Response to Incremental Exercise in Endurance‐Trained Athletes: Influence of Heart Rate, Contractility and the Frank‐Starling Effect
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
Recent evidence indicates that endurance-trained athletes are able to increase their stroke volume (SV) throughout incremental upright exercise, probably due to a progressively greater effect of the Frank-Starling mechanism. This is contrary to the widely held belief that SV reaches a plateau at a submaximal heart rate (irrespective of fitness level), owing to a limitation in the time for diastolic filling. The purpose of this investigation was to evaluate whether endurance-trained athletes rely on a progressively greater effect of the Frank-Starling mechanism throughout incremental exercise. A secondary purpose was to evaluate the effects of postural position on the cardiovascular responses to incremental exercise. Ten male cyclists participated in this investigation. Left ventricular function was assessed throughout incremental exercise in the supine and upright positions (counterbalanced) using radionuclide ventriculography. Stroke volume increased in a linear fashion during incremental exercise in both the upright and supine positions. The increases in cardiac output (Q) throughout incremental to maximal exercise (in both the supine and upright positions) were significantly related to changes in heart rate, myocardial contractility and the Frank-Starling mechanism. Percentage changes in end-diastolic volume and SV were significantly greater in the upright position versus the supine position, reflecting an increased reliance on the Frank-Starling effect to increase Q. We conclude from this investigation that highly trained endurance athletes are able to make progressively increasing usage of the Frank-Starling effect throughout incremental exercise. Postural position has a significant effect on the relative contribution of heart rate, myocardial contractility and the Frank-Starling mechanism to the increase in Q during exercise conditions.
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) | 0.001 | 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 it