Table 3. Reliability (relative biases and absolute TEs) of the positioning systems for determining the distances covered and sprint mechanical properties.
| Criterion variables§ (section of measurement within the circuit; Fig 1) |
10 Hz GPS | 18 Hz GPS | 20 Hz LPS | |||
|---|---|---|---|---|---|---|
| #1vs.2 (n = 49) | #1vs.2 (n = 43) | #1vs.2 (n = 46) | ||||
| Bias (%)±90% CI | TE (Unit)±90% CI | Bias (%)±90% CI | TE (Unit)±90% CI | Bias (%)±90% CI | TE (Unit)±90% CI | |
| 25.1 m sprinting with CODs (1) | -0.5±1.3 | 0.9±0.1 | -0.8±0.5 | 0.3±0.1 | +0.1±0.2 | 0.2±0.0 |
| 10 m walking with COD (2) | -3.0±2.1 | 0.6±0.1 | -0.3±0.5 | 0.1±0.0 | -0.3±0.6 | 0.2±0.0 |
| 10 m jogging with jump (3) | -2.1±3.2 | 1.0±0.2 | -0.2±0.6 | 0.2±0.0 | -0.1±0.3 | 0.1±0.0 |
| 10 m jogging (4) | -4.1±2.2 | 0.7±0.1 | -2.6±1.6 | 0.4±0.1 | -1.6±1.5 | 0.5±0.1 |
| 10 m walking (5) | -1.4±1.8 | 0.5±0.1 | -1.6±0.8 | 0.2±0.0 | -0.8±1.7 | 0.5±0.1 |
| 5 m sprinting (6) | -1.1±4.1 | 0.5±0.1 | -1.2±1.8 | 0.2±0.0 | +0.4±1.1 | 0.2±0.0 |
| 10 m sprinting (7) | +2.5±3.5 | 0.9±0.2 | -0.6±1.6 | 0.4±0.1 | +0.1±0.7 | 0.2±0.0 |
| 20 m sprinting (8) | +2.2±2.2 | 1.2±0.2 | -0.2±1.1 | 0.5±0.1 | 0.0±0.4 | 0.2±0.0 |
| 30 m sprinting (9) | +1.2±1.3 | 1.1±0.2 | -0.7±0.8 | 0.6±0.1 | 0.0±0.3 | 0.2±0.0 |
| 129.6 m entire circuit (10) | -2.0±0.8 | 3.0±0.5 | -1.1±0.4 | 1.4±0.3 | -0.8±0.4 | 1.7±0.3 |
| 129.6 m entire circuit (10*) | -2.4±0.9 | 3.4±0.6 | -0.9±0.4 | 1.5±0.3 | -0.4±0.4 | 1.4±0.2 |
| 1.1±0.0 s for τ (6–9) | +2.9±7.2 | 0.2±0.0 | +2.7±3.1 | 0.1±0.0 | -0.2±2.8 | 0.1±0.0 |
| 8.2±0.1 m/s for Vmax (6–9) | +1.4±1.1 | 0.3±0.0 | +0.6±1.1 | 0.3±0.0 | -0.4±0.5 | 0.1±0.0 |
| 7.7±0.1 N/kg for Fmax (6–9) | +6.3±6.8 | 1.3±0.2 | -1.0±2.5 | 0.5±0.1 | +1.0±2.5 | 0.6±0.1 |
| 16.1±0.4 W/kg for Pmax (6–9) | +7.0±6.1 | 2.5±0.4 | -0.4±2.6 | 1.0±0.2 | +0.3±2.0 | 1.1±0.2 |
GPS = Global positioning system; LPS = Local positioning system; #1 = Device 1; #2 = Device 2; TE = Typical error; CI = Confidence interval; COD = Change of direction; τ = Acceleration time constant; Vmax = Theoretical maximal running velocity; Fmax = Theoretical maximal horizontal force; Pmax = Theoretical maximal horizontal power output.
§ = The criterion data for the distances covered and sprint mechanical properties are reported as the true distances and overall means±90% CIs across all trials, respectively.
* = Entire distance covered calculated through the summation of the single sections of the circuit (i.e., without the noise during standing; Fig 2).