The number of purposeful headers female youth soccer players experience during games depends on player age but not player position
Bibliographic record
Abstract
Purpose: The aim of this study was to describe the frequency and characteristics of purposeful soccer heading in youth players based on age, position, and head impact location.Methods: Game video was recorded for three female youth teams [under-13 (U13), under-14 (U14), and under-15 (U15)] for an entire season. Purposeful headers were categorized for these three teams and their opposition.Results: The median number of headers experienced during games was one, and the minimum number of headers was zero. The maximum number of headers performed during a game by a U13 player was eight, and nine for U14 and U15 players. There were statistically significant differences in the number of headers performed in the different age groups (p < 0.05), but no significant differences between player position (p > 0.05). There was no significant association between head impact location and game scenario (p > 0.05).Conclusions: Our study shows that youth players frequently head the ball during games. This information may guide data-driven approaches regarding heading restrictions in youth soccer.
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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 | 0.000 |
| 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 | 0.002 |
| 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".