Figure 1
Figure 2
Data collection steps_
| Preparation | Recruitment and screening |
|---|---|
| Completion of informed consent and PAR-Q | |
| General instructions | |
| Demographic and pre-efficacy questionnaire | |
| Video of plank demonstration | |
| Trial one | Completion of first plank |
| 3 min rest period | Efficacy for second plank |
| Perceptions of peer norms for second plank | |
| Normative information prompt according to group assignment | |
| Repeat efficacy for second plank | |
| Trail two | Completion of second plank |
| Post-efficacy for plank | |
| Post surveys | Manipulation check for groups who received feedback |
Mean values and standard deviations for study variables_
| Variable | Positive norm condition mean values (SD) | Negative norm condition mean values (SD) | Control condition mean values (SD) | Grand mean values (SD) |
|---|---|---|---|---|
| Initial plank (s) | 106.04 (53.90) | 114.50 (42.21) | 98.89 (32.55) | 106.48 (43.80) |
| Second plank (s) | 101.29 (44.17) | 89.22 (31.98) | 83.95 (27.47) | 91.488 (35.66) |
| Pre-manipulation plank self-efficacy | 62.29 (23.64) | 67.47 (20.26) | 59.47 (26.03) | 63.08 (23.50) |
| Post-manipulation plank self-efficacy | 59.88 (19.23) | 56.41 (20.92) | 52.82 (24.72) | 56.37 (21.72) |
| Pre-manipulation plank two self-efficacy | 48.71 (20.13) | 50.82 (16.42) | 47.06 (19.62) | 48.86 (18.67) |
| Post-manipulation plank two self-efficacy | 57.71 (18.72) | 49.70 (17.71) | 47.47 (19.24) | 51.63 (18.91) |
Perceptions of peer’s second plank performance_
| What do you think happened when others like you performed the second plank? | Number of responses |
|---|---|
| Decreased by 40% | 6 (5.9%) |
| Decreased by 20% | 40 (39.2%) |
| Decreased by 10% | 42 (41.2%) |
| Same amount | 8 (7.8%) |
| Increased by 10% | 5 (4.9%) |
| Increased by 20% | 1 (1%) |
| Increased by 40% | 0 (0%) |