Table 13. Regression models of the performance in the different physical fitness tests in the 13-years-old group.

Age group	Variable	Analysis	R2	p value	Included independent variables	SC	Equation
13 years old	Long jump	Model 1	0.47	0.005	Sitting height	0.69	Long jump = −1.390 + 0.038*sitting height
				Model 2	0.74	<0.001	Sitting height	0.99	Long jump = − 0.550 + 0.055*sitting height − 0.075*corrected leg girth
							Corrected leg girth	−0.60
				Model 3	0.82	<0.001	Sitting height	0.82	Long jump = −0.356 + 0.045*sitting height − 0.085*corrected leg girth + 0.190*bi-styloid breath
											Corrected leg girth	−0.69
			Bi-styloid breath				0.38
		Medicine ball throw	Model 1	0.63	<0.001	Maturity offset	0.79	Medicine ball throw = 5.332 + 1.544*maturity offset
		CMJ	Model 1	0.35	0.020	∑8 skinfolds	−0.59	CMJ = 33.668 − 0.076*Sum of 8 skinfolds
		CMJ power	Model 1	0.73	<0.001	Body mass	0.85	CMJ power = 124.236 + 9.072*body mass
				Model 2	0.83	<0.001	Body mass	1.48	CMJ power = 395.396 + 15.715*body mass − 30.141*corrected arm girth
							Corrected arm girth	−0.70
				Model 3	0.89	<0.001	Body mass	2.00	CMJ power = −541.713 + 21.252*body mass − 42.547*corrected arm girth + 23.420*muscle mass (%)
											Corrected arm girth	−0.98
			Muscle mass (%)				0.39
		20 m sprint	Model 1	0.42	0.009	Muscle-bone index	0.65	Sprint = 2.806 + 0.561*muscle-bone index
	Agility test	Model 1	0.31	0.032	Bi-styloid breath	−0.55	Agility = 14.275 − 0.982*bi-styloid breadth

Notes.

SC

Standardized coefficients