Table 1
Descriptive statistics.
| Variables | Boys (n = 949) | Girls (n = 1007) |
|---|---|---|
| Age, years M (SD) | 15.8 (0.3) | 15.8 (0.3) |
| Height, cm M (SD) | 175.9 (7.6) | 165.3 (6.1) |
| Weight, kg M (SD) | 67.5 (12.5) | 58.2 (10.1) |
| Body mass index, kg/m² M (SD) | 21.7 (3.4) | 26.8 (5.8) |
| Weight statusa | ||
| underweight % | 6.8 | 9.2 |
| normal weight % | 75.2 | 77.0 |
| overweight % | 13.9 | 11.6 |
| obese % | 4.1 | 2.3 |
| Self-esteem scale RSES, M (SD) | 29.6 (5.6) | 26.8 (5.8) |
| Body-Esteem Scale for Adolescents and Adults BESAA, M (SD) | 36.8 (7.4) | 31.5 (7.8) |
| Maturationb | ||
| yes % | 94.6 | 98.5 |
| no % | 5.4 | 1.5 |
| Ethnic backgroundc | ||
| Finland % | 96.2 | 97.0 |
| other than Finland % | 3.8 | 3.0 |
| Physically active days/weekd | ||
| low active 0–2 days/week % | 18.1 | 22.1 |
| light active 3–4 days/week % | 33.4 | 36.5 |
| active 5–6 days/week % | 26.9 | 27.9 |
| very active 7 days/week % | 21.6 | 13.4 |
| Family Wealthe | ||
| below average % | 8.0 | 10.6 |
| average % | 26.3 | 30.8 |
| good % | 65.7 | 58.5 |
[i] Note. M means; SD standard deviation.
a Weight status by international (IOTF) gender- and age-specific body mass index cut-offs for thinness, overweight, and obesity.
b Maturation: yes: had had an ejaculation for boys; had begun to menstruate for girls.
c Ethnic background other than Finland: the respondent was born outside Finland, or had one or both parents born outside Finland.
d Physicallly active days/week based on moderate-to-vigorous physical activity (MVPA) ‘Over the past 7 days, on how many days were you physically active for a total of at least 60 minutes per day?’.
e Self-evaluated family wealth based on the question ‘What do you think of your family’s financial situation?’ with responses: My family is doing very well financially/ My family is doing quite well financially/ My family’s financial situation is about average/ My family is not doing very well financially/ My family is doing very poorly financially.
Figure 1
Distribution of body-esteem sum scores for 15-year-old boys.
Figure 2
Distribution of body-esteem sum scores for 15-year-old girls.
Table 2
Associations between physically active days and body-esteem. Mixed effects linear regression.
| Physically active days/week | Boys | Girls | ||||
|---|---|---|---|---|---|---|
| Coefficient | 95% CI | p | Coefficient | 95% CI | p | |
| 0–2 | 1.00 | 1.00 | ||||
| 3–4 | 1.65 | 0.31–2.99 | 0.016 | 1.56 | 0.27–2.85 | 0.018 |
| 5–6 | 2.93 | 1.53–4.33 | <0.001 | 2.63 | 1.27–3.99 | <0.001 |
| 7 | 4.40 | 2.91–5.89 | <0.001 | 2.77 | 1.07–4.46 | 0.001 |
| Model R2 % | 4.32 | 1.72 | ||||
Table 3
Multilevel mixed effects linear regression analysis for the body-esteem of 15-year-old boys.
| Coefficient | 95% CI | p | R2 % | |
|---|---|---|---|---|
| Physically active days/week | 5.0 | |||
| 0–2 | 1.00 | |||
| 3–4 | 0.52 | –0.75–1.78 | 0.425 | |
| 5–6 | 1.83 | 0.52–3.16 | 0.006 | |
| 7 | 2.61 | 1.19–4.02 | <0.001 | |
| Weight status | 5.2 | |||
| normal weight | 1.00 | |||
| thinness | –1.13 | –2.90–0.64 | 0.209 | |
| overweight | –2.60 | –3.82–-1.38 | <0.001 | |
| obese | –6.05 | –8.31–-3.79 | <0.001 | |
| Family wealth | 4.9 | |||
| under the average | 1.00 | |||
| average | 1.80 | 0.08–3.50 | 0.040 | |
| good | 2.65 | 1.07–4.23 | 0.001 | |
| Self-esteem scale | 0.54 | 0.46–0.61 | <0.001 | 20.8 |
| Model R2 % | 26.3 |
[i] Adjusted for maturation state and ethnic background.
Table 4
Multilevel mixed effects linear regression analysis for the body-esteem of 15-year-old girls.
| Coefficient | 95% CI | p | R2 % | |
|---|---|---|---|---|
| Physically active days/week | 1.3 | |||
| 0–2 | 1.00 | |||
| 3–4 | 0.69 | –0.29–1.66 | 0.166 | |
| 5–6 | 0.93 | –0.11–1.97 | 0.079 | |
| 7 | 0.89 | –0.41–2.19 | 0.179 | |
| Weight status | 8.0 | |||
| normal weight | 1.00 | |||
| thinness | 0.94 | –0.33–2.20 | 0.152 | |
| overweight | –4.53 | –5.67–-3.39 | <0.001 | |
| obese | –5.39 | –7.98–-2.80 | <0.001 | |
| Family wealth | 2.2 | |||
| below average | 1.00 | |||
| average | 0.01 | –1.28–1.29 | 0.990 | |
| good | 0.77 | –0.46–2.00 | 0.220 | |
| Self-esteem scale | 0.79 | 0.73–0.85 | <0.001 | 39.2 |
| Model R2 % | 46.8 |
[i] Adjusted for maturation state and ethnic background.