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Table 1 Demographics, anthropometrics, athletic performance scores, dietary intakes and biomarkers of iron status

From: Sex-specific relationships among iron status biomarkers, athletic performance, maturity, and dietary intakes in pre-adolescent and adolescent athletes

  Composite (n = 249) Males (n = 179) Females (n = 70) Outliers (n = 16)
Age (y) 12.0 ± 2.1 (n = 249) 12.0 ± 2.1 (n = 179) 12.0 ± 2.2 (n = 70)  
Maturity Offset (y) −1.3 ± 1.9 (n = 249) −1.7 ± 1.7 (n = 179)* −0.1 ± 1.8 (n = 70)  
Height (cm) 155.2 ± 13.6 (n = 249) 156.3 ± 13.9 (n = 179)* 152.4 ± 12.3 (n = 70)  
Weight (kg) 48.0 ± 16.0 (n = 249) 49.1 ± 16.5 (n = 179) 45.3 ± 14.5 (n = 70) 120.6 kg
Body Fat (%) 20.2 ± 6.5 (n = 244) 19.7 ± 6.7 (n = 175) 21.5 ± 5.9 (n = 69) 47.9%
Arm eCSA (cm2) 14.3 ± 6.9 (n = 246) 15.6 ± 7.3 (n = 176)* 11.2 ± 4.6 (n = 70) 45.74 cm2
Thigh eCSA (cm2) 80.6 ± 31.5 (n = 245) 83.3 ± 33.0 (n = 175)* 73.7 ± 26.3 (n = 70)  
Vertical Jump (cm) 40.2 ± 9.4 (n = 246) 41.7 ± 9.6 (n = 177)* 36.4 ± 7.4 (n = 69)  
Broad Jump (cm) 168.6 ± 30.2 (n = 247) 172.9 ± 30.6 (n = 178)* 157.3 ± 26.2 (n = 69)  
Pro-Agility (s) 5.8 ± 0.6 (n = 247) 5.7 ± 0.6 (n = 177)* 5.9 ± 0.5 (n = 70) 8.76 s
L Cone (s) 9.4 ± 0.9 (n = 245) 9.3 ± 1.0 (n = 176)* 9.7 ± 0.8 (n = 69) 15.0 s
20 Yard Dash (s) 3.7 ± 0.5 (n = 248) 3.7 ± 0.5 (n = 178)a 3.8 ± 0.4 (n = 70) 5.98, 6.79 s
Power Push Up (N) 170.6 ± 84.1 (n = 246) 185.5 ± 90.0 (n = 177)* 132.6 ± 51.3 (n = 69) 583, 601 N
Energy Intake (kcals·d− 1) 2052 ± 711 (n = 97) 2158 ± 749 (n = 66)* 1827 ± 568 (n = 31)  
Carbohydrates (g·d− 1) 244 ± 89 (n = 97) 256 ± 89 (n = 66)* 217 ± 83 (n = 31)  
Protein (g·d− 1) 90 ± 38 (n = 97) 98 ± 41 (n = 66)* 74 ± 25 (n = 31)  
Fat (g·d−1) 82 ± 37 (n = 97) 84 ± 39 (n = 66) 76 ± 34 (n = 31)  
Iron (mg·d− 1) 16.5 ± 9.7 (n = 97) 17.9 ± 10.9 (n = 66)*b 13.5 ± 5.5 (n = 31) 46.0, 44.8, 55.0, 62.0 mg·d− 1
Hemoglobin (g·L− 1) 113 ± 16 (n = 128) 114 ± 16 (n = 100) 112 ± 19 (n = 28)  
Ferritin (μg·L− 1) 24.0 ± 15.0 (n = 118) 25.3 ± 16.2 (n = 94)* 18.6 ± 7.3 (n = 24)  
sTfR (nmol·L− 1) 22.1 ± 6.4 (n = 105) 21.9 ± 6.8 (n = 76) 22.8 ± 5.5 (n = 29) 38.8, 44.5, 66.7 nmol·L− 1
  1. Values are means ± standard deviations (SD)
  2. *Indicates a significant difference between the mean values of males versus females (p ≤ 0.05) with outliers included
  3. aIndicates a significant difference after removal of outliers. bIndicates difference became non-significant after removal of outliers