Physical characteristics, bone health, haematological and endocrine profile based on EA status
| Low EA (rRMR<0.9) Mean±SD n=12 | Optimal EA (rRMR>0.9) Mean±SD n=31 | P value | |
| Physical characteristics | |||
| Age (years)* | 21.0±5.0 | 23.5±5.5 | 0.914† |
| Weight (kg) | 61.7±13.4 | 64.5±12.0 | 0.524‡ |
| Height (cm) | 163.9±9.5 | 166.5±7.9 | 0.368‡ |
| Fat mass (kg) | 16.1±7.1 | 13.9±5.5 | 0.288‡ |
| Percent body fat (%) | 25.7±7.8 | 21.1±6.2 | 0.131‡ |
| RMR (mRMR) (kcal/day) | 1328±201 | 1534±235 | 0.011‡ |
| Predicted RMR (pRMR) (kcal/day) (Cunningham equation) | 1513±228 | 1546±226 | 0.668‡ |
| Bone health | |||
| BMD lumbar (g/cm2) | 1.1±0.2 | 1.2±0.1 | 0.080‡ |
| Z-score lumbar | 0.8±1.5 | 1.4±1.0 | 0.091‡ |
| BMD total hip (g/cm2) | 1.1±1.2 | 1.2±0.2 | 0.263‡ |
| Z-score total hip* | 0.8±2.6 | 1.5±2.0 | 0.626† |
| Low BMD§ (Z-score<−1.0 at any scanned site) | 1 (8.3) | 1 (3.2) | 0.104¶ |
| Normal BMD lumbar§ (Z-score>−1.0 at any scanned site) | 11 (91.7) | 30 (96.8) | |
| Haematological and endocrine profiles | |||
| Ferritin (µg/L) | 85.1±81.7 | 115.0±64.9 | 0.042‡ |
| Free triiodothyronine (fT3) (pmol/L)* | 2.6±1.3 | 3.9±0.9 | 0.006† |
| Luteinising hormone (LH) (IU/L) | 2.5±1.7 | 3.5±1.8 | 0.012‡ |
| Follicle-stimulating hormone (FSH) (IU/L) | 2.9±2.1 | 4.1±2.7 | 0.050‡ |
| Estradiol (pmol/L)* | 88.0±0.0 | 237.0±207.0 | <0.001† |
| Testosterone (nmol/L) | 13.6±13.1 | 20.0±5.0 | 0.039‡ |
| Low ferritin level§ | 3 (25.0) | – | 0.004¶ |
| Normal ferritin level§ | 9 (75.0) | 31 (100) | |
| Low fT3 level§ | 8 (66.7) | – | <0.001¶ |
| Normal fT3 level§ | 4 (33.3) | 31 (100) | |
| Low LH level§ | 7 (58.3) | – | <0.001¶ |
| Normal LH level§ | 5 (41.7) | 31 (100) | |
| Low FSH level§ | 7 (58.3) | – | <0.001¶ |
| Normal FSH level§ | 5 (41.7) | 31 (100) | |
| Low estradiol level§ | 7 (87.5) | – | <0.001¶ |
| Normal estradiol level§ | 1 (12.5) | 13 (100) | |
| Low testosterone level§ | 3 (75.0) | – | <0.001¶ |
| Normal testosterone level§ | 1 (25.0) | 18 (100) | |
*Median (IQR).
†Mann-Whitney U test.
‡Independent t-test.
§n (%).
¶x² test.
BMD, bone mineral density; EA, energy availability; RMR, resting metabolic rate.