TABLE 3.
Mean and standard deviation (SD) at pre- and post-test for each condition; and beta-coefficient for changes within conditions and time-by-condition interactions.
| Conditions | Change within conditions (Post minus Pre) | Change in post-pre between conditions | ||||||||||
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| Pre-test | Post-test | SOCIAL | WALK | SRA | WALK-SOCIAL | SRA-SOCIAL | WALK-SRA | |||||
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| SOCIAL | WALK | SRA | SOCIAL | WALK | SRA | Beta | Beta | Beta | Beta | Beta | Beta | |
| Cognitive function | ||||||||||||
| 1-back ACC (score) | 39.0 (2.5) | 39.2 (1.2) | 38.7 (2.1) | 39.2 (1.1) | 39.2 (1.2) | 39.4 (1.0) | 0.2 | 0.1 | 0.7 | −0.1 | 0.5 | −0.6 |
| 1-back RT (ms) | 551.9 (64.3) | 567.6 (95.7) | 576.7 (104.3) | 562.1 (98.0) | 565.1 (95.0) | 584.7 (97.2) | 10.2 | −2.5 | 8.0 | −12.7 | −2.2 | −10.5 |
| 2-back ACC (score) | 75.0 (6.6) | 76.9 (3.2) | 75.2 (5.0) | 76.8 (3.3) | 76.2 (2.7) | 76.0 (3.9) | 1.8 | −0.8 | 0.8 | −2.6 | −1.1 | −1.5 |
| 2-back RT (ms) | 605.5 (105.2) | 594.3 (101.9) | 618.8 (104.2) | 611.2 (104.0) | 585.4 (106.9) | 624.0 (115.7) | 5.6 | −8.9 | 5.2 | −14.5 | −0.5 | −14.0 |
| 3-back ACC (score) | 68.9 (6.4) | 69.3 (5.9) | 68.8 (9.1) | 68.2 (6.3) | 68.3 (7.8) | 67.8 (7.7) | −0.7 | −1.0 | −1.1 | −0.3 | −0.4 | 0.1 |
| 3-back RT (ms) | 702.9 (98.3) | 707.7 (106.8) | 703.2 (120.8) | 712.5 (100.1) | 670.4 (118.8) | 700.3 (122.0) | 9.6 | −37.3* | −2.9 | −46.9 | −12.5 | −34.4 |
| Positive affects (score) | 31.2 (6.6) | 28.1 (7.1) | 29.7 (6.7) | 28.0 (7.1) | 31.2 (8.4) | 28.8 (7.6) | −3.2 | 3.1 | −0.8 | 6.2* | 2.3 | 3.9 |
| Negative affects (score) | 12.0 (2.3) | 12.9 (3.9) | 11.4 (2.3) | 11.8 (2.1) | 11.6 (2.7) | 11.2 (1.7) | −0.2 | −1.3 | −0.8 | −1.1 | −0.1 | −1.0 |
| KSS-sleepiness (score) | 4.5 (2.1) | 4.9 (1.9) | 4.4 (1.9) | 4.9 (1.7) | 3.9 (1.8) | 4.2 (1.5) | 0.4 | −1.0 | −0.2 | −1.4 | −0.5 | −0.8 |
| Alertness (cm) | 5.4 (2.3) | 4.7 (2.6) | 5.3 (2.4) | 4.9 (2.4) | 6.4 (2.5) | 5.7 (2.6) | −0.5 | 1.7** | −0.2 | 2.2* | 0.8 | 1.4 |
| Stress (cortisol ng/ml) | 7.2 (3.5) | 4.8 (2.1) | 4.6 (2.1) | 3.2 (1.8) | 3.2 (2.8) | 2.8 (2.0) | −4.0** | −1.6* | −1.7** | 2.5* | 2.3* | 0.2 |
SOCIAL, social break condition; WALK, walking break condition; SRA, simple resistance activity break condition; ACC, accuracy; RT, reaction time; Positive and negative affects taken from the PANAS questionnaire; Alertness ranges from 0 “not at all” to 10 “completely alert” (highest) cm; KSS, Karolinska sleepiness questionnaire, ranges from 1 “extremely alert” to 9 “very sleepy, great effort to keep awake, fighting sleep.”
*p ≤ 0.05; **p ≤ 0.001.