The Main and Interactive Effects of Biological Maturity and Relative Age on Physical Performance in Elite Youth Soccer Players
Table 1
Descriptive statistics of participants per age group.
Variables
U12 (n= 24)
U13 (n= 19)
U14 (n= 21)
U15 (n= 8)
U16 (n= 12)
SD
SD
SD
SD
SD
Chronological age
11.75
0.29
12.73
0.34
13.63
0.25
14.68
0.38
15.67
0.38
Height (cm)
150.20
6.40
160.70
8.69
162.20
8.30
175.20
6.70
176.40
6.74
Weight (kg)
39.2
4.30
45.90
8.10
48.10
6.20
63.10
8.30
63.50
7.20
Predicted adult height (cm)
182.4
5.30
185.7
6.3
180.5
7.1
183.5
2.7
182.2
4.9
Relative age
0.68
0.28
0.67
0.31
0.69
0.25
0.76
0.23
0.58
0.38
Maturity z-score
−0.07
0.80
0.33
0.82
0.01
0.46
0.42
0.51
0.20
0.50
5 m sprint (s)
1.15
0.05
1.12
0.06
1.08
0.06
1.08
0.08
1.06
0.05
20 m sprint (s)
3.51
0.13
3.28
0.37
3.25
0.12
3.12
0.14
3.14
0.21
Change of direction (s)
2.58
0.14
2.36
0.07
2.27
0.09
2.24
0.06
2.21
0.13
CMJ (cm)
24.97
3.56
27.10
4.68
31.60
4.50
36.60
5.70
32.90
4.50
RSI
2.00
0.40
1.73
0.27
2.07
0.31
2.43
0.27
2.49
0.37
Note. is mean, and SD is standard deviation. Relative age was calculated as the difference between the participant’s birthdate and the cutoff date (31st August). This was then divided by the number of days within the year (365 days).
