Table 3. Changes in strength and sprint measures from pre- to post-intervention (mean ± SD). Variables Pre Post Hedge's g (95% CI) Changes Significant 20-m sprint (sec)        P-SSIT 3.41 ± 0.26 3.24 ± 0.24 -0.65 (-1.55 to 0.25) Moderate ↓ 0.001        NP-SST 3.45 ± 0.23 3.25 ± 0.19 -0.91 (-1.83 to 0.01) Moderate ↓ 0.007        CON 3.48 ± 0.18 3.48 ± 0.19 ↔ 1.000 Post-test comparisons PSSIT vs. CON -1.06 (-2.00 to -0.13) Moderate ↓ 0.048 NP-SSIT vs. CON -1.16 (-2.11 to -0.21) Moderate ↓ 0.050 P-SSIT vs. NP-SSIT -0.04 (-0.92 to 0.83) Trivial ↔ 1.000 4x9-m shuttle run sec)        P-SSIT 9.49 ± 0.50 9.20 ± 0.54 -0.53 (-1.43 to 0.36) Small ↓ 0.002        NP-SST 9.47 ± 0.51 9.22 ± 0.53 -0.46 (-1.35 to 0.43) Small ↓ 0.001        CON 9.51 ± 0.50 9.51 ± 0.46 ↔ 1.000 Post-test comparisons PSSIT vs. CON -0.59 (-1.49 to 0.30) Small ↓ 0.001 NP-SSIT vs. CON -0.56 (-1.45 to 0.33) Small ↓ 0.001 P-SSIT vs. NP-SSIT -0.04 (-0.91 to 0.84) Trivial ↔ 1.000 Maximal strength (kg)        P-SSIT 236.5 ± 66.3 248.5 ± 64.2 0.18 (-0.70 to 1.05) Trivial ↑ 0.001        NP-SST 233.0 ± 58.8 240.5 ± 54.7 0.13 (-0.75 to 1.00) Trivial ↑ 0.045        CON 229.0 ± 59.6 230.5 ± 60.3 ↔ 1.000 Post-test comparisons PSSIT vs. CON 0.28 (-0.61 to 1.16) Small ↑ 0.007 NP-SSIT vs. CON 0.17 (-0.71 to 1.04) Trivial ↑ 0.031 P-SSIT vs. NP-SSIT 0.13 (-0.75 to 1.00) Trivial ↔ 1.000 P-SSIT: programming volume-loads including progressive; NP-SSIT: nonprogressive; CON: control.