Journal of Sports Science and Medicine

Outcome

Variable

Coef.

Std. Err.

P>|z|

[95% Conf. Interval]

5 m Sprint

Age/Maturation

.0421

.0215

1.96

0.050

.0000, .0842

Playing Standard

.0312

.0458

0.68

0.496

-.0585, .1209

Season Phase

-.0104

.0321

-0.32

0.746

-.0733, .0525

Baseline Ability

.1105

.0542

2.04

0.041

.0043, .2167

20 m Sprint

Age/Maturation

.0235

.0184

1.28

0.201

-.0126, .0596

Playing Standard

.1311

.1308

1.00

0.316

-.1253, .3875

Season Phase

.0452

.0512

0.88

0.379

-.0551, .1455

Baseline Ability

.0984

.0423

2.33

0.020

.0155, .1813

30 m Sprint

Age/Maturation

.0156

.0245

0.64

0.524

-.0324, .0636

Playing Standard

.0842

.0712

1.18

0.237

-.0553, .2237

Season Phase

-.1204

.0654

-1.84

0.066

-.2486, .0078

Baseline Ability

.2104

.0952

2.21

0.027

.0238, .3970

40 m Sprint

Age/Maturation

.0087

.0312

0.28

0.780

-.0524, .0698

Playing Standard

.0543

.0821

0.66

0.509

-.1066, .2152

Season Phase

.1842

.0912

2.02

0.043

.0054, .3630

Baseline Ability

.2511

.1124

2.23

0.026

.0308, .4714

Squat Jump (SJ)

Age/Maturation

1.4210

.6532

2.18

0.029

.1407, 2.7013

Playing Standard

.8542

.9214

0.93

0.352

-.9517, 2.6601

Season Phase

-.4210

.5123

-0.82

0.412

-1.4251, .5831

Baseline Ability

1.1024

.4521

2.44

0.015

.2163, 1.9885

Countermovement Jump (CMJ)

Age/Maturation

1.1245

.4852

2.32

0.020

.1735, 2.0755

Playing Standard

.5210

.8124

0.64

0.522

-1.0713, 2.1133

Season Phase

.2145

.3214

0.67

0.503

-.4154, .8444

Baseline Ability

.9421

.4124

2.28

0.023

.1338, 1.7504

Change of Direction (COD)

Age/Maturation

.0312

.0254

1.23

0.219

-.0186, .0810

Playing Standard

.0842

.0412

2.04

0.041

.0034, .1650

Season Phase

.0102

.0214

0.48

0.631

-.0317, .0521

Baseline Ability

.1204

.0512

2.35

0.019

.0200, .2208

Maximal Strength (1RM)

Age/Maturation

3.2145

1.8421

1.75

0.081

-.3960, 6.8250

Playing Standard

5.2142

2.1052

2.48

0.013

1.0880, 9.3404

Season Phase

1.1024

1.4521

0.76

0.447

-1.7437, 3.9485

Baseline Ability

4.4210

1.9521

2.26

0.024

.5949, 8.2471

This table presents a comprehensive network meta-regression analysis to evaluate potential effect modifiers across eight performance outcomes. Variables including Age/Maturation, Playing Standard, Season Phase, and Baseline Ability were pre-specified to assess their impact on intervention efficacy and ensure the assumption of transitivity. Coefficients (Coef.) represent the change in Mean Difference (MD) per unit change in the modifier, with P-values in bold denoting statistical significance (P < 0.05). The significant influence of Baseline Ability across all outcomes and Age/Maturation in jump tests (SJ and CMJ) confirms their roles as key modifiers, while the lack of significant interaction for Playing Standard and Season Phase in sprint acceleration (5 m-20 m) indicates that the comparative hierarchical rankings remain stable across these participant characteristics. All participant-related modifiers were analyzed in separate univariable network meta-regression models. No multivariable models were fitted. Covariate data were complete for all included studies; therefore, no imputation was required and no studies were excluded because of missing covariate information. Findings should be interpreted cautiously because some outcome networks were sparse.