Optimal Timing for Post-Activation Potentiation in Women Collegiate Volleyball Players

Effects of Upper-Body and Lower-Body Conditioning Activities on Postactivation Performance Enhancement During Sprinting and Jumping Tasks in Female Soccer Players

ABSTRACT

Santos da Silva, V, Nakamura, FY, Gantois, P, Nogueira Gouveia, JN, Peña, J, Beato, M, and Abade, E. Effects of upper-body and lower-body conditioning activities on postactivation performance enhancement during sprinting and jumping tasks in female soccer players. J Strength Cond Res 38(2): 342-349, 2024-This study aimed to investigate the postactivation performance enhancement (PAPE) effects of "specific" (half-back squat) and "nonspecific" (bench press) conditioning activities on sprinting and jumping performances in female soccer players. Fourteen players (mean ± SD : age = 22.3 ± 4.0 years; body mass = 60.2 ± 7.8 kg; height = 164.1 ± 4.2 cm) competing at national level (first League) participated in this within-subject crossover study. The players performed a warm-up protocol including 3 sets of 3 repetitions of half-back-squat or bench press exercises at 90% 1RM or a warm-up protocol without lifting weights (i.e., control condition). Forty-meter shuttle sprints (20 + 20 m with change of direction [COD-180°]), countermovement jump (CMJ), and horizontal jump (HJ) performances were recorded 6 minutes after the conditioning activities protocols or the control condition. Nonsignificant large positive effects were found for the HJ after the half-back-squat (ES = 1.68; p > 0.05) and bench press (ES = 1.68; p > 0.05) protocols. Although nonsignificant, HJ changes ( Δ = 0.07 m) were greater than the smallest worthwhile change (0.02 m) and standard error of measurement (0.03 m) after both conditioning activities. Moreover, no significant changes were found for sprint and CMJ performance after neither half-back-squat nor bench press protocols ( p > 0.05). In conclusion, both specific and nonspecific conditioning activities using heavy loads (i.e., 90% 1RM) may be suitable to enhance individual HJ. Finally, both conditioning activities are potentially ineffective for increasing sprint and CMJ performance in the context of this study.

Post-Activation Performance Enhancement (PAPE) Increases Jumping Power in Elite Female Volleyball Athletes

This study investigated PAPE effects of two conditioning activities (CA) and recovery times on the peak jumping power (PP) of elite female volleyball athletes. Players performed CA separately: three sets of three repetitions of back squats with 85% of 1RM (BS) or one set of five depth drops (DD). PP was measured with countermovement (CMJ) and squat jumps (SJ) before (pre-test) and two minutes (post-test 1) and six hours (post-test 2) after each CA. BS significantly reduced PP at post-test 1 (CMJ and SJ: p < 0.04, d between -0.36 and -0.28). At post-test 2, following BS, PP for both jump forms was significantly greater than at post-test 1 (p < 0.001, d between 0.54 and 0.55) and at pre-test (p < 0.048, d between 0.21 and 0.30). DD increased PP significantly (CMJ and SJ p < 0.05, d between 0.40 and 0.41) relative to pre-test at post-test 2 (there was no significant difference between pre-test and post-test 1). Comparing BS with DD, there were no significant differences (p > 0.05). The greatest PAPE effects were observed six hours after BS. CA are recommended for female athletes to improve jumping performance, but individual responses should be determined prior to use.

Post-Isometric Back Squat Performance Enhancement of Squat and Countermovement Jump

The effectiveness of isometric conditioning activity (CA) is not well described in terms of the level of performance enhancement and the presence of a stretch and shortening cycle in subsequent explosive tasks. Therefore, the aim of this study was to evaluate the effect of a maximum isometric squat as the CA and a subsequent squat jump (SJ) and countermovement jump (CMJ) height. A total of 31 semi-professional handball and soccer players were randomly assigned to two different conditions: (i) 3 sets of 3 repetitions (each lasting 3 s) of maximum isometric back squats (EXP), and (ii) no CA (CTRL). The jump height measurements were performed 5 min before the CA and approximately at the 4th and 8th minute following the completion of the CA. Due to the high inter-individual variability in the potentiation responses, the best value obtained post-CA was also analyzed. The SJ height significantly increased from baseline to the 8th minute post-CA (p = 0.004; ES = 0.31; Δ = +3.1 ± 5.0%) in the EXP condition. On the other hand, the CMJ height was significantly higher in the 4th (p = 0.001; ES = 0.23; Δ = +2.7 ± 3.7%) and 8th minute post-CA (p = 0.005; ES = 0.32; Δ = +3.6 ± 5.7%) in comparison to baseline during the EXP condition. Furthermore, SJ height significantly increased from baseline to the best time-point during the EXP (p < 0.001; ES = 0.47; Δ = +4.9 ± 4.9%) and CTRL (p = 0.038; ES = 0.21; Δ = +2.5 ± 5.8%) condition. Moreover, the CMJ height was significantly higher at the best time-points than at the baseline during EXP (p < 0.001; ES = 0.53; Δ = +5.6 ± 4.7%) and CTRL (p = 0.002; ES = 0.38; Δ = +3.1 ± 5.2%) condition. The findings from this study indicate that a maximum isometric squat, used as a CA, effectively improved SJ and CMJ height. This suggests that the presence or absence of a stretch and shortening cycle in both CA and post-CA tasks does not significantly impact the post-activation performance enhancement response.

Postactivation Performance Enhancement (PAPE) Increases Vertical Jump in Elite Female Volleyball Players

The purpose of this study was to verify if a conditioning activity was effective to elicit postactivation performance enhancement (PAPE) and to increase the performance in vertical jump (VJ) in elite female volleyball players. Eleven national Superliga-2 volleyball players (22.6 ± 3.5 years) were randomly assigned to an experimental and control group. Countermovement jumps (CMJ) were performed on eight occasions: before (Pre-PAPE) and after activation (Post-PAPE), after the match (Pre-Match), and after each of the five-match sets (Set 1 to 5). ANOVA showed significantly increased jump performance for the experiment between baseline (Pre-PAPE) and all the following tests: +1.3 cm (Post-PAPE), +3.0 cm (Pre-Match), +4.8 cm (Set 1), +7.3 cm (Set 2), +5.1 cm (Set 3), +3.6 cm (Set 4), and +4.0 cm (Set 5), all showing medium to large effect size (0.7 < ES < 2.4). The performance of the control group did not show significant increases until Set 3 (+3.2 cm) and Set 5 (+2.9 cm), although jump heights were always lower for the control group than the experimental. The use of conditioning activity generates increased VJ performance in Post-PAPE tests and elicited larger PAPE effects that remain until the second set of a volleyball match.

The Effects of Resisted Post-Activation Sprint Performance Enhancement in Elite Female Sprinters

Considering the effectiveness of resisted sprint training, and the acute enhancement of sprinting performance through locomotor post-activation performance enhancement, the main objective of the research was to determine the acute effects of resisted activation with loads of 5, 10, and 15% body mass on sprint and flying start sprint performance in elite female sprinters using resisted drag technology system. Ten elite female sprinters (age: 23.2 ± 5.4 years, body mass: 54.2 ± 6.1 kg, height: 167.4 ± 7.3 cm, personal best for 100 m: 12.05 ± 0.56 s, and for 400 m: 53.17 ± 2.76 s) performed two unresisted 20-m sprints (from a crouched and flying start) before and after a single resisted sprint loaded with 5, 10, or 15% body mass to verify the effectiveness of the activation stimulus. Compared with pre-activation, Friedman tests showed that peak velocity increased by 1.6 ± 2.2% [effect size (ES) = 0.66], 2.3 ± 1.5% (ES = 1.33), and 0.2 ± 1% (ES = 0.09), as well as peak force by 2.8 ± 2.1% (ES = 0.49), 3.5 ± 2.3% (ES = 1), and 0.5 ± 2.4% (ES = 0.14), concomitant with a significant decreased in sprint time by −0.5 ± 1.2% (ES = −0.07), −2.5 ± 1.3% (ES = −0.64), and −1 ± 1.4% (ES = −0.36) for the 5, 10, and 15% body mass post-activation, respectively (p < 0.001; for all). Furthermore, the ANOVA showed that peak power increased by 2.9 ± 2.3% (ES = 0.61), 3.8 ± 2.2% (ES = 1.05), and 2 ± 7.1% (ES = 0.22) for the 5, 10, and 15% body mass resisted-conditioning activity, respectively, with no difference between the three conditions (p = 0.003 main effect time, no interaction). Moreover, compared with the 5 and 15% body mass trials [−1.5 ± 2% (ES = −0.44), −0.8 ± 0.8% (ES = −0.44), respectively], the ANOVA showed that flying start sprint time significantly decreased by −4.3 ± 1.1% (ES = −1.25) (p < 0.001, interaction effect) after a 10% body mass resisted-conditioning activity. The results of this study indicated that resisted sprints acutely enhance sprint performance; however, their effectiveness depends on the applied load. A single resisted sprint using 10% body mass is effective at inducing a potentiating effect on subsequent 20-m flying start sprint performance in elite female sprinters. Therefore, keeping in mind the optimal load, it is recommended to perform resisted sprints as a conditioning activation when seeking to acutely enhance 20-m flying start sprint performance in these athletes.

Acute Performance Enhancement Following Squats Combined With Elastic Bands on Short Sprint and Vertical Jump Height in Female Athletes

ABSTRACT

Krčmár, M, Krčmárová, B, Bakaľár, I, and Šimonek, J. Acute performance enhancement after squats combined with elastic bands on short sprint and vertical jump height in female athletes. J Strength Cond Res 35(2): 318-324, 2021-The main purpose of this study was to compare back squats with and without elastic bands on sprint and vertical jump height. Fourteen female athletes (21.9 ± 2.3 years; 177.5 ± 6.36 cm; 66.2 ± 6.2 kg; 1 repetition maximum [1RM]/ body mass: 1.96 ± 0.14) agreed to participate. On 4 separate days, athletes walked freely for 5 minutes (CON), performed 3 sets of 4 repetitions at 85% of their 1RM with 20% or 30% (BAND20 or BAND30) of the total resistance originated from elastic bands, or performed 3 sets and 4 repetitions at 85% of their 1RM with an isoinertial load (ISO) before performance tests. Posttesting began 5 and 10 minutes after the last set of squats and included sprints over 3, 5, and 10-m, squat jump (SJ), and countermovement (CMJ) vertical jump height. The results of this study show that all postactivation performance enhancement (PAPE) protocols significantly improved 10-m sprint time (p < 0.05 to p < 0.01). Only BAND30 significantly improved 3-m and 5-m sprint times at both times of posttesting (p < 0.01). Comparison of PAPE protocols showed a significant difference when comparing BAND30 vs. ISO in SJ height in favor of BAND30 only when the best SJ height results from both posttesting times were selected (p < 0.01, g = 1.08). The results of this study suggest that all PAPE protocols were able to enhance short sprints and vertical jump height, but it seems that there is a greater trend to achieve better performance after performing the BAND30 protocol that can be seen by higher effect sizes achieved almost in all tests compared with the other PAPE protocols.

Prior Band-Resisted Squat Jumps Improves Running and Neuromuscular Performance in Middle-Distance Runners

Post-activation potentiation (PAP) conditioning has been reported to increase performance. Most research has examined PAP effects on strength/power activities, whereas the effects on endurance sports are understudied. The aim of this study was to characterize PAP conditioning stimulus effects on a subsequent 5x1 km running trial. A randomized, within subjects, repeated measures study utilized 12 male, endurance-trained athletes, who performed a full warm-up, conditioning exercise intervention (4x5 repetition maximum band-resisted squat jumps) or a control condition prior to a 5x1 km time trial run. Tests were conducted immediately prior to the intervention, after each kilometer, immediately following the 5x1 km run, and at seven and ten minutes post 5 km run. Measures included the interpolated twitch technique (ITT), evoked contractile properties, maximum voluntary isometric contractions (MVIC) plantar flexor force, drop jump, rating of perceived exertion, and heart rate. The PAP stimulus reduced the time to complete the run (3.6%; p = 0.07, d = 0.51), and decreased the time to complete kilometer one (8%; d = 1.08, p = 0.014). Jump height (p = 0.02; 9.2%) and reactive strength index (p = 0.035; 16%) increased with PAP. F100 (force produced in the first 100ms of the MVIC) and MVIC force with PAP increased at kilometers 3 (p = 0.04, d=0.84), 4 (p = 0.034, d = 0.29), and 7min post-run (p = 0.03, d = 0.60). Voluntary activation (ITT) increased at 7min post-run (p = 0.04, d = 0.59) with PAP, yet decreased at 7min post-run in the control condition (p = 0.03, d = 0.36). A prior band-resisted squat protocol decreased running time and improved neuromuscular properties in endurance athletes running 5x1 km.

The Effect of Ballistic Exercise as Pre-Activation for 100 m Sprints

The benefits of warm-up in sports performance has received a special interest in the current literature. However, there is a large gap of knowledge about the tasks to be performed, specifically in the real competitive environment. The purpose of the study was to verify the acute effects of a warm-up including ballistic exercises in 100 m running performance. In addition, a second 100 m trial was assessed to better understand the warm-up effects in training and competition. Eleven men (25.4 ± 6.2 years of age, 1.76 ± 0.08 m of height, 78.2 ± 8.6 kg of body mass) were submitted to three different protocols, in a randomized order: no warm-up (NWU), typical warm-up (WU) and WU complemented with ballistic exercises (PAP). Biomechanical, physiological and psychophysiological variables were assessed. Differences were found between the three conditions assessed in the first 100 m sprint with 7.4% and 7.6% faster performances after the WU and PAP, compared to NWU. Stride length was higher in the second part of the 100 m after PAP compared with WU. These results highlight the positive effects of warm-up for sprinting performance. The inclusion of ballistic exercises, besides being used to improve sprint performance, can increase stride length in the final of the 100 m race.

Effects of Warm-Up, Post-Warm-Up, and Re-Warm-Up Strategies on Explosive Efforts in Team Sports: A Systematic Review

BACKGROUND

In team sports, it is imperative that the warm-up improves acute explosive performance. However, the exact strategies, methods, and consequences of different warm-up practices remain unclear. A time delay between the warm-up and match and during half-time could negate the positive metabolic effects of the warm-up.

OBJECTIVES

We conducted a systematic review to synthesize and analyze the potential effects of strategies during a warm-up (before match), post-warm-up (time between the end of warm-up and the start of a match), and re-warm-up (half-time break within a match) on explosive performance in team sports. Furthermore, we examined optimal warm-up strategies based on the included studies.

METHODS

We performed a search of four databases (Web of Science, Scopus, PubMed, and ScienceDirect) for original research articles published between January 1981 and August 2017. A total of 30 articles met the inclusion criteria, and the Cochrane risk of bias tool was used to assess the risk of bias. The results of the included studies were recalculated to determine effect sizes using Cohen's d.

RESULTS

A warm-up comprising 8 sets of 60-m sprints (- 2.19%, d = 1.20) improved sprint performance. Additionally, 7 min of dynamic exercises after 5 min of jogging improved sprint (- 7.69%, d = 1.72), jumping (8.61%, d = 0.61), and agility performance (- 6.65%, d = 1.40). The use of small-sided games also seems to be a valid strategy, especially for jumping performance (6%, d = 0.8). These benefits resulted from the warm-up strategies combined with some passive rest (between 2 and 10 min) before the main performance. In this post-warm-up period, the use of heated garments could result in better outcomes than simple rest (- 0.89%, d = 0.39). However, if the transition was longer than 15 min, before entering the match, performing a re-warm-up with short-term explosive tasks to reactivate was the most effective approach (- 1.97%, d = - 0.86). At half-time, heated garments maintained better sprint (- 1.45%, d = 2.21) and jumping performance (3.13%, d = 1.62).

CONCLUSION

Applying properly structured strategies in the warm-up and avoiding a long rest in the post-warm-up improves explosive performance. Studies tend to recommend a short active warm-up strategy (10-15 min), gradually increasing intensity (~ 50-90% of maximum heart rate), and the use of heated garments soon after the warm-up to maintain muscle temperature. However, 2 min of active re-warm-up with short-term sprints and jumps should be needed for transitions longer than 15 min (~ 90% of maximum heart rate). Last, at the half-time re-warm-up, combining heated garments to maintain muscle temperature and performing an active strategy, with explosive tasks or small-sided games for 5 min before re-entering the game, resulted in better explosive performance than 15 min of resting.

Blood flow in the brain venous blood vessels of children with cerebral palsy while using Bobath therapy

In the diagnosis of the causes of neurological disorders in children’s with cerebral palsy has attached the results of Transcranial Doppler. Bobath therapy is the most innovative and effective methods of physical rehabilitation. For the determination of brain blood flow of children of preschool age with various CNS lesions for the influence of the physical therapy using the Bobath’s method, 35 children aged 4.1 ± 1.1 years were examined. That was the main group (MG). All of 72 procedures were conducted. There was also a control group (CG), the results of the brain blood flow had been studied and analyzed in 34 children aged 3.8 ± 0.9 years who were undergoing rehabilitation using standard methods. Traditional methods of physical therapy and the methods of the Bobath therapy have a significant effect on the brain venous blood flow. At the same time, the significance of individual methods of physical therapy is not convincing. The comparison of changes in blood flow using the Bobath therapy and traditional methods allowed identifying certain differences. The influence of the Bobath methods, on the first place, concerns the more optimal effect on the blood flow in the veins of the spine and the direct venous sinus. At the same time, changes in blood flow with traditional approaches are more convincing to the effect on blood flow in the internal jugular veins and veins of Rosenthal.

Kinetic Analysis of Unilateral Landings in Female Volleyball Players After a Dynamic and Combined Dynamic-Static Warm-up

Avedesian, JM, Judge, LW, Wang, H, and Dickin, DC. Kinetic analysis of unilateral landings in female volleyball players after a dynamic and combined dynamic-static warm-up. J Strength Cond Res 33(6): 1524-1533, 2019-A warm-up is an important period before training or competition to prepare an athlete for the physical demands of subsequent activity. Previous research has extensively focused on the effects of warm-up in relation to various jumping performance attributes; however, limited research has examined the biomechanical nature of landings after common warm-up practices. Twelve female, collegiate-level volleyball players performed unilateral landings on the dominant and nondominant limb before and after dynamic warm-ups and combined dynamic-static (CDS) warm-ups. Kinetic variables of interest were measured at the hip and knee during the landing phase of a volleyball-simulated jump-landing maneuver. A significant 3-way interaction (warm-up × limb × time) for peak internal knee adduction moment was observed, as this kinetic parameter significantly increased (p = 0.01; d = 0.79) in the nondominant limb at 1-minute post-CDS warm-up. No other warm-up differences were detected; however, significant main effects of limb were determined for dominant-limb internal hip abduction moment (p < 0.01; d = 1.32), dominant-knee internal rotation moment (p < 0.01; d = 1.88), and nondominant-knee external rotation moment (p < 0.01; d = 1.86), which may be due to altered hip and trunk mechanics during the jump landings. This information provides strength and conditioning professionals with biomechanical information to determine warm-up protocols that reduce the risk of injury in female volleyball athletes.