Effects Of 12-months Of Exercise Training On Determinants Of Vo2Peak In Anthracycline-treated Breast Cancer Survivors
Bibliographic record
Abstract
PURPOSE: Reduced peak oxygen uptake (V̇O2peak) is common in breast cancer (BC) survivors treated with anthracycline chemotherapy (AC). Exercise training (ExT) may be a useful therapy for addressing reduced V̇O2peak, however the mechanisms underlying changes in V̇O2peak with exercise training (ExT) during AC are unclear. We sought to evaluate the effect of ExT on the central (convective O2 delivery [QO2]) and peripheral (arterio-venous O2 difference [a-vO2diff] and skeletal muscle diffusive conductance [DmO2]) determinants of V̇O2peak in female BC survivors. METHODS: This was a secondary analysis of the BREXIT study using baseline (pre-AC) and 12-month assessments from a 12-month randomized trial comparing 3-4 sessions/wk of aerobic and resistance ExT to usual care (UC) in 104 women aged 40-75 years with stage I-III BC scheduled for AC. V̇O2peak, peak heart rate (HRpeak) and arterial O2 saturation were assessed from an upright cardiopulmonary exercise test. Peak cardiac output (Qpeak) was calculated from upright HRpeak and supine peak stroke volume (SVpeak) during exercise cardiac magnetic resonance. Hemoglobin (Hb) was measured from a venous blood sample. These measures were then used to calculate a-vO2diff, QO2 and DmO2 from previously published equations. RESULTS: Sixty-four participants completed the study with available data to calculate V̇O2peak determinants (ExT: n = 38, UC: n = 26). At 12-months, ExT had a significant effect on V̇O2peak (+0.17 L/min) due to a 0.08 L/min increase with ExT (P = 0.03) and a 0.08 L/min reduction with UC (P = 0.03). Changes in V̇O2peak were largely driven by QO2, and specifically Qpeak, that increased with ExT (+1.3 L/min, P < 0.001) and decreased with UC (-1.6 L/min, P < 0.001), resulting in a 3.0 L/min (P < 0.001) and 0.33 L/min (P < 0.001) net benefit of ExT on Qpeak and QO2, respectively. In contrast, there was a small reduction in a-vO2diff with ExT (-0.5 mL/dL, P = 0.038) and an increase with UC (+0.6 mL/dL, P = 0.042), resulting in a net decline with ExT (-1.1 mL/dL, P < 0.001). These effects were largely driven by Qpeak, as DmO2 did not change during the study. CONCLUSIONS: In early-stage BC survivors undergoing AC, treatment-induced reductions in V̇O2peak are largely driven by a decline in QO2 secondary to reduced Qpeak, which can be prevented by 12-months of structured ExT.
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 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 | 0.001 | 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 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".