# Reliability of Critical Fitness Tests for Police Officers
## 4 Discussion  
The fitness attributes most evaluated in POs and other tactical populations are muscular strength and aerobic capacity [4; 5], as well as the muscular power of the lower limbs [4] and abdominal muscular endurance [5]. In the Portuguese Police Academy (the Higher Institute of Police Sciences and Internal Security), fitness assessments are most used in admission courses, including lower limb muscle power, abdominal muscular endurance, and aerobic capacity. In other words, both in the literature and in the Portuguese Police Academy admission courses, it is clear which are the four most critical fitness attributes when evaluating POs or POs candidates. These attributes were considered when creating the fitness assessment protocol for POs. When choosing the fitness tests that evaluate these attributes, the criteria used included the fitness tests (i) most used in the literature, (ii) most used by the national police, and that which are (iii) easy to apply and require little material. The choice of fitness tests was considered the most used in the literature and the most used in the PSP. This combination resulted in selecting the HG, HJ, 60 s of sit-ups, and the 20 m shuttle run tests. The HJ and 60 s sit-up tests are the most used in the literature and the PSP. The HG test and the 20 m shuttle run also appear as options for the most widely used tests in the literature, and in the PSP, they are used by the Portuguese Police Academy. According to [PERSON] et al. [18], the HG test is one of the main tests used due to its easy accessibility and correlation with the performance of the upper limbs. The execution order of the fitness tests aimed to comply with the progressive increase in fatigue principles. Therefore, (i) the 20 m shuttle run test is the one that accumulates the most fatigue and is the last test; (ii) the 60 s sit-up test was then positioned for the penultimate test; (iii) the lower limb muscle power test (assessed through HJ) was chosen as the first, as it requires an adequate warm-up to avoid any injury and, thus, was the closest test to this preparatory phase; and (iv) handgrip strength was the second test, as the effort expended was around three seconds. The literature does not agree with the standard ICC values for determining acceptable reliability [12]. However, according to [PERSON] et al. [19], the reliability of a protocol is acceptable when the ICC \(>\) 0.85. In our study, the ICC of the variables resulting from the four fitness tests (HG sum, HJ, 60 s of sit-ups, and 20 m shuttle run) is 0.89. According to [PERSON] et al. [19], it has acceptable reliability, and the seven variables presented in Table 2 also have an ICC of 0.89. \begin{table}
\begin{tabular}{l c c c c c} \hline  & **Female** & **Male** & & & \\  & **(n = 30)** & **(n = 92)** & & & \\ \cline{2-6}  & **Mean Rank** & **Mean Rank** & **\(\mathbf{U}\)** & **\(\mathbf{W}\)** & **\(\mathbf{p}\)-Value** \\ \hline HG left (kg) & 18.67 & 75.47 & 2665.000 & 6943.000 & \textless{}0.001 \\ HG right (kg) & 18.90 & 75.39 & 2658.000 & 6936.000 & \textless{}0.001 \\ HG sum (kg) & 17.73 & 75.77 & 2693.000 & 6971.000 & \textless{}0.001 \\ HJ (m) & 17.60 & 75.82 & 2697.000 & 6975.000 & \textless{}0.001 \\
60 s of sit-ups (repetitions) & 49.85 & 65.30 & 1729.500 & 6007.500 & 0.037 \\
20 m shuttle run (shuttles) & 32.68 & 70.90 & 2244.500 & 6522.500 & \textless{}0.001 \\ VO\({}_{2}\)max (mL/kg/min) & 32.53 & 70.95 & 2249.000 & 6527.000 & \textless{}0.001 \\ \hline \end{tabular} Key: HG, handgrip strength; HJ, horizontal jump; T1, moment 1; VO\({}_{2}\)max, aerobic capacity.  
\end{table} 
Table 4: Effect of sex on the fitness performance (T1) of police academy cadets. Another measurement scale used to interpret the ICC is that of [PERSON] et al. [20], which indicates that an ICC between 0.70 and 0.89 is considered highly reliable. Our study showed an ICC of 0.89, which falls within this high-reliability range.