Changes in Osteoprotegerin and Sclerostin Across a Training Season in Olympic Female Rowers
Bibliographic record
Abstract
Exercise training is generally associated with an increase bone mineral density (BMD) but this adaptation is reversed during extended periods of intense training. Furthermore, examination of serum markers of bone turnover has shown an unbalanced increase in bone resorption over bone formation during high volume training. However, the molecular events that precede these changes in bone turnover remain unclear. One pathway related to mechanical loading is the Wnt signalling pathway. Osteoprotegerin (OPG) is a transcription product of Wnt signalling leading to inhibition of bone resorption. Sclerostin (SOST) is an inhibitor of Wnt signalling leading to reduced formation. Therefore, the purpose of this project was to monitor changes in OPG and SOST at times of different training volumes during the pre‐Olympic training season in female rowers. Insulin like growth factor (IGF‐1) and leptin, two other factors that are sensitive to training and have been associated with Wnt signalling were also examined. Blood samples were drawn from female heavy‐weight rowers (n=15, 27.0 ± 0.8 y, 80.9 ± 1.3 kg, 179.4 ± 1.4 cm) at baseline (T1 – 11 months pre‐Olympic Games) and following 1 (T2), 2 (T3), 6 (T4), 7 (T5) and 9 months (T6). Serum was analyzed by Multiplex assays (EMD Millipore, Toronto, CAN). Total weekly training volume was recorded over the week prior to each time point. BMD was measured at multiple sites by dual energy X‐ray absorptiometry at T1 and T6. OPG decreased significantly from T2 to T6 (−28.7%, p<0.05) and SOST levels were increased at T5 compared to T6, T4, T3 and T2 (993.1 vs. 741.0, 709.3, 759.7 and 774.2 pg/mL respectively, p<0.05). IGF‐1 was not changed over time. Leptin increased from T1 to T6 (+84%, p<0.05). Weekly training volume prior to T1 through T6 was 1020, 730, 1270, 1135, 1165 and 1200 min/wk, respectively. No change in BMD was observed at any bone site from T1 to T6. Therefore, over the course of the training season, OPG concentrations decreased while leptin and SOST concentrations increased, suggesting an increased bone formation and decreased bone resorption. In summary, bone biochemical markers were affected during the pre‐Olympic training season in female rowers, but BMD remained unchanged. However, the pattern of changes in osteokines, reflecting dynamic deviations in bone remodelling were not sensitive to changes in training volume. Support or Funding Information Canadian Sports Institute
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 | 0.000 | 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) | 0.001 | 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".