Background
Methods
Study population
Physical activity, sedentary time and sleep assessment
Cardio-respiratory fitness
Anthropometric measurements
Questionnaire data
Statistical analysis
Results
Variable | Boys (n = 376) | Girls (n = 354) | All (n = 730) |
---|---|---|---|
Age (years) | 10.0 ± 0.6 | 9.9 ± 0.6 * | 10.0 ± 0.6 |
3rd grade/4th grade | 49% / 51% | 49% / 51% | 49% / 51% |
Pubertal status (% 1/2/≥3) | 76.5 / 19.4 / 4.2 | 54.5 / 36.2 / 9.3 ** | 65.7 / 27.6 / 6.7 |
Parents born in Denmark (% 0 / 1 / 2) | 11.2 / 12.5 / 76.3 | 10.5 / 11.9 / 77.7 | 10.8 / 12.2 / 77.0 |
Highest education of household (%)1
| 4.5 / 31.7 / 40.5 / 23.2 | 5.9 / 30.9 / 40.5 / 22.7 | 5.2 / 31.3 / 40.5 / 22.9 |
Weight (kg) | 35.5 ± 7.2 | 34.5 ± 6.7 | 35.0 ± 7.0 |
Height (cm) | 142.6 ± 7.1 | 142.1 ± 7.0 | 142.4 ± 7.1 |
Body mass index Z-score2
| 0.23 ± 1.12 | 0.04 ± 1.03 * | 0.13 ± 1.08 |
Weight status (% uw/nw/ow/ob)3
| 8.3/77.8/11.5/2.4 | 12.3/75.1/11.4/1.1 | 10.2/76.5/11.5/1.8 |
Variables | n | Autumn | Winter | Spring | ICC | Bias (%) | MAPE (%) |
---|---|---|---|---|---|---|---|
Sedentary time (min/d) | 635 | 473 ± 63a
| 486 ± 59b
| 465 ± 66a ** | 0.60 | −0.4/2.5/-2.1 | 5.4/5.5/5.8 |
Screen-time (min/d)1
| 704 | 146 (102;193) | |||||
Screen-time (≤2 h/d)1,2
| 704 | 34% | |||||
Total PA (cpm) | 635 | 490 ± 135a
| 447 ± 120b
| 557 ± 175c ** | 0.47 | −1.2/-9.9/11.1 | 11.6a/13.1b/15.1c ** |
MVPA (min/d) | 635 | 49 ± 23a
| 44 ± 22b
| 57 ± 27c ** | 0.64 | −2.0/-11.1/13.1 | 17.9a/19.4ab/21.1b * |
MVPA (≥1 h/d) (%)3
| 635 | 28% | 22% | 39% ** | |||
CRF (ml/kg/min)4
| 492 | 47.5 ± 5.1a
| 48.3 ± 5.4ab
| 49.2 ± 5.8c ** | 0.74 | −1.6/-0.1/1.7 | 3.7a/3.2b/3.9a * |
Sleep duration (min/night) | 523 | 556 ± 27a
| 553 ± 28a
| 541 ± 30b ** | 0.50 | 1.2/0.5/-1.6 | 2.3a/2.2a/2.7b ** |
Variables | n | Autumn | Winter | Spring | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Weekday | Weekend | Ratio5
| Weekday | Weekend | Ratio5
| Weekday | Weekend | Ratio5
| ||
Sedentary time (min/d) | 635 | 467 ± 66 | 488 ± 88** | 1.05 | 477 ± 61 | 509 ± 82** | 1.07 | 459 ± 67 | 481 ± 94** | 1.06 |
Screen-time (min/d)1
| 704 | 120 (80;165) | 210 (135;300)** | |||||||
Screen-time (≤2 h/d)1,2
| 704 | 46% | 17%** | |||||||
Total PA (cpm) | 635 | 507 (417;614) | 400 (295;514)** | 0.84a
| 464 (388;566) | 347 (259;441)** | 0.78b
| 555 (450;671) | 460 (331;635)** | 0.92c ** |
MVPA (min/d) | 635 | 50 (34;71) | 28 (16;47)** | 0.68a
| 46 (32;66) | 24 (12;39)** | 0.63a
| 56 (38;78) | 40 (21;62)** | 0.83b ** |
MVPA (≥1 h/d)3
| 635 | 37% | 15%** | 0.41 | 33% | 9%** | 0.28 | 45% | 27%** | 0.60 * |
Sleep duration (min/night)4
| 523 | 559 ± 28 | 549 ± 48** | 0.99 | 554 ± 31 | 549 ± 48* | 1.00 | 543 ± 32 | 536 ± 55* | 0.99 |
Variable1
| n | Moderate-to-vigorous physical activity (min/day) (n = 635) | Sedentary time (min/day) (n = 635) | Sleep duration (min/night) (n = 523) | Cardio-respiratory fitness (ml/kg/min) (n = 492) | ||||
---|---|---|---|---|---|---|---|---|---|
B (95%CI) |
P
| B (95%CI) |
P
| B (95%CI) |
P
| B (95%CI) |
p
| ||
Age (years) | 730 | −2.7 (−4.5;-0.8) | 0.0463
| 27.8 (21.5;34.1) | <0.001 | −10.2 (−13.4;-7.1) | <0.001 | 0.8 (0.1;1.5) | 0.03 |
Grade | 730 | ||||||||
3rd graders | 359 | Reference | Reference | Reference | Reference | ||||
4th graders | 371 | −5.4 (−8.7;-2.1) | <0.001 | 32.4 (24.4;40.4) | <0.001 | −13.6 (−17.5;-9.6) | <0.001 | −0.1 (−1.0;0.8) | 0.87 |
Pubertal status | 706 | ||||||||
1 | 464 | Reference | Reference | Reference | Reference | ||||
≥2 | 242 | −7.5 (−11.0;-3.9) | <0.001 | 12.0 (3.0;21.0) | 0.01 | −7.2 (−11.6;-2.9) | 0.001 | −2.5 (−3.4;-1.6) | <0.001 |
Gender | 730 | ||||||||
Girls | 354 | Reference | Reference | Reference | Reference | ||||
Boys | 376 | 19.9 (16.9;22.9) | <0.001 | −0.3 (−8.7;8.1) | 0.95 | −5.1 (−9.2;-1.0) | 0.01 | 8.0 (7.5;8.5) | <0.001 |
Parents born in Denmark2
| 730 | ||||||||
0 | 79 | Reference | Reference | Reference | Reference | ||||
1 | 89 | 2.3 (−4.8;9.4) | 0.52 | 12.6 (−5.2;30.4) | 0.16 | 20.8 (11.2;30.5) | <0.001 | 1.3 (−0.7;3.2) | 0.20 |
2 | 562 | −2.4 (−8.0;3.2) | 0.40 | 13.5 (−0.4;27.4) | 0.064
| 19.2 (11.1;30.5) | <0.001 | 0.1 (−1.5;1.7) | 0.89 |
Highest education of parents2
| 728 | ||||||||
≤10 years | 38 | Reference | Reference | Reference | Reference | ||||
11 - 12 years | 228 | −3.1 (−11.6;5.3) | 0.46 | 13.0 (−7.9;34.0) | 0.22 | 24.4 (12.9;35.9) | <0.001 | 0.8 (−1.3;3.0) | 0.45 |
13 - 16 years | 295 | −4.0 (−12.2;4.3) | 0.35 | 22.5 (1.9;43.1) | 0.03 | 26.0 (14.7;37.4) | <0.001 | 1.1 (−1.1;3.3) | 0.31 |
≥17 years | 167 | −1.3 (−9.9;7.2) | 0.76 | 24.0 (2.7;45.3) | 0.03 | 23.0 (11.4;34.6) | <0.001 | 1.5 (−0.7;3.7) | 0.20 |
Sedentary time (min/day) | Screen time (min/day) | Total PA (cpm) | MVPA (min/day) | CRF (ml/kg/day) | |
---|---|---|---|---|---|
Screen time (min/day)1
| 0.18 / 0.17 | ||||
Total PA (cpm) | −0.70 / -0.69 | −0.13 / -0.11 | |||
MVPA (min/day) | −0.49 / -0.49 | −0.08 / -0.06 | 0.89 / 0.91 | ||
CRF (ml/kg/day) | −0.05 / -0.172
| −0.14 / -0.16 | 0.22 / 0.45 | 0.29 / 0.50 | |
Sleep duration (min/night) | 0.06 / 0.05 | −0.14 / -0.15 | −0.13 / -0.15 | −0.15 / -0.18 | 0.02 / -0.05 |