Strength Level of Professional Elite Soccer Players after the COVID-19 Lockdown Period: A Retrospective Double-Arm Cohort Study

Table 3

Team B strength values before (pre) and after (post) quarantine period.

	Pre		Post		Mean Difference		95% CI		†	d‡
Knee extensors	M	±SD	M	±SD	M	±SD
Concentric peak torque	241.91	46.05	238.29	47.35	3.62	67.03	−24.68	31.93	0.79	NA
Eccentric peak torque	294.29	61.55	293.04	44.11	1.25	74.17	−30.07	32.57	0.93	NA
Knee flexors
Concentric peak torque	148.75	24.91	144.75	24.34	4.00	34.77	−10.68	18.68	0.57	NA
Eccentric peak torque	294.37	61.60	185.75	27.10	108.62	72.72	77.91	139.33	<0.01	2.31
HQ ratios
Conventional	0.61	0.12	0.61	0.05	−0.01	0.03	−7.23	15.44	0.81	NA
Functional	1.22	0.36	0.78	0.10	−0.44	0.01	11.27	21.48	<0.01	3.44

Mean (M); standard deviation (SD); confidence interval of 95% (CI); not applicable (NA); ^∗difference statistically significant ( < 0.05); † alfa level  < 0.05; and ‡ cohen d effect size. Bold measures showed statistical significancy.