Table 2.
Body composition and bioimpedance patterns: development trajectories of the soccer players according to chronological decimal age (years).
| Breakpoints in Development (Years) | Rate of Player Development | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable | Breakpoint 1. (95% CI) | Breakpoint 2. (95% CI) | Slope 1 (95% CI) | p-Value | Slope 2 (95% CI) | p-Value | Slope 3 (95% CI) | p-Value | r2 |
| FFM | 11.7 (11.1; 12.3) | 15.1 (14.5; 15.7) | 2.1 (−0.4; 4.7) | 0.056 | 7.6 (6.7; 8.5) | <0.001 | 0.1 (−1.7; 1.8) | 0.48 | 0.84 |
| TBW | 13.4 (12.9; 13.9) | 14.2 (13.8; 14.6) | 2.1 (1.3; 2.8) | <0.001 | 12.7 (5.0; 20.4) | 0.01 | 1.4 (0.8; 2.0) | <0.001 | 0.84 |
| BCM | 13.6 (13.2; 14.0) | 14.1 (13.8; 14.4) | 0.7 (0.2; 1.1) | <0.001 | 14.1 (3.6; 24.6) | <0.01 | 1.2 (0.8; 1.6) | <0.001 | 0.83 |
| UMA | 12.9 (12.2; 13.5) | 15.1 (14.4; 15.8) | 2.2 (0.9; 3.6) | <0.001 | 7.9 (6.0; 9.8) | <0.001 | −0.8 (−2.8; 1.2) | 0.22 | 0.72 |
| CMA | 15.4 (14.6; 16.2) | - | 7.6 (6.5; 8.8) | <0.001 | −3.7 (−8.0; 0.5) | 0.04 | - | - | 0.53 |
| TMA | 13.5 (12.7; 14.2) | 14.5 (13.6; 15.3) | 10.1 (5.8; 14.4) | <0.001 | 43.3 (4.9; 81.6) | 0.01 | 3.5 (0.1; 7.0) | 0.02 | 0.72 |
| VL/H | 12.8 (12.1; 13.5) | 14.3 (13.9; 14.7) | −19.4 (−29.5; −9.3) | <0.001 | −76.7 (−103.5; −49.9) | <0.001 | −9.0 (−15.6; −2.5) | <0.01 | 0.79 |
| PA | 12.7 (11.9; 13.4) | 16.9 (16.3; 17.5) | −0.1 (−0.2; 0.2) | 0.48 | 0.4 (0.3; 0.5) | <0.001 | −0.4 (−0.8; 0.0) | 0.055 | 0.58 |
Note: CI = confidence interval; FFM = fat free mass; TBW = total body water, BCM = body cell mass; UMA = upper arm muscle area; CMA = calf muscle area; TMA = thigh muscle area; PA = phase angle; VL/H = vector length standardized for height; statistical significance set at p < 0.05.