Table 3.
The relationship between measures of body mass index and body composition and frequency of sports participation
| Variable | BMI z-score percentile categories | ln(FMI) z-score percentile categories | FFMI z-score percentile categories | |||
|---|---|---|---|---|---|---|
| Wald Chi-Squared = 77.92; p < .001 | Wald Chi-Squared = 85.47; p < .001 | Wald Chi-Squared = 85.47; p < .001 | ||||
| Level 1 | O.R. [95% C.I.] | p-value | O.R. [95% C.I.] | p-value | O.R. [95% C.I.] | p-value |
| Sports Frequency (reference: daily) | ||||||
| Never | 2.222 [0.977–5.052] | .057 | 2.485 [0.961–6.429] | .060 | 1.816 [0.619–5.328] | .277 |
| Less than weekly | 0.435 [0.236–0.802] | .008** | 0.466 [0.210–1.341] | .061 | 0.455 [0.214–0.969] | .041** |
| Weekly | 0.970 [0.750–1.256] | .819 | 0.967 [0.697–1.341] | .841 | 0.945 [0.676–1.321] | .741 |
| Most days | 0.911 [0.707–1.174] | .471 | 0.998 [0.728–1.369] | .990 | 0.832 [0.596–1.162] | .281 |
| Sex (reference: female) | ||||||
| Male | 0.843 [0.687–1.035] | .102 | 0.975 [0.754–1.261] | .846 | 1.063 [0.815–1.386] | .654 |
| Age at test | 1.110 [1.041–1.183] | .001** | 1.005 [0.928–1.089] | .903 | 1.030 [0.947–1.120] | .486 |
| Ethnicity (reference: white/other) | ||||||
| Black | 1.563 [1.183–2.066] | .002** | 1.809 [1.268–2.580] | .001** | 1.612 [1.130–2.300] | .008** |
| South Asian | 0.607 [0.452–0.815] | .001** | 1.306 [0.920–1.854] | .136 | 0.253 [0.157–0.408] | <.001*** |
| Family Affluence Scale (reference: low) | ||||||
| Moderate | 1.209 [0.816–1.792] | .344 | 1.344 [0.818–2.209] | .244 | 1.491 [0.892–2.492] | .127 |
| High | 1.107 [0.692–1.771] | .671 | 1.728 [0.959–3.112] | .069 | 1.940 [1.052–3.574] | .034* |
| Free school lunches (reference: no) | ||||||
| Yes | 1.426 [1.087–1.870] | .010* | 1.681 [1.211–2.334] | .002** | 1.582 [1.114–2.247] | .010* |
| Cars owned (reference: 0) | ||||||
| 1 | 0.988 [0.749–1.305] | .934 | 1.040 [0.737–1.466] | .824 | 0.987 [0.690–1.411] | .941 |
| 2 | 1.052 [0.731–1.513] | .787 | 0.872 [0.550–1.381] | .559 | 0.674 [0.414–1.097] | .113 |
| Multiple Deprivation Index (reference: low) | ||||||
| Intermediate | 1.275 [0.914–1.780] | .153 | 1.116 [0.735–1.696] | .607 | 1.318 [0.846–2.053] | .222 |
| High | 1.385 [0.979–1.960] | .066 | 1.384 [0.910–2.103] | .129 | 1.314 [0.828–2.085] | .246 |
| Level 2: Variance on School Level | 0.053 [0.012–0.227] | 0.048 [0.008–0.298] | 0.112 [0.026–0.479] | |||
O.R. Odds Ratio, C.I. Confidence Interval, BMI Body Mass Index, FMI Fat Mass Index, FFMI Fat-Free Mass Index
*: p < .05; **: p < .01; ***: p < .001
Significant associations (p < .05) on the first level of the multilevel model are in bold