A Comparison of Trunk Muscle Activation: Ab Circle vs. Traditional Modalities
Bibliographic record
Abstract
The purpose of this study was to compare the activation of the rectus abdominis (RA), external oblique abdominis (EO), lower abdominal stabilizers (LASs), and lumbar erector spinae (LES) during performance of 3 traditional trunk exercises vs. exercise on the Ab Circle device. Surface electromyography was used to assess 12 subjects (6 men, 6 women) for 6 exercise conditions, including: abdominal crunch, side bridge, quadruped, and Ab Circle levels 1-3. For the RA, the abdominal crunch elicited significantly greater activity vs. the Ab Circle level 1, and the side bridge elicited significantly greater activity vs. the Ab Circle levels 1 and 2. For the EO, the side bridge elicited significantly greater activity vs. the quadruped. No significant differences were noted between conditions for the LASs. For the LES, the side bridge and quadruped elicited significantly greater activity vs. the abdominal crunch. The results of this study indicate that the anterior, posterior, and lateral trunk musculature can be activated to similar or even greater levels by performing the 3 traditional trunk exercises vs. the Ab Circle. This was particularly evident for the side bridge exercise, which elicited significantly greater activity of the RA vs. the Ab Circle levels 1 and 2, and elicited similar activity of the EO, LASs, and LES at all 3 Ab Circle levels.
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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 | 0.001 |
| 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) | 0.003 | 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".