Table 3.

Muscle cross-sectional area and counter-movement jump parameters separated by group, and main effect of group.

Variable	Group values			Intercept			Athlete								Age				Mass				Full model
	C	S	T				Main effect		Contrastsa						Main effect				Main effect				p	Adjusted R2
									T versus Sb			T versus Cb
				b	SE	p	p	η2p	b	SE	p	b	SE	p	b	SE	p	η2p	b	SE	p	η2p
MuscA (mm2)	8990 (1078)	9399 (1337)	9534 (999)	4472	1135	***	*	0.12	−100	329	1.00	−689	318	0.07					66	14	***	0.34	***	0.36
PMax (kW/kg)	2.82 (0.71)	3.44 (1.32)	3.00 (0.78)	4.41	0.81	***	*	0.21	0.53	0.21	*	−0.12	0.20	>0.99	−0.06	0.01	***	0.65	0.03	0.01	**	0.18	***	0.66
PMaxRel (W/kg)	37.4 (11.1)	45.6 (15.8)	38.2 (9.5)	105.0	10.1	***	**	0.21	6.7	2.6	*	−1.20	2.50	>0.99	−0.7	0.1	***	0.67	−0.3	0.1	*	0.12	***	0.69
FMax (kN)	1.82 (0.32)	1.96 (0.44)	1.84 (0.4)	1.18	0.37	***									−0.01	0.00	***	0.33	0.02	0.00	***	0.35	***	0.48
FMaxRel (N/kg)	23.8 (3.9)	25.9 (4.2)	23.5 (4.4)	35.96	2.49	***									−0.19	0.04	***	0.34					***	0.32
HMax (m)	0.34 (0.1)	0.40 (0.15)	0.32 (0.10)	0.67	0.06	***	*	0.17	0.08	0.03	*	0.02	0.03	>0.99	−0.01	0.00	***	0.47					***	0.49

Although training years were initially included as a factor, it was not found to be significant for any variable; hence, it is not shown.

*p < 0.05.

**p < 0.01.

***p < 0.001.

b = model coefficient; C = control; η²_p = partial eta-squared; MuscA = calf muscle cross-sectional area; S = sprinter; SE = standard error of the coefficient; T = tennis.

^aPositive model coefficients represent greater values in tennis players.

^bBonferroni correction was applied due to multiple comparisons.