Table 2. Validity (relative biases and absolute TEEs) 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 | |||
|---|---|---|---|---|---|---|
| #1&2 (n = 108) | #1&2 (n = 96) | #1&2 (n = 101) | ||||
| Bias (%)±90% CI | TEE (Unit)±90% CI | Bias (%)±90% CI | TEE (Unit)±90% CI | Bias (%)±90% CI | TEE (Unit)±90% CI | |
| 25.1 m sprinting with CODs (1) | -11.7±0.7 | 1.0±0.1 | -9.2±0.3 | 0.5±0.1 | -2.1±0.3 | 0.4±0.1 |
| 10 m walking with COD (2) | -5.0±1.2 | 0.7±0.1 | -1.9±0.3 | 0.2±0.0 | +6.1±0.4 | 0.2±0.0 |
| 10 m jogging with jump (3) | +1.9±1.7 | 1.0±0.1 | +1.8±0.4 | 0.3±0.0 | +4.2±0.3 | 0.2±0.0 |
| 10 m jogging (4) | -3.3±1.2 | 0.7±0.1 | -6.1±1.0 | 0.5±0.1 | +5.7±1.0 | 0.6±0.1 |
| 10 m walking (5) | -5.5±1.0 | 0.6±0.1 | -2.2±0.5 | 0.3±0.0 | +8.4±1.0 | 0.6±0.1 |
| 5 m sprinting (6) | -13.0±1.6 | 0.5±0.1 | -11.8±1.1 | 0.3±0.0 | -1.6±0.7 | 0.2±0.0 |
| 10 m sprinting (7) | -11.9±1.3 | 0.8±0.1 | -10.6±0.9 | 0.5±0.1 | +1.3±0.5 | 0.3±0.0 |
| 20 m sprinting (8) | -8.9±0.9 | 1.1±0.1 | -8.8±1.0 | 1.0±0.1 | +2.0±0.3 | 0.4±0.0 |
| 30 m sprinting (9) | -6.8±0.6 | 1.1±0.1 | -6.7±0.6 | 1.0±0.1 | +1.5±0.2 | 0.3±0.0 |
| 129.6 m entire circuit (10) | -2.1±0.4 | 3.6±0.4 | -1.6±0.3 | 1.9±0.2 | +6.2±0.2 | 1.9±0.2 |
| 129.6 m entire circuit (10*) | -4.7±0.5 | 4.2±0.5 | -4.5±0.3 | 1.9±0.2 | +1.9±0.2 | 1.6±0.2 |
| 1.1±0.0 s for τ (6–9) | +24.7±4.1 | 0.2±0.0 | +25.4±3.1 | 0.2±0.0 | -10.0±1.5 | 0.1±0.0 |
| 8.2±0.1 m/s for Vmax (6–9) | 0.0±0.6 | 0.3±0.0 | -0.2±0.7 | 0.4±0.0 | +2.1±0.3 | 0.2±0.0 |
| 7.7±0.1 N/kg for Fmax (6–9) | -16.6±2.5 | 1.3±0.2 | -17.0±1.7 | 0.9±0.1 | +15.1±1.6 | 0.7±0.1 |
| 16.1±0.4 W/kg for Pmax (6–9) | -16.3±2.3 | 2.5±0.3 | -16.9±1.5 | 1.5±0.2 | +17.7±1.3 | 1.3±0.1 |
GPS = Global positioning system; LPS = Local positioning system; #1 = Device 1; #2 = Device 2; TEE = Typical error of estimate; 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).