Potentiation with Overspeed for Jump Height Enhancement: An Analysis of Factors Distinguishing Responders from Non-Responders

Featured Application

Three sets of five repetitions of band-assisted vertical jumps (30% body mass reduction) with a 1-min intra-set rest provide jump height enhancement. Improvement can be seen after three minutes, but individualization is needed due to variability in the time required for peak performance and individual factors that contribute to the magnitude of the effects. Individuals who possess greater muscular strength may benefit more.

Abstract

(1) Background: This cross-over study aimed to assess the effectiveness of jump height (JH) enhancement after post-activation performance enhancement (PAPE) protocol based on assisted band jumps and to determine factors distinguishing responders (RS) and non-responders (NRS) based on morphological and functional factors. (2) Methods: Ten males aged 20–23 years with relative strength in back squat 156 ± 14% body weight participated. The conditioning activity, based on three series of five repetitions of assisted jumps with a band (30% of body mass load reduction) with one minute rest between series, was introduced. (3) Results: The two-way repeated measures ANOVA showed a significant interaction between effects (F = 7.78; p-eta = 0.30; p < 0.01). Comparison with the Bonferroni test showed that JH was higher than the baseline in the 3rd minute (p = 0.02; ES = 0.30) in the 6th (p < 0.01; ES = 0.39), and in the (9th p < 0.01; ES = 0.32) in an experimental condition. No factor statistically significantly distinguishes RS and NRS, but due to effect size (ES) relative strength (ES = −0.80), baseline jump ability (countermovement jump ES = −0.74; squat jump =−0.59), limb symmetry index (ES = −0.56) can be considered to contribute the most to positive effects. (4) Conclusions: The provided PAPE protocol is effective in enhancing JH but optimal rest should be established individually. Individuals characterized by greater muscular strength may benefit the most, but further consideration is needed.

1. Introduction

Post-activation performance enhancement (PAPE) is a temporary improvement in physical performance following a conditioning activity (CA) [1,2]. To simplify, the PAPE effect refers to improvement in subsequent tasks, following muscle activity with appropriate intensity and rest period that provides neuromuscular activation. The PAPE effect occurs after a brief delay due to increased body temperature, enhanced neural drive, intracellular fluid shifts, and heightened myosin light-chain phosphorylation in type II muscle fibers. However, it is negatively affected by fatigue [3,4,5]. Rassier and McIntosh stated that PAPE results from increased excitation and reduced fatigue [5].

PAPE is useful for training and competition purposes, leading to increased attention in the literature on physical performance [3,6,7]. Research focuses on effective protocols and factors influencing the magnitude of change [8]. Individual responses vary, necessitating the exploration of factors associated with these differences [9]. The application of PAPE for immediate performance enhancement has been studied in various CA protocols, including dynamic [10,11] and isometric actions [12]. In resistance exercises, an external load intensity of 60–90% 1 RM with low repetitions and sets, or isometric contractions for 3–5 s in a few sets, is recommended. Performance improvements are typically seen after 3 min, with optimal effects after 7–10 min [4,10,13]. Additionally, plyometric exercises, such as differential bouts of jumps, have shown potential for enhancing performance in the upper and lower body as well [6,14,15]. The mechanisms underlying the PAPE effect in response to plyometric exercises are attributed to the stimulation of the nervous system and the concurrent reduction in the energy expenditure of the working muscles [5].

However, in terms of using plyometrics for acute performance enhancement, less is known about the usefulness of assisted band jumps, which are classified as an overspeed exercise [16]. Overspeed exercises are employed to help individuals break through velocity barriers that they cannot normally achieve. This can be accomplished by reducing body mass, such as using elastic bands that provide assistance during jumps [16]. These exercises enable faster movements and enhanced jumping capability by decreasing effective mass and increasing peak acceleration [17]. Overspeed exercise as CA remains relatively unexplored; thus, long-term effects in jump improvement have been seen [15,16,17]. Short, fast contractions in these exercises utilizing elastic energy during the stretch-shortening cycle require low energy expenditure, minimizing fatigue while maintaining neural activation, potentially enhancing subsequent performance [17]. Markovic et al. [18] conducted tests on the effects of overspeed exercises both on countermovement jumps (CMJ), which use the stretch-shortening cycle, and squat jumps (SJ), which involve only a concentric phase. They found similar improvements in jumps after overspeed training. However, the increase in CMJ height did not align with changes in power output. The authors suggested that alterations in the movement pattern during CMJ might explain the observed results. Therefore, concentric testing may be more appropriate for better assessing potential changes in performance.

Individual responses vary for CA; factors influencing these differences are still being explored [9]. CA effectiveness may depend on baseline performance levels, strength, and training experience [8,19,20]. For example, Krzysztofik et al. [21] found that while some individuals improve jump height with the same plyometric protocols, others do not respond or perform negatively. Using loaded back squats, Poulos et al. [22] showed that stronger individuals (greater muscular strength) gain more benefits after CA. In this context, Seitz and Haff [8] showed that weaker individuals may benefit more from lower loads. These terms raise the question of how plyometric overspeed exercise-assisted band jumps affect individual response performance, which can vary. Also, the type of CA may bring various results [8,21]; therefore, it seems interesting to resolve this issue due to the lack of observation regarding overspeed exercises. It could be suspected that due to the relatively low external load, potentially weaker individuals may react positively, but it remains open to whether this stimulus will be enough for those with greater muscular strength. Also, other factors, such as the eccentric utilization ratio or limb symmetry index, potentially affect performance but remain unexplored in terms of PAPE effects [23,24]. Studies that consider factors affecting PAPE effects remain unexplored due to morphological factors. Indeed, body mass index (BMI) is generally considered reliable for assessing general health and performance, but it is unknown if any association with change magnitude after CA exists. Moreover, BMI does not provide exact information about the amount of muscle tissue and body fat, thus, this index is a simple indicator for body weight assessment. It has been observed that individuals with higher BMI values are more likely to experience a decrease in physical performance; however, to date, no study has addressed this issue in acute conditions for PAPE effects [25,26].

The advantage of using plyometric exercises to induce PAPE is their significantly easier application in pre-competitive scenarios compared to heavy resistance exercises, which demand more time or specialized equipment [27]. However, the provided literature indicates some gaps. There is a lack of observations considering overspeed exercises as a conditioning activity, which may offer an alternative approach for acute performance enhancement. Overspeed exercises allow for higher nervous system activation due to the requirements of breaking the natural velocity capabilities and, therefore, muscle contraction with high velocity. Additionally, the requirement for energy is not elevated due to muscle contraction with reduced external resistance, which potentially limits fatigue and, with joint elevated nervous system excitation, would lead to performance enhancement [16,28]. This potentially can translate into acute performance enhancement in the subsequent task [1,5,8]. Also, whereas in a protocol based on high-intensity resistance efforts, such as the PAPE protocol, some individual factors were described in terms of plyometrics, there is a lack of data considering individual factors that affect the magnitude of change. Knowledge of these factors can aid in better individual selection of CA to optimize performance.

Therefore, to address the indicated issues, this study aimed to assess the effectiveness of jump height (JH) enhancement in response to the PAPE protocol based on assisted band jumps and to determine factors distinguishing responders (RS) and non-responders (NRS) based on morphological and functional factors. We hypothesize that introducing CA would increase jump height, but the magnitude of change and time to peak performance would differ due to individual characteristics. The provided results could help practitioners acutely improve performance for competition or training purposes, as well as indicate factors whose presence may be associated with the magnitude of effects of overspeed exercise in jump height acute enhancement.

2. Materials and Methods

2.1. Sample Size Calculations

The sample size calculation for this study was conducted using G*Power software (v3.1.9.7) [29]. For adopted statistical methods, we set the parameters as follows: an effect size (ES) of 0.03, a power of 0.8, and an alpha level of 0.05. The study design included two conditions (experimental and control) and four measurement points (baseline, 3rd, 6th, and 9th minute). Based on these inputs, the software determined that 18 measurements were required. Given the cross-over design of the study, these 18 measurements were considered as separate measures, necessitating 9 participants. To account for a potential 10% dropout rate, the final sample size was increased to 10 participants [30]. This adjustment ensured that we could obtain a total of 20 measurements, with 10 in the control condition and 10 in the experimental condition.

2.2. Participants

Ten males aged 20–23 years with relative strength in back squat 156 ± 14% body weight, with a minimum of two years of continuous resistance training, participated in this study. All participants were volunteers who were briefed on the study’s procedures and potential risks. They provided written informed consent and were informed that they could withdraw from the study at any time. Each participant completed a medical questionnaire detailing their musculoskeletal, cardiovascular, neurological, and metabolic health history. Participants were instructed to refrain from strenuous physical activity, alcohol, and ergogenic substances like caffeine during the study period. They were also asked to maintain their regular sleep, diet, and hydration routines. The exclusion criteria were the previous musculoskeletal injury in the last 6 weeks, inability to perform back squat with at least 120% of body mass, and the use of doping substances.

2.3. Study Design

The study included three meetings separated by five days. During the first meeting, in the morning (7–11 a.m.), participants completed the body morphological measurements (body height and weight). In the afternoon (2 p.m.), functional tests were performed in the sequence of jump tests (including squat jump, countermovement jump (the eccentric utilization ratio was calculated), and single leg squat jump (for both sides; limb symmetry index was calculated)) and then the one-repetition maximum (1 RM) in the back squat was verified. After that, participants also were familiarized with the conditioning activity protocol. The randomization was performed using a tool accessible at randomizer.org (accessed on 2 April 2024). During the second session, group A performed a conditioning activity, whereas group B was involved in the control condition. During the third session, cross-over occurred, group B performed the PAPE protocol, and group A performed the control protocol. The study design is presented in Figure 1.

2.4. Measurements

2.4.1. Body Morphology

Body height was measured with an anthropometer (GPM Anthropological Instruments, DKSH Ltd., Zürich, Switzerland) following ISAK guidelines [31]. Body mass was assessed using an InBody230 device (InBody Co., Ltd., Cerritos, CA, USA), following standardized bio-impedance (BIA) protocols [32]. The device has a confirmed reliability [33]. Participants were instructed to avoid physical activity, food, and drink for at least eight hours prior and not to empty their bladders immediately before the assessment. BMI was calculated using the formula: BMI = kg/m².

2.4.2. Jump Testing

Before testing, participants performed the standard warm-up that included a 5-min 6 km/h run, dynamic joint mobilization, and two sets of 10 bodyweight exercises, such as air squats, lunges, and hip thrusts, with a 60-s rest between sets. Countermovement jumps (CMJ) and squat jump (SJ) were performed following the guidelines of Comfort et al. [34] and Petronijevic et al. [35]. In CMJ, participants maintained a consistent technique, lowering their center of mass and squatting to approximately 90 degrees (downward movement) before jumping for maximum height, ensuring simultaneous takeoff and landing with both feet. In SJ, participants first lowered their bodies to 90 degrees in their knees, waited three seconds, and then performed a jump. In the single-leg version, the procedure was repeated. Participants performed three to five trials for every test with at least one minute of rest. The order of the tests was randomized. The best results were considered in the analysis and calculation of further indices. The Chronojump contact mat (Chronojump Boscosystem, Barcelona, Spain) was used for jump measures, and the device’s reliability was confirmed [36]. The squat jump was introduced in testing sessions. Tests were conducted three minutes before the CA, and then three, six, and nine minutes after the protocol.

2.4.3. Eccentric Utilization Ratio (EUR)

The eccentric utilization ratio (EUR) was calculated as the ratio of performance between the countermovement jump (CMJ) and the squat jump (SJ), offering insights into an athlete’s slow stretch-shortening cycle (SSC) capability. An ideal EUR is approximately 1.1, meaning the CMJ score should be about 10% higher than the SJ score [23].

2.4.4. Limb Symmetry Index (LSI)

The limb symmetry index (LSI) was calculated based on single-leg SJ from the formula: (SJ height left (cm)/SJ height right (cm)) × 100%. A value closer to 100% is considered as no asymmetry [24].

2.4.5. One-Repetition Max in the Back Squat

The one-repetition maximum (1 RM) for the back squat was determined using the Vitruve VBT device (Vitruve, SPEED4LIFTS S.L., Madrid, Spain), which relies on the relationship between load and velocity. This device is known for its reliability [37,38,39]. The linear transducer Vitruve VBT was placed on the floor with the line attached to the bar. Before the set, the appropriate load was input into the Vitruve App, which provides kinematics of performed repetitions.

The protocol was based on principles provided by Signore [39]. Participants started with a general warm-up that included a 5-min run at 6 km/h, dynamic joint mobilization, and two sets of 10 bodyweight exercises, such as air squats, lunges, and hip thrusts, with a 60-s rest between sets.

Next, a specific warm-up was conducted based on performing submaximal back squats with incremental load to prepare for an attempt with maximal load. Participants performed a maximum deep back squat with an empty bar to establish their individual maximum depth. The goal was to reach the lowest position possible while maintaining proper technique and safety, which involved bending the knees and lowering the torso until the top of the thighs at the hip joint were below the knees. This depth was consistently used for the CA and each back squat repetition, monitored by setting parallels to match the height. An investigator and spotters were present to ensure proper performance and safety throughout all sets for consistency. One spotter stood behind the participant, two others stood on the sides to directly control the bar, and the fourth controlled the hip position to ensure the repeatability of back squat depth. The parallels were also set to the appropriate height to allow maximal squat depth and provide safety in case of failure. A specific warm-up included 4 sets with 15–5 reps with incremental load to achieve a mean velocity 0.5 m/s. In detail, the first specific warm-up set involved 12–15 repetitions with an empty bar followed by 10–12 repetitions at 50% of the 1 RM (mean velocity 1.0–1.2 m/s). Then, participants completed 2–3 sets of 5 repetitions at 60–80% of the 1 RM (mean velocity 0.5–0.75 m/s).

After the specific warm-up, a progressive incremental test for the back squat was conducted, starting with a load of 80% 1 RM for 3 repetitions (mean velocity). The load was increased by 5–10% increments. When the mean velocity dropped below 0.5 m/s, sets were reduced to 2 repetitions, and once the mean velocity dropped below 0.25 m/s, only 1 repetition was performed. The test continued until failure or for a maximum of 5 sets, with 3–5 min rest intervals between sets.

2.5. Conditioning Activity

The conditioning activity, based on three sets of five repetitions of assisted jumps with a band that provides a 30% body weight [40,41] load reduction with one minute rest between series, was introduced. The assisted band jump was performed according to Wilson et al. [42]. The elastic band (power band, Just7gym, Wilkszyn, Poland) was suspended above the participant’s head, who started in a standing position. To determine the attachment height of the band and verify the load reduction it provided (aiming for a 30% reduction in body weight during the lowering of the center of gravity before jumping), a weight representing the desired value (30% of body weight) was attached to the band at a specific height [40,41]. After selecting the appropriate band and its attachment height, the subject placed the band under their armpits and, holding it in their hands, performed a series of 5 assisted band jumps. The control condition included running at 6 km/h for 4 min, which corresponded to the duration of the CA protocol. This was performed to maintain individuals’ readiness to perform jump testing in control settings. This approach was utilized previously [12].

2.6. Statistical Analysis

Statistica 13.0 software (StatSoft, Cracow, Polska) was used for statistical analysis conduction. The significance level was set at p < 0.05. Data normality was confirmed with the Shapiro–Wilk test. Results were expressed as mean ± SD and 95% confidence intervals. Further, data variance homogeneity was assessed using Levene’s test, and sphericity was assessed using the Mauchly test. Then, two-way repeated measures ANOVA was performed (time x condition) to identify differences between conditions. The effect sizes were measured using partial eta squared (pη²) and categorized as small (<0.01), medium (0.06), or large (≥0.14). Next, the Bonferroni post hoc test was introduced to compare the results in detail. For this purpose, dCohen effect size was used and interpreted as small (0.2 ≥ d), medium (d > 0.2; d < 0.79), and large (d ≥ 0.8) [43]. The chi-squared (χ²) test assessed the time to peak performance significance. The typical error was calculated based on the absolute difference between the best jump post-CA and baseline values and calculated according to the formula: TE = SDdiff/√2. The method previously employed in sports science experiments [44] categorized participants into three groups based on their jump height changes: (a) responders, if their jump height increased by more than twice the TE value; (b) non-responders, if their jump height change remained within the TE value; and (c) negative responders, if their jump height decreased by more than twice the TE value. However, no one was classified as a negative responder. Therefore, for two categories, the student t-test for the independent sample was conducted to compare responders (RS) and non-responders (nRS). To assess the difference, the dCohen effect size was implemented.

3. Results

Table 1. Descriptive statistics of study participants.

Variable	Mean ± SD (95% CI)
Body height (cm)	183.9 ± 25.3 (165.7–202)
Body weight (kg)	74.2 ± 12.1 (65.6–82.8)
BMI (kg/m2)	22.4 ± 4 (19.6–25.2)
Back squat 1 repetition max (kg)	117.4 ± 31.4 (94.9–139.9)
Relative strength (1 RM/body weight; kg)	156.2 ± 26.7 (137.1–175.2)
Gym experience (years)	3.5 ± 1.8 (2.2–4.8)
Training volume/week (minute)	321 ± 118.4 (236.3–405.7)
Countermovement jump (cm)	35.3 ± 6.3 (30.8–39.8)
Eccentric utilization ratio (cm)	1.0 ± 0.1 (0.9–1.1)
Limb symmetry index (%)	97.1 ± 8 (91.4–102.8)

presents the statistical characteristics of study participants considered morphological and functional variables.

Table 2. Jump height due to the time of measurement for the experimental and control conditions.

Time (min)	Experimental	Control
	Mean ± SD (95% CI)
Baseline (cm)	35.7 ± 6.1 (31.3–40.1)	35.5 ± 6.1 (31.1–39.8)
3rd (cm)	37.8 ± 7.8 (32.2–43.4)	35.1 ± 6 (30.8–39.4)
6th (cm)	38.4 ± 7.4 (33.1–43.6)	34.6 ± 6.5 (29.9–39.3)
9th (cm)	38.1 ± 8.6 (32–44.3)	34.7 ± 6 (30.4–38.9)

shows jump height for experimental and control conditions in consecutive measures. Two-way repeated measures ANOVA revealed no significant effects for intervention (F = 0.70; p-eta = 0.03; p = 0.41) and time (F = 2.30; p-eta = 0.11; p = 0.08), but the interaction between effects was shown as significant (F = 7.78; p-eta = 0.30; p < 0.01). Detailed comparison with the Bonferroni post hoc test showed that the consecutive measures of jump height in the experimental condition were higher than the baseline in the 3rd minute p = 0.02; ES = 0.30 in the 6th p < 0.01; ES = 0.39, and in the 9th p < 0.01, ES = 0.32 (Figure 2).

In the next step of the analysis, time to peak performance (best results appearance) was considered. Two individuals’ peak performance appeared in the 3rd minute, five in the 6th minute, and two in the 9th minute. One participant did not achieve any improvement. However, the chi-square analysis showed that the observed frequency was insignificant (χ² = 3.6; p = 0.3).

Based on the typical error calculation, the cut-off value for distinguishing responders (RS) and non-responders (nRS) was 3.29. Based on this, five individuals were indicated as RS and five as nRS. Then, a Student t-test for independent samples was performed (

Table 3. Student t-test for independent results for comparisons between responders and non-responders groups.

Variable	Responders	Non-Responders	ES	t	p
	Mean ± SD (95% CI)
BMI (kg/m2)	21 ± 5.4 (14.3–27.6)	23.9 ± 1 (22.6–25.1)	0.75	1.19	0.27
Back squat 1 repetition max (kg)	122.4 ± 33.6 (80.7–164.1)	112.4 ± 32.1 (72.6–152.2)	−0.30	−0.48	0.64
Relative strength (1 RM/body weight; kg)	166.5 ± 27 (133.1–200)	145.8 ± 24.6 (115.3–176.3)	−0.80	−1.27	0.24
Gym experience (years)	4 ± 2 (1.5–6.5)	3.0 ± 1.7 (0.8–5.2)	−0.53	−0.85	0.42
Training volume/week (minute)	336 ± 131.5 (172.8–499.2)	306 ± 117 (160.8–451.2)	−0.24	−0.38	0.71
Countermovement jump (cm)	37.6 ± 7.8 (28–47.2)	33.1 ± 3.9 (28.2–37.9)	−0.74	−1.17	0.28
Squat jump baseline (cm)	37.5 ± 6.5 (29.5–45.6)	33.9 ± 5.8 (26.7–41.1)	−0.59	−0.94	0.37
Eccentric utilization ratio (units)	1 ± 0.1 (0.9–1.1)	1 ± 0.1 (0.8–1.2)	−0.08	−0.13	0.9
Limb symmetry index (%)	99.4 ± 10.8 (85.9–112.8)	94.8 ± 3.7 (90.2–99.5)	−0.56	−0.89	0.4

) to compare individuals’ characteristics, considering morphological and functional factors. The results showed no difference was statistically significant (p > 0.05), but effect size values suggested that some values could be meaningful. Indeed, RS relative strength was higher than nRS with large ES (ES > 0.80). Further, BMI and asymmetry in the legs, due to jump height ability, were higher in nRS with medium ES (0.30 < ES < 0.80). Also, medium ES due to higher values in RS was observed in CMJ and SJ baseline and gym experience. The ES was considered trivial for the rest of the variables (ES < 0.30).

4. Discussion

This study aimed to show the effectiveness of overspeed exercise as a conditioning activity for acute improvement in jump height performance. Moreover, an analysis was extended to consider factors that may be associated with the magnitude of CA effects. The results confirm the potential usefulness of assisted band jumps as a tool for enhancing jumps as a subsequent task. However, differences were observed in time to peak performance, which indicates the need for individualization of rest time. Moreover, analysis of responders and non-responders showed that individual characteristics play a role in the magnitude of change. Practitioners should use a 30% bodyweight reduction in assisted band jump in five repetitions with three sets separated by one minute rest to enhance jump performance, but individual characteristics may affect time to peak performance as well as the magnitude of change. Individuals who possess greater muscular strength, and are more powerful, experienced, and non-asymmetrical individuals are more likely to gain more.

Next to high-intensity resistance exercises or isometry, a plyometric-based CA is an effective tool for acute performance enhancement [10,11,12,13,14]. A study by Barreto et al. [45] found that a set of jump exercises induces improvement in subsequent vertical jumps. Another study conducted by Tobin and Delahunt [46] reported that professional rugby union players showed improved performance in CMJ 1–5 min after performing multiple sets of plyometric conditioning activities CA. However, this study only examined the PAPE effects within the first 5 min and found no effects beyond this period, whereas in our study, the performance enhancement was also visible after nine minutes. Conversely, in another study conducted by Sharma et al. [47] involving male collegiate soccer players, jump height improvement was observed even 10 min after a plyometric CA. Bogdanis et al. [48] found that plyometric activity is also effective in improving long jump performance. It was shown that one of the important factors for evoking the PAPE effect is a similarity between conditioning activity and subsequent tasks [3,4]. In these terms, various jumps lead to improvement in subsequent jump tasks due to the use of the same muscle groups and similar patterns of neurological activity [1]. Moreover, the PAPE effect is related to the increase of nervous system activation with joint limitations of muscle energy expenditure during plyometric activity [5,49]. In these terms, assisted band jumps allow for the breaking of the velocity barriers, which leads to higher velocity contraction; therefore, nervous system activity is enhanced. This translates into performance enhancement in subsequent jump tasks [1].

Our study shows some inconsistency in the appearance of peak performance after CA. This was observed in many studies [13]. Despite this, it can be assumed that the general improvement was observed after three minutes post-CA; thus, the time when individuals achieved the best results varied. The meta-analysis by Wilson et al. [13] also supports the observation that results improvement is typically seen after a 3-min rest period. Nonetheless, it is important to note that some individuals may require longer rest intervals, up to 6 min, to achieve peak performance. Dobbs et al. [4] further suggest an optimal rest range of 3 to 7 min for peak performance. However, the variability among individuals regarding peak performance timing is significant, with individual responses to PAPE protocols varying greatly regardless of various factors.

In our study, the higher relative strength, measured based on back squat 1 RM with ratio to body mass, contributed the most to a positive response due to the magnitude of change. This is in line with the observations of other authors. Guo et al. [50] showed performance enhancement was linked to the individuals’ baseline muscular strength. Stronger ones demonstrated a more pronounced PAPE effect after performing a set of submaximal back squats. In contrast, weaker participants reached their peak PAPE response sooner than their stronger counterparts [50]. Elevated muscle strength levels help to avoid fatigue, as well as is associated with better utility of fast-twitch fibers, which contribute the most to ballistic tasks such as jumps [7]. The study by Seitz and Haff [8] and Formiglio et al. [9] also state that individuals with greater muscular strength may benefit more after the PAPE protocol for enhancement in subsequent tasks. It is related to advanced neuromuscular adaptations and greater muscle fiber recruitment capabilities. Their heightened neuromuscular efficiency allows for more effective exploitation of the increased muscle readiness following CA stimuli [9,51]. Enhanced force development rate and robust tendons can also contribute to the superior performance enhancements observed [13].

Also, baseline jump height or lower limb symmetry contributes positively to the magnitude of change. However, in a study by Masel and Maciejczyk [52], the group of RS and nRS had relatively similar results of baseline jumps; thus, in the mentioned study, other factors had meaning in CA effectiveness. Gym experience was another factor that seemed to be associated with the magnitude of change. Responders were more experienced. A study by Berning et al. [53] also revealed that more experienced individuals were more responsive after CA in jump height enhancement. However, the mentioned factors could be associated with each other, though it can be suspected that more experienced individuals in training would possess greater muscular strength and be more powerful [54]. In terms of symmetry, PAPE literature does not provide many clear observations. However, it is generally recommended to avoid asymmetry in limbs due to decreased injury risk as well as elevated performance [55]. When both sides of the body contribute equally, the neuromuscular response to CA stimuli is more effective, leading to better performance enhancements [56]. Symmetry also promotes improved coordination and neuromuscular efficiency, essential for maximizing PAPE’s benefits [57]. Additionally, maintaining symmetry helps distribute loads evenly, minimizing the risk of compensatory movements and injuries that could otherwise diminish the PAPE effect [51].

In our study, BMI negatively contributes to the magnitude of change. Indeed, morphological factors were also not often explored for PAPE contribution. BMI is not an ideal index because the tissue type in body mass is not considered, but the elevated value is often recognized negatively. However, it can be assumed that higher body mass (and therefore BMI) makes it more difficult to perform jumps due to the greater load required to move [58]. Individuals with a healthy BMI are likely to have an optimal balance of muscle and fat, which can enhance the neuromuscular response to high-intensity stimuli and maximize the PAPE effect [59]. Conversely, a high BMI, often associated with excess body fat, may hinder movement efficiency and neuromuscular function, reducing the effectiveness of PAPE [60].

We are aware that this study has some limitations. Firstly, more individuals in the analysis of responders and non-responders would provide more insight into the considered issue. More individual characteristics, such as muscle stiffness and the rate of force development ability would also deepen the analysis. Prolonging the measurement time could show the time with maintenance performance enhancement with greater accuracy. Also, other load reductions should be investigated to assess the optimal value for performance enhancement. Another factor that could be added is the consideration of sex differences; therefore, a study on the female group is required. On the other hand, this study has some strengths. It presented a relatively simple application protocol for acute performance enhancement, which constitutes high application value for practitioners. Moreover, to date, not many studies have directly considered factors that may affect the magnitude of effects through individual characteristics that extend current knowledge about the PAPE effect.

5. Conclusions

The findings of this study offer valuable insights for coaches and athletes aiming to enhance performance through the PAPE protocol. The CA, which involves three sets of five repetitions of assisted band jumps with a 30% load reduction and one-minute rest intervals, is effective in improving performance, with noticeable improvements three minutes after the conditioning activity (CA) that lasts for at least the next six minutes. Practical implications include timing peak performance to occur within three to nine minutes post-CA, tailoring rest periods to individual athletes to optimize performance gains, and focusing the training on developing greater muscular strength, power, and experience, and reducing asymmetry in lower limb jump abilities. The protocol can be easily incorporated when acute jump ability enhancement is required in preparation for targeted activity. By leveraging these findings, coaches and athletes can more effectively enhance performance through a targeted and individualized approach using the PAPE protocol.

Future research should focus on increasing the number of participants in both responder and non-responder groups, which provide more robust data. Including individual characteristics like muscle stiffness and rate of force development could offer deeper insights into responsiveness. Extending measurement duration would help identify how long performance enhancements last. Exploring various levels of load reduction could determine optimal conditions for performance enhancement. Including female participants is essential to understand sex-specific responses.