Table 3.
Validity of the Jump-MVC method for assessment of the force–velocity profile in countermovement jump.
| Mean scores | Intra-class correlation | Within-individual error | Systematic error | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Multiple-point method | Jump-MVC method | ICCs | ICCa | SEM | CV% | t | Sig | ES | |
| MVC Angle 30° | |||||||||
| F0 (N) | 2193.5 ± 379.4 | 3123.3 ± 670.9 | 0.293 (− 0.075–0.673) | 0.450 (− 0.162–0.804) | 290.85 | 10.94 (8.54–15.22) | − 11.30 | 0.000 | 0.84 |
| V0 (m/s) | 4.50 ± 0.83 | 2.98 ± 0.55 | 0.177 (− 0.067–0.520) | 0.300 (− 0.144–0.684) | 0.45 | 12.16 (9.50–16.92) | 11.78 | 0.000 | 0.85 |
| Pmax (W) | 2450.6 ± 554.3 | 2296.1 ± 499.1 | 0.894 (0.599–0.962) | 0.940 (0.749–0.981) | 139.27 | 5.87 (4.58–8.16) | 3.93 | 0.001 | 0.39 |
| F–V slope | − 506.1 ± 137.3 | − 1090.8 ± 336.9 | 0.133 (− 0.069–0.435) | 0.230 (− 0.148–0.606) | 186.58 | − 23.37 (− 18.25 to − 32.51) | 11.08 | 0.000 | 0.84 |
| MVC Angle 60° | |||||||||
| F0 (N) | 2193.5 ± 379.4 | 2831.9 ± 680.8 | 0.361 (− 0.104–0.698) | 0.530 (− 0.232–0.822) | 349.9 | 13.93 (10.87–19.38) | − 6.44 | 0.000 | 0.63 |
| V0 (m/s) | 4.50 ± 0.83 | 3.40 ± 0.97 | 0.319 (− 0.105–0.659) | 0.480 (− 0.234–0.794) | 0.61 | 15.40 (12.024–21.42) | 6.38 | 0.000 | 0.63 |
| Pmax (W) | 2450.6 ± 554.3 | 2329.9 ± 565.9 | 0.911 (0.757–0.964) | 0.950 (0.862–0.982) | 148.3 | 6.20 (4.84–8.63) | 2.88 | 0.008 | 0.26 |
| F–V slope | − 506.1 ± 137.3 | − 913.1 ± 372.2 | 0.180 (− 0.101–0.492) | 0.300 (− 0.226–0.660) | 223.5 | − 31.49 (− 24.59 to − 43.81) | 6.44 | 0.000 | 0.63 |
| MVC Angle 90° | |||||||||
| F0 (N) | 2193.5 ± 379.4 | 2273.04 ± 468.5 | 0.721 (0.468–0.866) | 0.830 (0.638–0.928) | 223.39 | 10.0 (7.81–13.92) | − 1.26 | 0.220 | 0.06 |
| V0 (m/s) | 4.50 ± 0.83 | 4.71 ± 1.92 | 0.426 (0.043–0.700) | 0.590 (0.082–0.823) | 1.13 | 24.48 (19.12–34.06) | − 0.65 | 0.519 | 0.02 |
| Pmax (W) | 2450.6 ± 554.3 | 2591.6 ± 906.1 | 0.762 (0.536–0.887) | 0.860 (0.698–0.940) | 361.25 | 14.33 (11.19–19.93) | − 1.38 | 0.180 | 0.07 |
| F–V slope | − 506.1 ± 137.3 | − 555.9 ± 235.2 | 0.481 (0.125–0.730) | 0.640 (0.222–0.844) | 137.99 | − 25.98 (− 20.29 to − 36.15) | 1.27 | 0.214 | 0.06 |
| MVC Angle: Mean of 30°, 60° and 90° angles | |||||||||
| F0 (N) | 2193.5 ± 379.4 | 2556.4 ± 515.4 | 0.590 (− 0.053–0.848) | 0.740 (− 0.111–0.918) | 214.67 | 9.03 (7.05–12.57) | − 5.97 | 0.000 | 0.60 |
| V0 (m/s) | 4.50 ± 0.83 | 3.74 ± 1.01 | 0.449 (− 0.021–0.739) | 0.620 (− 0.044–0.850) | 0.59 | 14.36 (11.21–19.97) | 4.53 | 0.000 | 0.46 |
| Pmax (W) | 2450.7 ± 554.3 | 2345.0 ± 594.3 | 0.918 (0.797–0.965) | 0.950 (0.887–0.982) | 150.97 | 6.30 (4.92–8.76) | 2.47 | 0.021 | 0.20 |
| F–V slope | − 506.1 ± 137.3 | − 734.2 ± 251.8 | 0.339 (− 0.098–0.671) | 0.500 (− 0.217–0.803) | 136.51 | − 22.01 (− 17.19 to − 30.62) | 5.91 | 0.000 | 0.59 |
F0—maximal isometric force; V0—maximal theoretical velocity; Pmax—maximal power; MVC—maximal voluntary contraction; ICCs—single measures intra-class correlation coefficient; ICCa—average measures intra-class correlation coefficient; SEM—standard error of measurement; CV%—coefficient of variation; ES—Effect size (Cohen’s d); Note that for the two-point methods, the F0 is the actual maximal isometric force (i.e. recorded during maximal voluntary contraction).