# Effect of Post-Activation Potentiation on Weightlifting Performance and Endocrinological Responses
## 1 Introduction
Since peak RFD has been found to be related to vPV [4] and is optimised during an MTCP at 120% 1 RM power clean, it could be hypothesised that utilising a 120% supramaximal pull of 1 RM clean may elicit a potentiating effect on clean performance, with weightlifters often performing this derivative during training at loads between 100 and 120% 1 RM. Of further consideration is the effect these variables have on barbell displacement. [PERSON] [10], [PERSON] [13], and [PERSON] et al. [14] have noted that greater vPV results in greater barbell displacement, which improves the likelihood of a successful lift. Therefore, utilising exercises such as the pulling derivatives, which improve these key characteristics in weightlifting, should be considered. Additionally, when attempting to induce PAP, the biomechanical similarity of the stimulus to the subsequent activity must be considered [15]. [PERSON] et al. [16] has noted that the use of pulling derivatives enables practitioners to overload biomechanically identical movements above full lift 1 RM levels, without the need to receive the weight. Therefore, utilising a supramaximal clean pull may elicit positive effects on kinetic and kinematic clean performance. Consideration of time between the PAP stimulus and the performance measure has a large influence on the effectiveness of PAP, with the literature suggesting that less than 2 min rest will not enable the dissipation of fatigue to an extent great enough to allow for the maximal expression of PAP [1; 6; 15; 17]. Current research has shown that the onset of PAP will typically occur between 3 and 6 min post-conditioning stimulus in stronger subjects and between 6 and 9 min in weaker subjects [6]. During weightlifting competitions; however, individuals have 1 min between when the bar is loaded and their lift, or 2 min if they are following themselves. Given the competitive nature of backroom tactics, and the other clock-stopping activities (i.e., changes in bar load, changes in lifter sequence, etc. ), the time an athlete may take between their last warm up lift and platform lift, or between platform lifts, will vary depending on the scenario. From an applied practice standpoint, providing a potentiating stimulus at around 3 min prior to the next competition platform lift may elicit an improvement in performance without having to perform a full lift, thus potentially conserving energy. Finally, given that heavy resistance loading has been shown to produce acute increases in serum testosterone [18], which is considered critical for optimal force production [19] and potentially psychological priming [20], testing this association may reveal mechanistic factors causative to changes in performance following a priming intervention, should any be noted. Furthermore, given the antagonistic relationship between testosterone and cortisol, it is also considered necessary to measure the testosterone to cortisol ratio, thus accounting for environmental stress and arousal, which may further explain performance [21; 22]. To the authors' knowledge, there is no existing literature on the effect of supramaximal clean pulls on clean performance. Therefore, the purpose of this study is two-fold: (1) to investigate the effect supramaximal clean pulls have on clean kinetics and kinematics and (2) to investigate the effect this has on hormonal status, since heavy resistance loading has been shown to produce large acute increases in serum testosterone (T) [18], which has been associated with weightlifting [23], and thus may be a contributing factor to the PAP mechanism. Given the practical limitations of competition, a 3 min recovery period between the conditioning stimuli and performance has been adopted.