Acute Effects of Different Warm-Up Protocols in Competitive Young Swimmers

Several warm-up strategies are commonly employed by athletes to optimize athletic performance and minimize the risk of injury. Recently, Post-Activation Performance Enhancement (PAPE) has been demonstrated to be effective in improving athletic performance. Nevertheless, the difference with the general warm-up is still unclear and poorly studied. Conventionally, short-term performance improvements achieved after brief periods of maximal activity have been attributed to PAP, a muscle memory mechanism that generates involuntary and short-lived effects (\~28 seconds). This condition appears to be activated only by a history of localized maximal contractions. In the literature, various conditioning protocols with differing durations and intensities have been explored, often finding conflicting results in terms of athletic performance. In swimming, few PAPE warm-up protocols outside the pool have been studied, despite their potential usefulness considering the waiting times before competitions. Therefore, this study explores the effects of three different warm-up protocols in young swimmers. Specifically, different exercise protocols will be included in the athletes' usual warm-up routine, aimed at improving athletic performance through PAPE effects. In line with existing literature, the performance parameters examined are the countermovement jump (CMJ) and the times recorded for covering race distances ( 25 m, 50 m, 100 m). In addition, skin temperature, heart rate (HR), muscle oxygen saturation (SmO2), and perceived exertion (RPE) are also measured after the protocols to investigate possible relationships with performance measures. Nevertheless, the primary aim of this study is to compare different warm-up protocols in young swimmers to maximize their athletic performance.