Browsing by Author "Mirkov, Dragan M. (6508073239)"

The main objective of present study was to evaluate inter-rater reliability and concurrent validity of Side Hop Test stopwatch vs. force plates timing, and to determine the number of sessions and trials required to minimize the effects of learning on Side Hop Test total time and limb symmetry index. Fifteen healthy male physical education students (mean ± SD: age, 23 ± 3 years; height, 181 ± 9 cm; and weight 72 ± 6 kg) participated. Side Hop Test total time (stopwatch and force plates) of left and right leg, and limb symmetry index (force plates) were obtained over seven sessions conducted 5–7 days apart. Time recordings of two raters were similar (t = −0.56, p > 0.05) with high reliability (all ICC >0.99 and CV% <0.1) and no systematic bias when compared to force plate data (p > 0.05; for rater 1 and 2, respectively). Total time improved across the Sessions (F = 25.87, p < 0.01, ω2 = 0.18) and Trials (F = 68.15, p < 0.01, ω2 = 0.10), with no significant interaction between factors. No between-leg differences were detected (F = 0.52, p > 0.05, ω2 = 0.001). Limb symmetry index ranged from 0.999 to 1.055 across all sessions and trials (all p > 0.05 and ω2 < 0.00). Due to low coefficient of correlation, high interclass correlation coefficient, and the lack in heteroscedasticity, stopwatch measurements are valid to measure total time in the Side Hop Test. Moreover, stopwatch measurements could be reliably used to measure total time in the Side Hop Test, while the test could be administrated with only one experienced rater. Unlike total times, findings on limb symmetry index suggest it could be reliably assessed after seven familiarization sessions. Copyright © 2022 Mirković, Đurić, Sember, Knezevic, Pajek, Mirković and Mirkov.

The main objective of present study was to evaluate inter-rater reliability and concurrent validity of Side Hop Test stopwatch vs. force plates timing, and to determine the number of sessions and trials required to minimize the effects of learning on Side Hop Test total time and limb symmetry index. Fifteen healthy male physical education students (mean ± SD: age, 23 ± 3 years; height, 181 ± 9 cm; and weight 72 ± 6 kg) participated. Side Hop Test total time (stopwatch and force plates) of left and right leg, and limb symmetry index (force plates) were obtained over seven sessions conducted 5–7 days apart. Time recordings of two raters were similar (t = −0.56, p > 0.05) with high reliability (all ICC >0.99 and CV% <0.1) and no systematic bias when compared to force plate data (p > 0.05; for rater 1 and 2, respectively). Total time improved across the Sessions (F = 25.87, p < 0.01, ω2 = 0.18) and Trials (F = 68.15, p < 0.01, ω2 = 0.10), with no significant interaction between factors. No between-leg differences were detected (F = 0.52, p > 0.05, ω2 = 0.001). Limb symmetry index ranged from 0.999 to 1.055 across all sessions and trials (all p > 0.05 and ω2 < 0.00). Due to low coefficient of correlation, high interclass correlation coefficient, and the lack in heteroscedasticity, stopwatch measurements are valid to measure total time in the Side Hop Test. Moreover, stopwatch measurements could be reliably used to measure total time in the Side Hop Test, while the test could be administrated with only one experienced rater. Unlike total times, findings on limb symmetry index suggest it could be reliably assessed after seven familiarization sessions. Copyright © 2022 Mirković, Đurić, Sember, Knezevic, Pajek, Mirković and Mirkov.

The purpose of the study was to evaluate four tests of explosive force production (EFP). Specifically, the main aims of the study were to assess the reliability of different EFP tests, to examine their relationship with maximum muscle strength, and to explore the relationship between EFP tests and functional movement performance. After an extensive preliminary familiarization with the tasks, subjects (n = 26) were tested on maximum explosive strength of the elbow extensor and flexor muscle, as well as on rapid elbow extension and flexion movements performed in both an oscillatory and a discrete fashion. In addition to maximum force (Fmax), four different EFP tests were assessed from the recorded force-time curves: the time interval elapsed between achieving 30% and 70% of Fmax (F30-70%), the maximum rate of force development (RFD), the same value normalized with respect to Fmax (RFD/Fmax), and the force exerted 100 ms after the contraction initiation (F100 ms). Excluding F30-70%, all remaining EFP tests revealed either good or fair reliability (intraclass correlation coefficients being within 0.8-1 and 0.6-0.8 intervals, respectively) which was also comparable with the reliability of Fmax. RFD and F100 ms demonstrated a positive relationship with Fmax, but not T30-70% and RFD/Fmax. Stronger elbow flexor muscles also demonstrated higher values of RFD and F100 ms than weaker elbow extensor muscles, while no difference was observed between either T30-70% or RFD/Fmax recorded from two muscles. Despite the simplicity of the tested movement tasks, the relationship observed between the EFP tests and the peak movement velocity remained moderate and partly insignificant. It was concluded that most of the EFP tests could be reliable for assessing neuromuscular function in their muscle-force- (or, indirectly, muscle size) dependent (such as RFD and F100 ms), or muscle-force-independent (T30-70% and RFD/ Fmax) forms. However, their "external validity" when applied to assess the ability to perform rapid movements could be questioned. © Springer-Verlag 2003.