IS THERE AN INTERACTION BETWEEN PHYSICAL ACTIVITY AND CALCIUM INTAKE ON BONE MINERAL STATUS DURING THE GROWING YEARS?
Bibliographic record
Abstract
Both physical activity (PA) and calcium (Ca) intake are known to be important factors in optimizing bone during the growing years; however evidence of an interactive effect of physical activity and calcium intake is sparse. PURPOSE To determine the significance of the interaction between PA and Ca intake on total body (TB), femoral neck (FN) and lumber spine (LS) bone mineral content (BMC) in growing boys and girls. METHODS 85 boys and 67 girls were assessed annually during the circumpubertal years. BMC was assessed by dual energy X-ray absorptiometry (DXA). PA was determined by the physical activity questionnaire for children (PAQ-C – 1 low, 5 high). Calcium intake values (mg/day) were obtained from dietary intake questionnaire. Biological age was defined as years from age of peak height velocity. Data were analyzed using random effects models. RESULTS No significant (p > 0.05) interactive effects of PA and Ca intake were found at any sites in either gender. In both boys and girls, when biological age, height and body mass were controlled, LS BMC was significantly influenced by PA (boys, 0.53 SEE 0.25 PAQ-C score, p < 0.05; girls, 0.91 SEE 0.32 PAQ-C score, p < 0.05). Ca intake was not a significant predictor of LS BMC (p > 0.05). No independent effects of PA or Ca intake were found in FN BMC in the girls, but in boys Ca intake was a significant predictor of FN BMC (0.00005 SEE 0.00002 mg/day, p < 0.05). PA was a significant predictor of TB BMC in girls (15.2 SEE 6.1, PAQ-C score, p < 0.05) but had no significant effect in boys. Ca intake was not a significant predictor of girls' TB BMC but was of boys (0.014 SEE 0.007 mg/day, p < 0.05). CONCLUSION Longitudinal growth models failed to identify any interactive effects of PA and Ca intake on BMC at the TB, FN or LS. In girls PA alone was a significant predictor of BMC at the LS and TB but not at the FN. In boys PA alone was a significant predictor at the LS only. In girls Ca intake did not predict BMC at any site but in boys Ca intake was a significant predictor of TB and FN BMC.
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 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 | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".