<b>The effect of plyometric exercises on improving the perceptual-motor abilities and physical proficiency of lifeguards after a period of non-training during the prevalence of Covid -19 in Tehran province</b>

Abstract The aim of this study was to investigate the effect of plyometric exercises on improving the perceptual-motor abilities and physical proficiency of lifeguards after a period of non-training during the prevalence of Covid -19 in Tehran province. 24 volunteer female lifeguards aged 20 to 25 years were selected in Tehran province with More than 2 years work experience and divided into two categories (-Experimental group –Control group). In this way, for the experimental group, plyometric exercises in the form of selective darbee movements include the first movement in 3 sets of 10 repetitions of lunges with the right foot - 20 long knee jumps - opposite leg repetition, the second movement in 3 sets of 10 repetitions. The third was selected in 3 sets of 10 correct long repetitions - 20 long knee jumps - repetition. The experimental group performed their own exercises during 4 weeks of 3 sessions with a total of 12 sessions of various plyometric exercises. The research variables included response time velocity (reaction time), explosive power and large body coordination (dive length). In order to measure the reaction time, the 8-Direction reaction time machine was used, in order to measure the perceptual-motor ability of the rescuers, the 8-Direction reaction time machine was used, and in order to evaluate the physical proficiency, the dive length test was used. SPSS software version 24 was used to analyze the data. ANKOVA test was used to test the hypotheses. The results showed that plyometric exercises had a significant difference in post-test compared to pre-test on all three variables (p &lt;0.05). Therefore, the findings of this study suggest that plyometric exercises can improve the perceptual motor skills and physical skills of lifeguards. Keywords: Plyometric practices, Reaction time, Explosive-power, Course body co-ordination, Life Guards