Comparison of effects of training order of explosive strength and plyometrics training on different physical abilities in adolescent handball players.

While both plyometric and traditional resistance training methods are beneficial to athletic performance in a wide range of sports, their efficacy regarding training order has yet to be determined in a periodized training programme. Therefore, this study compared the effects of a 12-week training period where explosive strength training (six weeks) preceded plyometric training (six weeks), or vice versa. Forty-two competitive male (n = 12) and female (n = 30) adolescent handball players (age 14.9 ± 0.5 years, body mass 64.1 ± 9.1 kg, height 1.71 ± 0.09 m) conducted explosive strength training for six weeks followed by six weeks of plyometric training or vice versa. Variables included a 30 m sprint, a change of direction test, countermovement jump (CMJ) with and without arm swing, load-velocity back squat assessment, overhead throwing velocity with and without preliminary steps, and the Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1). Both groups experienced similar improvements in the CMJ, change of direction and load-velocity squat assessments from pre- to posttest (p ≤ 0.013, η 2 = 0.194-0.378). Conversely, no improvements were observed in the Yo-Yo IR1, 30 m sprint or throwing velocity tests, regardless of group (p ≥ 0.081). No main effect of training order was observed for any of the tests employed (p ≥ 0.31). Training order does not appear to play a noticeable role in the physical development of young handball players. Therefore, practitioners could focus on implementing variations in exercise and loading to benefit athlete adherence and correspond to present needs.

Effect of complex training on carbon monoxide, cardiorespiratory function, and body mass among college students at the initial stage of stopping smoking.

[Purpose] This study aimed to analyze the effects of complex training on carbon monoxide, cardiorespiratory function, and body mass among college students with the highest smoking rate among all age group. [Subjects and Methods] A total of 40 college students voluntarily participated in this study. All subjects smoked and were randomly divided into two groups: the experimental group (N=20) and the control group (N=20). The experimental group underwent complex training (30 min of training five times a week for 12 weeks) while the control group did not participate in such training. The complex training consisted of two parts: aerobic exercise (walking and running) and resistance exercise (weight training). [Results] Two-way ANOVA with repeated measures revealed significant interactions among CO, VO2max, HRmax, VEmax, body fat, and skeletal muscle mass, indicating that the changes were significantly different among groups. [Conclusion] A 12 week of complex physical exercise program would be an effective way to support a stop-smoking campaign as it quickly eliminates CO from the body and improves cardiorespiratory function and body condition.

Agility profile in sub-elite under-11 soccer players: is SAQ training adequate to improve sprint, change of direction speed and reactive agility performance?

The purpose of this study was to examine the effects of speed, agility and quickness (SAQ) training on acceleration (5 and 20 m), change of direction speed (CODS) and reactive agility in preadolescent soccer players. Thirty-five participants (age = 10.57 ± 0.26, body mass = 36.78 ± 5.34 kg, body height = 1.42 ± 0.05 m), randomly assigned to experimental (EG, n = 20) and control groups (CG, n = 15), completed a 12-week training intervention, 2 day/week. A significant interaction was found in 5-m sprint (P < 0.05, part η2 = 0.117) and reactive agility (P < 0.01, part η2 = 0.248) between EG and CG. In both groups, 20-m sprint time improved significantly (P < 0.05, effect size = 0.3-0.4) while performance on CODS remained unchanged after 12 weeks. These findings indicated that SAQ training could positively affect cognitive skills and initial sprint acceleration through the middle childhood, offering useful guidance to soccer coaches.

Effect of a 12-week complex training on the body composition and cardiorespiratory system of female college students.

[Purpose] The aim of this study was to examine the effects of a complex exercise program on the body composition and cardiorespiratory system of female college students. [Subjects and Methods] This study included 20 female college students who had not participated in any particular sports in the last 3 months. The complex exercise program consisted of two parts, aerobic exercise and weight training. First, aerobic exercise was implemented (30 min 5 times a week for 12 weeks) according to the participants' exercise tolerance. Second, weight training was implemented (40 min 5 times a week for 12 weeks) with 60% of 1 repetition maximum (RM). [Results] The t-test results showed significant differences in body composition between the before and after the complex exercise program. The subjects' body weights and body fat percentages were decreased, and their skeletal muscle masses were increased. Increased levels of maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) were also observed. [Conclusion] In conclusion, the 12-week complex exercise program, including aerobic and weight training, had positive effects on the body composition and cardiorespiratory system of the female college students.

Acute effect of a complex training protocol of back squats on 30-m sprint times of elite male military athletes.

[Purpose] The aim of this study was to determine the acute effect temporal of a complex training protocol on 30 meter sprint times. A secondary objective was to evaluate the fatigue indexes of military athletes. [Subjects and Methods] Seven military athletes were the subjects of this study. The variables measured were times in 30-meter sprint, and average power and peak power of squats. The intervention session with complex training consisted of 4 sets of 5 repetitions at 30% 1RM + 4 repetitions at 60% 1RM + 3 repetitions of 30 meters with 120-second rests. For the statistical analysis repeated measures of ANOVA was used, and for the post hoc analysis, student's t-test was used. [Results] Times in 30 meter sprints showed a significant reduction between the control set and the four experimental sets, but the average power and peak power of squats did not show significant changes. [Conclusion] The results of the study show the acute positive effect of complex training, over time, in 30-meter sprint by military athletes. This effect is due to the post activation potentiation of the lower limbs' muscles in the 30 meters sprint.

Effect of two complex training protocols of back squats in blood indicators of muscular damage in military athletes.

[Purpose] The aim of this study was to determine the variations in the blood muscular damage indicators post application of two complex training programs for back squats. [Subjects and Methods] Seven military athletes were the subjects of this study. The study had a quasi-experimental cross-over intra-subject design. Two complex training protocols were applied, and the variables to be measured were cortisol, metabolic creatine kinase, and total creatine kinase. For the statistical analysis, Student's t-test was used. [Results] Twenty-four hours post effort, a significant decrease in cortisol level was shown for both protocols; however, the metabolic creatine kinase and total creatine kinase levels showed a significant increase. [Conclusion] Both protocols lowered the indicator of main muscular damage in the blood supply (cortisol). This proved that the work weight did not generate significant muscular damage in the 24-hour post-exercise period.

The effect of a complex training program on skating abilities in ice hockey players.

[Purpose] Little data exist on systemic training programs to improve skating abilities in ice hockey players. The purpose of this study was to evaluate the effectiveness of a complex training program on skating abilities in ice hockey players. [Methods] Ten male ice hockey players (training group) that engaged in 12 weeks of complex training and skating training and ten male players (control group) that only participated in 12 weeks of skating training completed on-ice skating tests including a 5 time 18 meters shuttle, t-test, Rink dash 5 times, and line drill before, during, and the training. [Results] Significant group-by-time interactions were found in all skating ability tests. [Conclusion] The complex training program intervention for 12 weeks improved their skating abilities of the ice hockey players.

The effect of flywheel complex training with eccentric-overload on muscular adaptation in elite female volleyball players.

This study aimed to compare the effects of 8 weeks (24 sessions) between flywheel complex training with eccentric overload and traditional complex training of well-trained volleyball players on muscle adaptation, including hypertrophy, strength, and power variables. Fourteen athletes were recruited and randomly divided into the flywheel complex training with an eccentric-overload group (FCTEO, n = 7) and the control group (the traditional complex training group, TCT, n = 7). Participants performed half-squats using a flywheel device or Smith machine and drop jumps, with three sets of eight repetitions and three sets of 12 repetitions, respectively. The variables assessed included the muscle thickness at the proximal, mid, and distal sections of the quadriceps femoris, maximal half-squats strength (1RM-SS), squat jump (SJ), countermovement jump (CMJ), and three-step approach jump (AJ). In addition, a two-way repeated ANOVA analysis was used to find differences between the two groups and between the two testing times (pre-test vs. post-test). The indicators of the FCTEO group showed a significantly better improvement (p < 0.05) in CMJ (height: ES = 0.648, peak power: ES = 0.750), AJ (height: ES = 0.537, peak power: ES = 0.441), 1RM-SS (ES = 0.671) compared to the TCT group and the muscle thicknes at the mid of the quadriceps femoris (ES = 0.504) after FCTEO training. Since volleyball requires lower limb strength and explosive effort during repeated jumps and spiking, these results suggest that FCTEO affects muscular adaptation in a way that improves performance in well-trained female volleyball players.

Effects of Eccentric Speed during Front Squat Conditioning Activity on Post-activation Performance Enhancement of Hip and Thigh Muscles.

The phenomenon of post-activation performance enhancement plays an unidentified role in movement eccentric speed and individual muscle group responses. Therefore, this study aimed to determine whether the loaded front squat (FSq) speed of the eccentric phase would influence the post-activation performance enhancement effect and whether the FSq would elicit similar performance enhancement of knee flexion, knee extension, hip flexion, and hip extension muscles. Twenty resistance-trained handball players performed the FSq under maximum eccentric-concentric speed and 2-s eccentric speed (only the eccentric phase performed), while pre- and post-front squat countermovement jump, knee, and hip isokinetic flexion/extension performance were tested. The FSq conditioning activity was performed in a single set of three repetitions with either 90% (maximum eccentric-concentric speed) or 120% (2-s eccentric speed) of one repetition maximum, and post-performance was measured 4-12 min after the FSq. Athletes randomly changed the FSq eccentric speed and tested the hip or knee isokinetic flexion/extension strength at 180°/s. ANOVA showed that the rate of force development during the jump increased (Cohen d = 0.59-0.77) with no differences between 2-s eccentric and maximum speed eccentric protocols. Isokinetic strength increased after the 2-s eccentric FSq in hip extension (d = 0.76-0.86), knee flexion (d = 0.74-0.88), and hip flexion (d = 0.82), with no differences in knee extension strength. After maximum eccentric-concentric speed, isokinetic strength increased in hip extension (d = 1.25). In conclusion, the FSq conditioning activity enhances hip extensors' performance more than knee extensors' performance. Different eccentric types of muscle action during a conditioning activity alter the level of local muscle enhancement.

Complex training with blood flow restriction increases power output and bar velocity during half-squat jump: a pilot randomized controlled study.

Purpose: This study examined the effects of 8-week complex training (CT) with blood flow restriction (BFR) on power output and bar velocity. Methods: Twenty-six healthy male university athletes (age: 19.40 ± 0.88 years) completed three sessions of CT with BFR (CT_BFRT, n = 13) or CT-only (i.e., control) (n = 13) per week (i.e., 24 sessions in total). Before and immediately after intervention, participants completed power measurement as assessed by one-repetition maximum (1RM) squat, squat jump (SJ), countermovement jump (CMJ), and mean power (MP), peak power (PP), mean bar velocity (Bar-MV), and peak bar velocity (Bar-PV) during the half-squat jump. Results: Two-way ANOVA models showed significant main effect of time (p < 0.001) but not group (p > 0.89) or interaction (p > 0.37) between group and time on 1RM of the squat, SJ, or CMJ; however, significant interactions were observed in MP (p = 0.03, Cohen's d = 1.39), PP (p = 0.03, Cohen's d = 1.14), Bar-MV (p = 0.049, Cohen's d = 1.26), and Bar-PV (p = 0.01, Cohen's d = 1.56). The post hoc analyses revealed that MP, PP, Bar-MV, and Bar-PV after CT with BFRT were significantly greater compared to all the other three conditions (i.e., pre-CT_BFRT, pre- and post-CT-only). Conclusion: CT with BFR may induce significantly greater improvements in power output and bar velocity during half-squat jump and induce comparable improvements in 1RM of the squat, SJ, and CMJ of males as compared to CT only, suggesting this novel CT with BFR would be a promising strategy to enhance power performance in healthy male university athletes.

Effects of diverse resistance training modalities on performance measures in athletes: a network meta-analysis.

Background: Jumping ability is one of the necessary qualities for athletes. Previous studies have shown that plyometric training and complex training including plyometrics can improve athletes' jumping ability. With the emergence of various types of complex training, there is uncertainty about which training method has the best effect. This study conducted a meta-analysis of randomized controlled trials of plyometric-related training on athletes' jumping ability, to provide some reference for coaches to design training plans. Methods: We systematically searched 3 databases (PubMed, Web of Science, and Scopus) up to July 2023 to identify randomized controlled trials investigating plyometrics related training in athletes. The two researchers conducted literature screening, extraction and quality assessment independently. We performed a network meta-analysis using Stata 16. Results: We analyzed 83 studies and found that complex training, which includes high-intensity intervals and plyometric exercises, was the most effective method for improving squat jumps (SURCA = 96%). In the case of countermovement jumps a combination of electrostimulation and plyometric training yielded the best results (SURCA = 97.6%). Weightlifting training proved to be the most effective for the standing long jump (SURCA = 81.4%), while strength training was found to be the most effective for the five bounces test (SURCA = 87.3%). Conclusion: Our current study shows that complex training performs more efficient overall in plyometric-related training. However, there are different individual differences in the effects of different training on different indicators (e.g., CMJ, SJ, SLJ, 5BT) of athletes. Therefore, in order to ensure that the most appropriate training is selected, it is crucial to accurately assess the physical condition of each athlete before implementation. Clinical Trial Registration: https://www.crd.york.ac.uk/PROSPERO/, Registration and protocol CRD42023456402.

Effects of variable resistance training within complex training on strength and punch performance in elite amateur boxers.

Objectives: This study explored the effects of 6 weeks of variable resistance training (VRT) and constant resistance training (CRT) within complex training, on muscle strength and punch performance. Methods: Twenty-four elite female boxers from the China National team were divided randomly between an experimental group (VRT) and a control group (CRT). Maximum strength of the upper and lower limbs, countermovement jump (CMJ) performance, and punch performance (single, 10s and 30s continuous) were assessed pre- and post- intervention. Results: VRT and CRT showed significant increases (p < 0.001) in the bench press (ES = 1.79 and 1.07, respectively), squat (ES = 1.77 and 1.10, respectively), and CMJ (ES = 1.13 and 0.75, respectively). The bench press (p < 0.05) and squat (p < 0.05) improved significantly more following VRT compared to CRT. Additionally, single punch performance (speed, force, and power) increased significantly in the experimental group (ES = 1.17-1.79) and in the control group (ES = 0.58-1.32), except for the lead punch force in the control group (p > 0.05, ES = 0.20). 10s continuous punch performance (number, speed, force, and power) increased significantly (both p < 0.05) in the experimental group (ES = 0.52-1.65) and in the control group (ES = 0.32-0.81). 30s continuous punch performance (number, force, and power) increased significantly increased significantly (both p < 0.05). However, no statistically significant differences were found between groups for punch performance. Conclusion: These findings provide evidence that VRT may improve maximum muscle strength in both upper and lower limbs, vertical jump and punch performance in elite amateur boxers.

The Impact of Core Complex Training on Some Basketball-Related Aspects of Physical Strength and Shooting Performance.

Exercises for the core can be categorized as promoting core-stability, core-strength, or functionality, as these are crucial aspects of most sports activities. This study aimed to examine the effects of using core complex training (CCT), complex training (CT), and core exercise (CE) on some aspects of muscle strength and shooting performance in basketball players. The 36 participants were divided into three groups of 12 each, and then the experimental approach was applied to each group. The groups were labeled as follows: the core complex training group (N = 12; age, 18.58 ± 0.67 years; height, 178.08 ± 0.79 cm; weight, 76.42 ± 1.38 kg; training age, 7.42 ± 0.51 years); the complex training group (N = 12; age, 18.50 ± 0.52 years; height, 177.92 ± 1.31 cm; weight, 76.67 ± 1.78 kg; training age, 7.33 ± 0.49 years); and the core exercise group (n = 12; age, 18.42 ± 0.52 years; height, 177.75 ± 1.29 cm; weight, 76.58 ± 1.38 kg; training age, 7.42 ± 0.67 years). For ten weeks, each of the three groups participated in three training sessions every week. This study investigates the impact of core complex training on basketball shooting ability and muscle strength. The eight-week program, consisting of weight training, plyometric exercises, and core exercises, yielded improvements in muscle strength and shooting accuracy. In tests of muscular strength and basketball shooting ability, the CCT group outperformed the CE and CT groups. The F value varied from 3.75 to 58.77, which are function values with a p < 0.05 significance level. The core complex training group exhibited superior muscle strength to that of both the complex training group and the core exercise group, in some areas. This is shown in the results of the javelin quadrathlon medicine ball test, the core muscle strength and stability test, the sit-up abdomen test, the sit-up back test, the standing long jump test, the Sargent jump test, and the shooting test (p < 0.005). Due to the effect of the core complex training program on improving performance efficiency and muscle strength, which affects the results of matches, we have recommended using the proven basic strength training program at other age stages, with the objective of including the concept, importance, and design of compound basic strength training in training programs used by basketball coaches.

The Effect of Complex Training on Physical Performance in Rugby League Players.

PURPOSE: To compare the effects of variable-resistance complex training (VRCT) versus traditional complex training (TCT) on strength, power, speed, and leg stiffness (Kleg) in rugby league players during a 6-week mesocycle. METHODS: Twenty-four rugby league players competing in the British University and Colleges Sport Premier North Division were randomized to VRCT (n = 8), TCT (n = 8), or control (CON; n = 8). Experimental groups completed a 6-week lower-body complex training intervention (2×/wk) that involved alternating high-load resistance exercise with plyometric exercise within the same session. The VRCT group performed resistance exercises at 70% of 1-repetition maximum (1RM) + 0% to 23% of 1RM from band resistance with a 90-second intracontrast rest interval, whereas the TCT group performed resistance exercise at 93% of 1RM with a 4-minute intracontrast rest interval. Back-squat 1RM, countermovement jump peak power, reactive strength index, sprint times, and Kleg were assessed pretraining and posttraining. RESULTS: VRCT and TCT significantly improved 1RM back squat, countermovement jump peak power, and 5-m sprint time (all P < .05). VRCT also improved Kleg, whereas TCT improved 10- and 20-m sprint times (all P < .05). Between groups, both VRCT and TCT improved 1RM back squat compared with CON (both P < .001). Additionally, VRCT improved Kleg compared with CON (right leg: P = .016) and TCT improved 20-m sprint time compared with CON (P = .042). CONCLUSIONS: VRCT and TCT can be implemented during the competitive season to improve strength, power, and 5-m sprint time. VRCT may lead to greater improvements in reactive strength index and Kleg, whereas TCT may enhance 10- and 20-m sprint times.

The Effect of Complex Training on Muscle Architecture in Rugby League Players.

PURPOSE: To compare the effects of variable-resistance complex training (VRCT) versus traditional complex training (TCT) on muscle architecture in rugby league players during a 6-week mesocycle. METHODS: Twenty-four rugby league players competing in the British University & Colleges Sport (BUCS) Premier North Division were randomized to VRCT (n = 8), TCT (n = 8), or control (n = 8). Experimental groups completed a 6-week lower-body complex training intervention (2×/wk), which involved alternating high-load resistance exercise with plyometric exercise in the same session. The VRCT group performed resistance exercises at 70% of 1-repetition maximum (1RM) + 0% to 23% of 1RM from band resistance with a 90-second intracontrast rest interval, whereas the TCT group performed resistance exercise at 93% of 1RM with a 4-minute intracontrast rest interval. Muscle thickness (MT), pennation angle, and fascicle length (Lf) were assessed for the vastus lateralis (VL) and gastrocnemius medialis using ultrasound imaging. RESULTS: Both TCT and VRCT groups significantly improved VL MT and VL Lf compared with control (all P < .05). Standardized within-group changes in MT and Lf (Cohen dav ± 95% CI) were moderate for TCT (dav = 0.91 ± 1.0; dav = 1.1 ± 1.1) and unclear for VRCT (dav = 0.44 ± 0.99; dav = 0.47 ± 0.99), respectively. Differences in change scores between TCT and VRCT were unclear. CONCLUSIONS: VRCT and TCT can be utilized during the competitive season to induce favorable MT and Lf muscle architecture adaptations for the VL. TCT may induce greater muscle architecture adaptations of the VL, whereas VRCT may be of more practical value given the shorter intracontrast rest interval between resistance and plyometric exercises.

The Effects of a 10-Week Aerobic and Unilateral Lower Extremity Resistance Training Program on Amplitude and Nerve Conduction Velocity of Sensory and Motor Nerves in Diabetic Patients with Neuropathy.

This study aimed to investigate the effects of 10-week aerobic and unilateral lower extremity resistance training on nerve conduction velocity and amplitude of sensory and motor nerves in diabetic patients with neuropathy. This clinical trial was conducted on twenty women and men (aged 30-60 years old) with diabetic neuropathy. Participants were randomly assigned to one of the two groups: an exercise group (EG; n = 10) and a control group (CG; n = 10). The EG performed a 10-week programme with one session of aerobic exercises (40% to 70% of HR reserve), supplemented with one session of specific lower extremity resistance exercises (60-90 min/day) on the same day for four days per week. The CG subjects performed their regular daily activities. The nerve conduction velocity, amplitude of sensory and motor nerves and glycosylated haemoglobin A1c were measured before and after the intervention. The repeated-measures ANOVA showed a significant increase in the conduction velocity of the sural sensory nerve as well as the peroneal motor nerve (p < 0.01, p < 0.01). The changes in the conduction velocity of the tibial nerve were similar when compared to the control group (p > 0.05). A significantly greater decrease in glycosylated haemoglobin was also observed in the EG group (p < 0.01). Performing 10 weeks of aerobic and specific unilateral lower extremity exercises can improve the function of sensory and motor nerves and improve symptoms in diabetic patients with neuropathy. Given the limited studies in this area, the exact mechanisms of this performance improvement need further examination.

Effect of 12 weeks of complex training on occupational activities, strength, and power in professional firefighters.

Objective: This study examined the effects of 12-week complex training (CT) programs on professional firefighters' occupational activities, strength, and power. Methods: Thirty men professional firefighters were randomly assigned to the CT group (n = 15) and control group (n = 15). The CT group performed complex training and the control group completed resistance training (RT) twice a week over 12 weeks. The occupational activities, strength, and power were assessed at baseline and immediately after the intervention by measuring the performance of 100 m load-bearing run (100 m LR), 60 m shoulder ladder run (60 m SLR), 5 m × 20 m shuttle run (5 m × 20 m SR), 4th-floor climbing rope (4th-floor CR), countermovement jump with arm swing (CMJas), seated medicine-ball throw (SMT), one-repetition maximum bench press (1RM BP), and one-repetition maximum back squat (1RM BS). Results: The results showed that compared to RT, CT induced significantly greater improvements in 60 m SLR (p = 0.007), 4th-floor CR (p = 0.020), CMJas (p = 0.001), and SMT (p < 0.001). Conclusion: These findings suggest that CT is a novel intervention with great promise of improving professional firefighters' occupational activities, strength, and power.

The effects of 8-week complex training on lower-limb strength and power of Chinese elite female modern pentathlon athletes.

Complex training (CT) is a combination training method that alternates between performing high-load resistance training (RT) and plyometric training within one single session. The study aimed to examine the effects of CT on lower-limb strength and power of elite female modern pentathlon athletes under the new modern pentathlon format and competition rules. Ten female participants (age: 23.55 ± 2.22 years, weight: 60.59 ± 3.87 kg, height: 169.44 ± 4.57 cm, and training experience: 6.90 ± 2.08 years) of the national modern pentathlon team completed 8 weeks of RT as followed by 8 weeks of CT, with 2 weeks of break. Then, the participants conducted 8 weeks of CT, which included RT combined with plyometric training (e.g., drop jump and continuous jump). All stages of training were designed by the linear strength training period theories, requiring participants to train twice for the first 4 weeks and three times for the second 4 weeks. The one-repetition maximum (1RM) of squat, isometric mid-thigh pull (IMTP), counter-movement jump (CMJ), squat jump (SJ), pre-stretch augmentation percentage (PSAP), and reaction strength index (RSI) were assessed before and after both RT and CT training. One-way repeated-measure ANOVA models revealed that the 1RM of squat was significantly improved (p < 0.001) after RT as compared to pre-RT. No significant improvement in IMTP (p = 0.055), CMJ (p = 0.194), SJ (p = 0.692), PSAP (p = 0.087), and RSI (p = 0.238) was not observed. After CT, 1RM of squat (p < 0.001), IMTP (p < 0.035), CMJ (p < 0.001), SJ (p < 0.008), RSI (p < 0.006) were significant improved as compared to pre-RT, post-RT and pre-CT, while significant improvements in PSAP were observed as compared to pre-RT (p = 0.003) and pre-CT (p = 0.027), but not to post-RT (p = 0.156). This pilot study showed the promise of CT following RT to improve lower-limb strength and power in elite female modern pentathlon athletes. The findings are worthwhile to be confirmed in future studies with larger sample size and randomized design.

Does caffeine ingestion affect the lower-body post-activation performance enhancement in female volleyball players?

BACKGROUND: Post-activation performance enhancement (PAPE) is a physiological phenomenon that acutely improves voluntary muscular performance following a conditioning activity. A large and growing body of literature has investigated different strategies to induce a PAPE stimulus; however, little attention has been given to whether acute caffeine ingestion could augment the effect of PAPE on subsequent performance. This study evaluated the acute effects of caffeine ingestion and back squat conditioning activity on subsequent countermovement jump (CMJ) performance in female semi-professional volleyball players. METHODS: Fourteen resistance-trained female volleyball players (26 ± 3 years) performed 3 different testing conditions in randomized order: where each ingested 6 mg/kg of caffeine (CAF) or placebo (PLAC) and performed a single set of back squats at 80%1RM until mean movement velocity dropped by 10% as the conditioning activity or a control (CTRL) condition where participants did not ingest any supplement and did not perform the conditioning activity. CMJ height was examined at baseline and in 2 min intervals until 10 min postconditioning activity. Furthermore, due to the wide inter-individual variation in optimal recovery time of PAPE response, the baseline and best post-conditioning activity performance were also analyzed. RESULTS: The Friedman test revealed a significant difference in jump height within CTRL (p = 0.002) and CAF (p = 0.001) conditions, but no significant difference was found within the PAP condition. The post hoc showed a significant decrease in jump height in 8th min in CTRL condition (p = 0.022, effect size [ES] = -0.31), a significant increase in jump height in 2nd min in CAF condition (p = 0.013, ES = 0.3), without differences in PLAC condition in comparison to baseline values. Moreover, a significant jump height increases from baseline to best performance post conditioning activity value for CAF (p = 0.001, ES = 0.39) and PLAC (p = 0.001, ES = 0.3) condition, but no significant difference was found for the CTRL condition. CONCLUSIONS: The single set of heavy-loaded back squats with controlled velocity used as a conditioning activity in the current study enhanced subsequent CMJ performance in female volleyball players with no additional effect of caffeine.

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.