Table 1.
Participant characteristics, body composition and fat distribution, pulmonary function, and oxygen cost of breathing data presented as mean ± SD.
| Without obesity | With obesity | p-value | |
|---|---|---|---|
| N | 8 | 9 | |
| Sex (M/F) | 3/5 | 6/3 | 0.229 |
| Tanner stage (1/2/3/4/5) a | 2/4/1/0/1 | 1/3/5/0/0 | 0.251 |
| Age (year) | 10.8 ± 0.6 | 11.2 ± 0.6 | 0.1986 |
| Height (cm) | 143.4 ± 5.8 | 148.6 ± 7.5 | 0.1345 |
| BM (kg) | 36.3 ± 4.2 | 64.1 ± 15.0 | 0.0001 |
| BMI (kg·m−2) | 17.6 ± 1.5 | 28.6 ± 4.2 | <0.0001 |
| BMI Z-score b | 0.11 ± 0.69 | 2.12 ± 0.32 | <0.0001 |
| BMI percentile (CDC) | 54.2 ± 24.7 | 97.9 ± 1.4 | <0.0001 |
| BMI % of the 95th percentile | 75.5 ± 7.1 | 121.1 ± 18.0 | <0.0001 |
| Body surface area (m2) | 1.2 ± 0.1 | 1.6 ± 0.2 | 0.0185 |
| Fat (%) | 27.6 ± 6.1 | 45.9 ± 2.8 | <0.0001 |
| Lean BM (kg) | 26.2 ± 3.7 | 34.6 ± 7.6 | 0.0135 |
| Chest mass (kg) | 5.9 ± 1.4 | 10.4 ± 2.9 | 0.0012 |
| Abdomen mass (kg) | 8.9 ± 1.7 | 18.1 ± 4.6 | 0.0002 |
| Pulmonary function | |||
| FVC (L) | 2.61 ± 0.36 | 2.97 ± 0.49 | 0.1101 |
| FVC (% predicted) | 103.4 ± 10.1 | 107.2 ± 7.9 | 0.3930 |
| FEV1 (L) | 2.32 ± 0.23 | 2.48 ± 0.5 | 0.5056 |
| FEV1 (% predicted) | 104.4 ± 7.2 | 103.6 ± 10 | 0.8509 |
| FEV1/FVC | 89.1 ± 4.8 | 83.7 ± 3.7 | 0.0181 |
| PEF (L/s) | 5.02 ± 0.40 | 4.65 ± 0.45 | 0.0952 |
| PEF (% predicted) | 106.4 ± 7.6 | 91.9 ± 8.0 | 0.0017 |
| MVV (L·min−1) | 85.1 ± 8.4 | 84.4 ± 9.0 | 0.8746 |
| MVV (% predicted) | 102.4 ± 12.2 | 94.2 ± 9.8 | 0.1480 |
| TLC (L) | 3.24 ± 0.42 | 3.55 ± 0.59 | 0.2398 |
| TLC (% predicted) | 95.9 ± 7.8 | 97.4 ± 8.4 | 0.6967 |
| FRC (L) | 1.41 ± 0.27 | 1.18 ± 0.21 | 0.0634 |
| FRC (%TLC) | 43.4 ± 7.2 | 33.5 ± 5.7 | 0.0061 |
| ERV (L) | 0.66 ± 0.13 | 0.49 ± 0.18 | 0.0479 |
| ERV (% predicted) | 69.9 ± 13.5 | 51.9 ± 22.3 | 0.0665 |
| RV (L) | 0.60 ± 0.15 | 0.54 ± 0.16 | 0.4554 |
| RV (% predicted) | 82.5 ± 18.6 | 68.8 ± 18.80 | 0.1514 |
| IC (L) | 1.84 ± 0.33 | 2.37 ± 0.50 | 0.0213 |
| IC (% predicted) | 103.4 ± 15.7 | 126.5 ± 13.1 | 0.0048 |
| Oxygen cost of breathing c | |||
| Slope V̇O2 / V̇E (mL/L) | 2.09 ± 0.46 | 2.08 ± 0.64 | 0.9900 |
| Y intercept (mL) | 183 ± 15 | 229 ± 42 | 0.0124 |
| R2 | 0.97 ± 0.05 | 0.98 ± 0.04 | 0.6116 |
BM: body mass; BMI: body mass index; CDC: Centers for Disease Control and Prevention; FVC: forced vital capacity; FEV1: forced expiratory volume in 1s; PEF: peak expiratory flow; MVV: maximal voluntary ventilation; TLC: total lung capacity; FRC: functional residual capacity; ERV: expiratory reserve volume; RV: residual volume; IC: inspiratory capacity.
Tanner stage for one child was not recorded
Z-score expresses BMI as the number of standard deviations above or below the CDC reference mean
O2 cost of breathing data for two children without obesity were excluded because R2 for relationship between V̇O2 and V̇E was below 0.80.