Effects of plyometric jump training in female soccer player's vertical jump height: A systematic review with meta-analysis

Light load jump squat and plyometric training enhance jumping, sprinting, change of direction, and balance performance of male soccer players (U-19): a randomized controlled trial

BACKGROUND

In sports science, optimizing athletic performance is pursued through an emerging approach that combined light-loaded squat (LLS) training and plyometric jump training (PJT), targeting strength, power, and neuromuscular adaptations, particularly beneficial for the dynamic demands of youth soccer. The aim of this study was to examine the effect of a combined LLS training and PJT program on athletic performance and balance in youth soccer players.

METHODS

Thirty-two male players were randomly assigned to two groups: an experimental group (EG: N.=16; age: 18.56±0.51 years; body mass: 66.87±4.99 kg; height: 1.78±0.07 m) and a control group (CG: N.=16; age: 18.68±0.47 years; body mass: 67.93±4.58 kg; height: 1.77±0.07 m) from the same U19 team of a professional club voluntarily participated in the study. Squat jump (SJ), countermovement jump (CMJ), horizontal jump (HJ), drop jump (DJ), 30 m sprint (30 mS), change of direction ability (4×5 m sprint test [S 4×5 m]) and static balance (the stork balance) performance tests were carried out in the week before and the week after the 8 weeks with combined LLS and PJT period. The two-way analysis of variance (ANOVA) was used for all tests.

RESULTS

The results of this study show that the EG had significantly greater improvements than the CG in all tests (all P<0.001). Also, EG experienced higher performance between preintervention and post intervention measures (all P<0.05). There was no significant difference between the two groups in the 4×5mS performance (P>0.05).

CONCLUSIONS

We conclude that coaches may be advised to use the combined LLS and PJT since it is as effective as traditional methods and perfect for sports and activities requiring fast, explosive movements during the in-season period than regular training.

Improving the estimation of countermovement jump height from force plate recordings by considering the interaction between multiple procedural steps: An optimisation approach

Force plates are used as standalone measurement systems in research and practice to evaluate metrics such as jump height. Calculating jump height involves multiple procedural steps, but previous investigations aiming to improve calculation procedures have only considered the influence of a single procedural step in isolation. The purpose of this study was to investigate if considering the interacting influence of multiple procedural steps in conjunction would impact the accuracy of jump height calculated from force plate recordings. An optimisation procedure was used to determine the combination of filter type, filter order, filter cut-off, integration start point and instant of take-off, that would minimize the root mean squared difference between force plate calculated jump height and a kinematic criterion. The best filter approach was a fifth order Butterworth filter with a 6 Hz cut-off frequency or a third order Chebyshev filter with a 5 Hz cut-off frequency. The best starting point for integration was approximately 0.25 s prior to the onset of the jump and the instant of take-off was best identified by finding the first instant that the force-time signal decreased by the magnitude of system weight. The presented optimisation technique provides an improved quantitative approach to develop standard procedures.

Strength and conditioning in dance: A systematic review and meta-analysis

To assess the evidence for the effect of strength and conditioning on physical qualities and aesthetic competence in dance populations, three electronic databases (PubMed, Scopus, SPORTDiscus) were searched (until September 2022) for studies that met the following criteria: (i) dancers aged >16 years; (ii) structured strength and conditioning intervention; and (iii) with physical qualities and aesthetic competence as outcome measures. Methodological quality and risk of bias of the included studies were assessed through the systematic review tool "QualSyst". Meta-analyses of effect sizes (Hedges' g) with forest plots explored the effects of the strength and conditioning interventions. Thirty-six studies met the inclusion criteria and were included in this review. Meta-analysis indicated strength and conditioning significantly (p < 0.05) improved lower body power (g = 0.90, 95% CI: 0.53-1.27), upper body strength (g = 0.98, 95% CI: 0.39-1.57), lower body strength (g = 1.59, 95% CI: 0.97-2.22), and flexibility (g = 0.86, 95% CI: 0.05-1.66). Strength and conditioning interventions were found to be effective at improving physical qualities in dancers, recommending their participation in additional sessions to enhance overall fitness and ultimately dance performance. It is recommended that future strength and conditioning intervention research should include sample size calculations, with participants recruited from a specific dance genre and skill level in order to evaluate how strength and conditioning influences dance performance.

Plyometric Jump Training Effects on Maximal Strength in Soccer Players: A Systematic Review with Meta-analysis of Randomized-Controlled Studies

BACKGROUND

Maximal strength may contribute to soccer players' performance. Several resistance training modalities offer the potential to improve maximal strength. During recent years, a large number of plyometric jump training (PJT) studies showed evidence for maximal strength improvements in soccer players. However, a comprehensive summary of the available data is lacking.

OBJECTIVE

To examine the effects of PJT compared with active, passive or intervention controls on the maximal strength of soccer players, irrespective of age, sex or competitive level.

METHODS

To perform a systematic review with meta-analysis following PRISMA 2020. Three electronic databases (PubMed, Web of Science, and SCOPUS) were systematically searched. Studies published from inception until March 2023 were included. A PICOS approach was used to rate studies for eligibility. The PEDro scale was used to assess risk of bias. Meta-analyses were performed using the DerSimonian and Laird random-effects model if ≥ 3 studies were available. Moderator and sensitivity analyses were performed, and meta-regression was conducted when ≥ 10 studies were available for a given comparison. We rated the certainty of evidence using GRADE.

RESULTS

The search identified 13,029 documents, and from these 30 studies were eligible for the systematic review, and 27 for the meta-analyses. Overall, 1,274 soccer players aged 10.7-25.0 years participated in the included studies. Only one study recruited females. The PJT interventions lasted between 5 and 40 weeks (median = 8 weeks), with 1-3 weekly sessions. Compared to controls, PJT improved maximal dynamic strength (18 studies, 632 participants [7 females], aged 12.7-24.5 y; effect size [ES] = 0.43, 95% confidence interval [CI] = 0.08-0.78, p = 0.017, impact of statistical heterogeneity [I2] = 77.9%), isometric strength (7 studies; 245 participants, males, aged 11.1-22.5 y; ES = 0.58, 95% CI = 0.28-0.87, p < 0.001, I2 = 17.7%), and isokinetic peak torque (5 studies; 183 participants, males, aged 12.6-25.0 y; ES = 0.51, 95% CI = 0.22-0.80, p = 0.001, I2 = 0.0%). The PJT-induced maximal dynamic strength changes were independent of participants' age (median = 18.0 y), weeks of intervention (median = 8 weeks), and total number of training sessions (median = 16 sessions). The certainty of evidence was considered low to very low for the main analyses.

CONCLUSIONS

Interventions involving PJT are more effective to improve maximal strength in soccer players compared to control conditions involving traditional sport-specific training. Trial Registration The trial registration protocol was published on the Open Science Framework (OSF) platform in December 2022, with the following links to the project ( https://osf.io/rpxjk ) and to the registration ( https://osf.io/3ruyj ).

Exploring the Effect of Acute and Regular Physical Exercise on Circulating Brain-Derived Neurotrophic Factor Levels in Individuals with Obesity: A Comprehensive Systematic Review and Meta-Analysis

Obesity is a major global health concern linked to cognitive impairment and neurological disorders. Circulating brain-derived neurotrophic factor (BDNF), a protein crucial for neuronal growth and survival, plays a vital role in brain function and plasticity. Notably, obese individuals tend to exhibit lower BDNF levels, potentially contributing to cognitive decline. Physical exercise offers health benefits, including improved circulating BDNF levels and cognitive function, but the specific impacts of acute versus regular exercise on circulating BDNF levels in obesity are unclear. Understanding this can guide interventions to enhance brain health and counter potential cognitive decline in obese individuals. Therefore, this study aimed to explore the impact of acute and regular physical exercise on circulating BDNF in individuals with obesity. The target population comprised individuals classified as overweight or obese, encompassing both acute and chronic protocols involving all training methods. A comprehensive search was conducted across computerized databases, including PubMed, Academic Search Complete, and Web of Science, in August 2022, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Initially, 98 studies were identified, from which 16 studies, comprising 23 trials, met the selection criteria. Substantial heterogeneity was observed for both acute (I2 = 80.4%) and long-term effects (I2 = 88.7%), but low risk of bias for the included studies. A single session of exercise increased circulating BDNF levels among obese patients compared to the control group (ES = 1.25, 95% CI = 0.19 to 2.30, p = 0.021). However, with extended periods of physical exercise, there was no significant increase in circulating BDNF levels when compared to the control group (ES = 0.49, 95% CI = -0.08 to 1.06, p = 0.089). These findings highlight the need to consider exercise duration and type when studying neurobiological responses in obesity and exercise research. The study's results have implications for exercise prescription in obesity management and highlight the need for tailored interventions to optimize neurotrophic responses. Future research should focus on elucidating the adaptive mechanisms and exploring novel strategies to enhance BDNF modulation through exercise in this population. However, further research is needed considering limitations such as the potential age-related confounding effects due to diverse participant ages, lack of sex-specific analyses, and insufficient exploration of how specific exercise parameters (e.g., duration, intensity, type) impact circulating BDNF.

The Effects of Strength, Plyometric and Combined Training on Strength, Power and Speed Characteristics in High-Level, Highly Trained Male Youth Soccer Players: A Systematic Review and Meta-Analysis

BACKGROUND

Male youth soccer players competing at a high level will typically engage in large volumes of soccer training from a young age. However, it is not known whether the high levels of habitual training that these high-performing players are exposed to limit their ability to respond to strength, plyometric or combined training interventions.

OBJECTIVE

The primary aim of our systematic review and meta-analysis was to compare the specific effects of strength, plyometric and combined training with active controls (standard soccer training) on the strength, power and speed characteristics of high-level, highly trained young male soccer players.

METHODS

We performed a literature search across PubMed, Scopus, CINAHL, Web of Science and SPORTDiscus to identify controlled studies that implemented strength, plyometric or combined training in high-level male youth soccer players. Participants were defined as high level or highly trained based on established guidelines related to either competition level or age-related weekly hours spent in soccer training. Studies needed to report at least one outcome of lower body strength, squat jump, countermovement jump, horizontal power, acceleration (0-10 m), speed (15-40 m) or change of direction speed. A meta-analysis was then performed using a random-effects model to determine the magnitude (Hedge's g) of training responses and whether effects differed across modes of training.

RESULTS

From an initial return of 5464 papers, n = 34 studies met the inclusion criteria and provided a total sample of n = 1396 high-level male youth soccer players. Strength, plyometric and combined training resulted in improvements in strength, squat and countermovement jump, horizontal power, acceleration, change of direction speed (all p < 0.05; g = 0.73-1.08, moderate) and speed (p < 0.05; g = 0.40-0.59, small). Lower body strength was the only outcome where training mode had a significant effect (p < 0.05), with plyometric training producing small effects (g = 0.27, p < 0.05) compared with moderate effects for strength (g = 1.07, p < 0.05) and combined (g = 0.75, p < 0.05) training. Prediction intervals for overall effects (all training modes combined) showed that the greatest confidence that future training will lead to positive effects was in the squat and countermovement jump, horizontal power and acceleration (prediction intervals = 0.03-1.81).

CONCLUSIONS

High-level, highly trained male youth soccer players can experience positive gains in indices of strength, power and speed from strength, plyometric and combined training, and the magnitude of gains are mostly similar across modes of training. Based on prediction intervals, there is a good level of certainty that future strength, plyometric and combined training in this population would lead to positive improvements in vertical and horizontal power and sprint acceleration.

Effect of Different Nonstarter Compensatory Strategies on Training Load in Female Soccer Players: A Pilot Study

BACKGROUND

In soccer, the day of the week with the highest external load is match day (MD), with starters (>60 minutes per match) showing higher levels of physical fitness and seasonal high-intensity loading. It is necessary, therefore, to determine training strategies to reduce the differences between starters and nonstarters. The aim of this study was to analyze and compare the external load of different training compensatory strategies with match external load in female nonstarters.

HYPOTHESIS

A strategy combining small-sided games (SSG) and running-based drills (RBD) would reproduce match demands, with RBD leading to greater high-intensity running and SSG leading to a greater number of accelerations and decelerations.

STUDY DESIGN

Descriptive and comparative study.

LEVEL OF EVIDENCE

Level 4.

METHODS

The training and match external load of 14 female players belonging to the same reserve squad of a Spanish First Division Club (Liga Reto Iberdrola) was registered. In the first session after the match (MD+1), nonstarters (<60 minutes in the match) performed 1 of 3 different compensatory strategies: RBD, SSG, or a mixed intervention combining the previous strategies (RBD+SSG). Starters carried out a recovery session.

RESULTS

A marked difference in load was observed between the compensatory training strategies and MD. In comparison with MD, RBD showed greater high-intensity and sprint distances and lower acceleration, SSG showed less high-intensity running and sprint distances, lower peak velocity, and greater acceleration, and RBD+SSG registered lower accelerations. In addition, nonstarters covered greater high-intensity running and sprint distances in RBD and achieved higher accelerations in SSG.

CONCLUSION

RBD and SSG compensatory strategies could be recommended to nonstarter female soccer players in MD+1 to compensate for match external load deficits.

CLINICAL RELEVANCE

This study provides comprehensive information on the compensatory exercises of female soccer players, which can be useful for strength and conditioning coaches when developing recovery strategies during a microcycle.

Effects of Upper-Body Plyometric Training on Physical Fitness in Healthy Youth and Young Adult Participants: A Systematic Review with Meta-Analysis

BACKGROUND

Upper-body plyometric training (UBPT) is a commonly used training method, yet its effects on physical fitness are inconsistent and there is a lack of comprehensive reviews on the topic.

OBJECTIVE

To examine the effects of UBPT on physical fitness in healthy youth and young adult participants compared to active, specific-active, and passive controls.

METHODS

This systematic review followed PRISMA 2020 guidelines and utilized the PICOS framework. PubMed, WOS, and SCOPUS were searched. Studies were assessed for eligibility using the PICOS framework. The effects of UBPT on upper-body physical fitness were assessed, including maximal strength, medicine ball throw performance, sport-specific throwing performance, and upper limb muscle volume. The risk of bias was evaluated using the PEDro scale. Means and standard deviations were used to calculate effect sizes, and the I2 statistic was used to assess heterogeneity. Publication bias was assessed using the extended Egger's test. Certainty of evidence was rated using the GRADE scale. Additional analyses included sensitivity analyses and adverse effects.

RESULTS

Thirty-five studies were included in the systematic review and 30 studies in meta-analyses, involving 1412 male and female participants from various sport-fitness backgrounds. Training duration ranged from 4 to 16 weeks. Compared to controls, UBPT improved maximal strength (small ES = 0.39 95% CI = 0.15-0.63, p = 0.002, I2 = 29.7%), medicine ball throw performance (moderate ES = 0.64, 95% CI = 0.43-0.85, p < 0.001, I2 = 46.3%), sport-specific throwing performance (small ES = 0.55, 95% CI = 0.25-0.86, p < 0.001, I2 = 36.8%), and upper limbs muscle volume (moderate ES = 0.64, 95% CI = 0.20-1.08, p = 0.005, I2 = 0.0%). The GRADE analyses provided low or very low certainty for the recommendation of UBPT for improving physical fitness in healthy participants. One study reported one participant with an injury due to UBPT. The other 34 included studies provided no report measure for adverse effects linked to UBPT.

CONCLUSIONS

UBPT interventions may enhance physical fitness in healthy youth and young adult individuals compared to control conditions. However, the certainty of evidence for these recommendations is low or very low. Further research is needed to establish the optimal dose of UBPT and to determine its effect on female participants and its transfer to other upper-body dominated sports.

Effects of physical training programs on female tennis players' performance: a systematic review and meta-analysis

Background: Tennis is among the world's most popular and well-studied sports. Physical training has commonly been used as an intervention among athletes. However, a comprehensive review of the literature on the effects of physical training programs on female tennis players' performance is lacking. Therefore, this systematic review and meta-analysis aimed to determine the effects of physical training on performance outcomes in female tennis players. Methods: A comprehensive search was conducted on Web of Science, PubMed, SPORTDicus, Scopus, and CNKI from inception until July 2023 to select relevant articles from the accessible literature. Only controlled trials were included if they examined the effects of physical training on at least one measure of tennis-specific performance in female tennis players. The Cochrane RoB tool was employed to assess the risk of bias. The CERT scale was used to examine the quality of program information. The GRADE approach was adopted to evaluate the overall quality of the evidence. The Comprehensive Meta-Analysis software was used for the meta-analysis. Results: Nine studies were selected for the systematic review and seven for the meta-analysis, totaling 222 individuals. The study's exercise programs lasted 6-36 weeks, with training sessions ranging from 30 to 80 min, conducted one to five times per week. Muscle power (ES = 0.72; p = 0.003), muscle strength (ES = 0.65; p = 0.002), agility (ES = 0.69; p = 0.002), serve velocity (ES = 0.72; p = 0.013), and serve accuracy (ES = 1.14; p = 0.002) demonstrated significant improvement following physical training, while no notable changes in linear sprint speed (ES = 0.63; p = 0.07) were detected. Conclusion: Although research on physical training in sports is diversified, studies on training interventions among female tennis players are scarce. This review found that existing training programs yield some favorable outcomes for female tennis players. However, further research with high methodological quality is warranted on the tailoring of specific training programs for female tennis players. There should be more consistent measuring and reporting of data to facilitate meaningful data pooling for future meta-analyses.

Plyometric Jump Training Exercise Optimization for Maximizing Human Performance: A Systematic Scoping Review and Identification of Gaps in the Existing Literature

BACKGROUND

Plyometric jump training (PJT) encompasses a range of different exercises that may offer advantages over other training methods to improve human physical capabilities (HPC). However, no systematic scoping review has analyzed either the role of the type of PJT exercise as an independent prescription variable or the gaps in the literature regarding PJT exercises to maximize HPC.

OBJECTIVE

This systematic scoping review aims to summarize the published scientific literature and its gaps related to HPC adaptations (e.g., jumping) to PJT, focusing on the role of the type of PJT exercise as an independent prescription variable.

METHODS

Computerized literature searches were conducted in the PubMed, Web of Science, and SCOPUS electronic databases. Design (PICOS) framework: (P) Healthy participants of any age, sex, fitness level, or sports background; (I) Chronic interventions exclusively using any form of PJT exercise type (e.g., vertical, unilateral). Multimodal interventions (e.g., PJT + heavy load resistance training) will be considered only if studies included two experimental groups under the same multimodal intervention, with the only difference between groups being the type of PJT exercise. (C) Comparators include PJT exercises with different modes (e.g., vertical vs. horizontal; vertical vs. horizontal combined with vertical); (O) Considered outcomes (but not limited to): physiological, biomechanical, biochemical, psychological, performance-related outcomes/adaptations, or data on injury risk (from prevention-focused studies); (S) Single- or multi-arm, randomized (parallel, crossover, cluster, other) or non-randomized.

RESULTS

Through database searching, 10,546 records were initially identified, and 69 studies (154 study groups) were included in the qualitative synthesis. The DJ (counter, bounce, weighted, and modified) was the most studied type of jump, included in 43 study groups, followed by the CMJ (standard CMJ or modified) in 19 study groups, and the SJ (standard SJ or modified) in 17 study groups. Strength and vertical jump were the most analyzed HPC outcomes in 38 and 54 studies, respectively. The effects of vertical PJT versus horizontal PJT on different HPC were compared in 21 studies. The effects of bounce DJ versus counter DJ (or DJ from different box heights) on different HPC were compared in 26 studies.

CONCLUSIONS

Although 69 studies analyzed the effects of PJT exercise type on different HPC, several gaps were identified in the literature. Indeed, the potential effect of the PJT exercise type on a considerable number of HPC outcomes (e.g., aerobic capacity, flexibility, asymmetries) are virtually unexplored. Future studies are needed, including greater number of participants, particularly in groups of females, senior athletes, and youths according to maturity. Moreover, long-term (e.g., >12 weeks) PJT interventions are needed.

The Effects of a 6-Week Unilateral Strength and Ballistic Jump Training Program on the Force-Velocity Profiles of Sprinting

ABSTRACT

Bettariga, F, Maestroni, L, Martorelli, L, Turner, A, and Bishop, C. The effects of a 6-week unilateral strength and ballistic jump training program on the force-velocity profiles of sprinting. J Strength Cond Res 37(7): 1390-1396, 2023-The aims of this study were (a) to investigate the effects of a unilateral training program, compared with a control group, on a force-velocity (F-V) profile in soccer players and (b) to explore such effects on linear speed. Twenty-four soccer players, randomly assigned to a 6-week unilateral strength and ballistic jump training (UNI) ( n = 12) or a control group (CON) ( n = 12), performed 30-meter linear sprint test. Findings showed small-to-moderate improvements ( p < 0.05) in linear speed time ( g = 0.66-0.81) and in most F-V variables: maximal running velocity ( V0 ) ( g = 0 .81), maximal power output ( Pmax ) ( g = 0.49), maximal ratio of force ( RFmax ) ( g = 0.55), optimal velocity ( Vopt ) ( g = 0.83), and maximal speed ( g = 0.84) from pre- to post-intervention in the UNI group, whereas no meaningful changes were found in the CON group. The between-group comparison indicated small to large significant changes in V0 ( g = 0.95), RFmax ( g = 0.48), Vopt ( g = 0.95), maximal speed ( g = 0.98), and linear speed time performance ( g = 0.42-1.02), with the exception of the 0-5 meter distance, in favor of the UNI group. Thus, a unilateral strength and ballistic jump training program can be used to improve the F-V profile and linear speed performance of amateur soccer players.

Effects of a 4-week plyometric training on activity patterns during different phases of one-leg drop jump with focus on jump height

Athletic women have shown a higher risk of ACL injury during jump landing compared to men. Plyometric training can be an alternative way to minimize the risk of knee injuries via the changed muscle activity patterns. Hence, the aim of this study was to determine the effects of a 4-week plyometric training program on the muscle activity pattern in different phases of one-leg drop jump in active girls. Active girls were randomly allocated into 2 groups (Plyometric training = 10, Control group = 10) where the plyometric training group (PTG) performed 60 min exercises, 2 sessions/1 week for 4 weeks while the control group (CG) had their daily activity. In the pre to post test, the sEMG was recorded from the Rectus Femoris (RF), Biceps Femoris (BF), Medial Gastrocnemius (GaM), and Tibialis Anterior (TA) muscles of the dominant leg during the Preparatory phase (PP), Contact Phase (CP), Flight Phase (FP) of one-leg drop jump. Electromyography variables (Signal amplitude, Maximum activity, Time to peak (TTP), Onset and activity time and Order muscle activity) and Ergo jump variables (Time of preparatory phase (TPP), Time of contact phase (TCP), Time of flight (jump height) phase (TFP), and Explosive power were analyzed. The Univariate ANCOVA test showed a significant difference between the two groups in Activity Time, whilst adjusting for pre-test as a Covariate, only in TA muscle (F_(1,17) = 5.09, p = 0.038, η² = 0.230). In PTG. TA (- 15%), GaM (- 19%), and BF muscles (- 9%) started their activity earlier while there was no significant difference between the two groups at the Onset time. TTP of RF was significantly different between the 2 groups only in the PR phase (0.216 ± 0.07 vs 0.153 ± 0.09 s) (p = 0.049, 95% CI = 0.001, 0.127). Results of the present study suggest that a 4-week plyometric training can improve the stability of leg joints via earlier recruitment of muscles and change activity patterns in lower limb muscles. It also recommends that the preparatory phase before landing be considered an important stage in preventing sports injuries in a training program.

Plyometric-Jump Training Effects on Physical Fitness and Sport-Specific Performance According to Maturity: A Systematic Review with Meta-analysis

BACKGROUND

Among youth, plyometric-jump training (PJT) may provide a safe, accessible, and time-efficient training method. Less is known on PJT effectiveness according to the maturity status.

OBJECTIVE

This systematic review with meta-analysis set out to analyse the body of peer-reviewed articles assessing the effects of PJT on measures of physical fitness [i.e., maximal dynamic strength; change of direction (COD) speed; linear sprint speed; horizontal and vertical jump performance; reactive strength index] and sport-specific performance (i.e., soccer ball kicking and dribbling velocity) according to the participants' maturity status.

METHODS

Systematic searches were conducted in three electronic databases using the following inclusion criteria: (i) Population: healthy participants aged < 18 years; (ii) Intervention: PJT program including unilateral and/or bilateral jumps; (iii) Comparator: groups of different maturity status with control groups; (iv) Outcomes: at least one measure of physical fitness and/or sport-specific performance before and after PJT; (v) experimental design with an active or passive control group, and two or more maturity groups exposed to the same PJT. The DerSimonian and Laird random-effects models were used to compute the meta-analysis. The methodological quality of the studies was assessed using the PEDro checklist. GRADE was applied to assess certainty of evidence.

RESULTS

From 11,028 initially identified studies across three electronic databases, 11 studies were finally eligible to be meta-analysed (n total = 744; seven studies recruited males; four studies recruited females). Three studies were rated as high quality (6 points), and eight studies were of moderate quality (5 points). Seven studies reported the maturity status using age at peak height velocity (PHV; pre-PHV values up to - 2.3; post-PHV up to 2.5). Another four studies used Tanner staging (from Tanner I to V). The training programmes ranged from 4 to 36 weeks, using 1-3 weekly training sessions. When compared to controls, pre-PHV and post-PHV participants obtained small-to-moderate improvements (ES = 0.35 - 0.80, all p < 0.05) in most outcomes (i.e., sport-specific performance; maximal dynamic strength; linear sprint; horizontal jump; reactive strength index) after PJT. The contrast of pre-PHV with post-PHV youth revealed that PJT was similarly effective in both maturity groups, in most outcome measures except for COD speed (in favour of pre-PHV). PJT induces similar physical fitness and sport-specific performance benefits in males and females, with a minimal exercise dosage of 4 weeks (8 intervention sessions), and 92 weekly jumps. Results of this meta-analysis are based on low study heterogeneity, and low to very low certainty of evidence (GRADE analysis) for all outcomes.

CONCLUSION

Compared to control participants, PJT resulted in improved maximal dynamic strength, linear sprint speed, horizontal jump performance, reactive strength index, and sport-specific performance (i.e., soccer ball kicking and dribbling velocity). These effects seem to occur independently of the maturity status, as both pre-PHV and post-PHV participants achieved similar improvements after PJT interventions for most outcomes. However, several methodological issues (e.g., low sample sizes and the pooling of maturity categories) preclude the attainment of more robust recommendations at the current time. To address this issue, consistency in maturity status reporting strategies must be improved in future studies with the general youth population and youth athletes.

Effects of Plyometric Jump Training on the Reactive Strength Index in Healthy Individuals Across the Lifespan: A Systematic Review with Meta-analysis

BACKGROUND

The reactive strength index (RSI) is meaningfully associated with independent markers of athletic (e.g., linear sprint speed) and neuromuscular performance [e.g., stretch-shortening cycle (SSC)]. Plyometric jump training (PJT) is particularly suitable to improve the RSI due to exercises performed in the SSC. However, no literature review has attempted to meta-analyse the large number of studies regarding the potential effects of PJT on the RSI in healthy individuals across the lifespan.

OBJECTIVE

The aim of this systematic review with meta-analysis was to examine the effects of PJT on the RSI of healthy individuals across the lifespan compared with active/specific-active controls.

METHODS

Three electronic databases (PubMed, Scopus, Web of Science) were searched up to May 2022. According to the PICOS approach, the eligibility criteria were: (1) healthy participants, (2) PJT interventions of ≥ 3 weeks, (3) active (e.g., athletes involved in standard training) and specific-active (e.g., individuals using heavy resistance training) control group(s), (4) a measure of jump-based RSI pre-post training, and (5) controlled studies with multi-groups in randomised and non-randomised designs. The Physiotherapy Evidence Database (PEDro) scale was used to assess the risk of bias. The random-effects model was used to compute the meta-analyses, reporting Hedges' g effect sizes (ES) with 95% confidence intervals (95% CIs). Statistical significance was set at p ≤ 0.05. Subgroup analyses were performed (chronological age; PJT duration, frequency, number of sessions, total number of jumps; randomization). A meta-regression was conducted to verify if PJT frequency, duration, and total number of sessions predicted the effects of PJT on the RSI. Certainty or confidence in the body of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Potential adverse health effects derived from PJT were researched and reported.

RESULTS

Sixty-one articles were meta-analysed, with a median PEDro score of 6.0, a low risk of bias and good methodological quality, comprising 2576 participants with an age range of 8.1-73.1 years (males, ~ 78%; aged under 18 years, ~ 60%); 42 studies included participants with a sport background (e.g., soccer, runners). The PJT duration ranged from 4 to 96 weeks, with one to three weekly exercise sessions. The RSI testing protocols involved the use of contact mats (n = 42) and force platforms (n = 19). Most studies reported RSI as mm/ms (n = 25 studies) from drop jump analysis (n = 47 studies). In general, PJT groups improved RSI compared to controls: ES = 0.54, 95% CI 0.46-0.62, p < 0.001. Training-induced RSI changes were greater (p = 0.023) for adults [i.e., age ≥ 18 years (group mean)] compared with youth. PJT was more effective with a duration of > 7 weeks versus ≤ 7 weeks, > 14 total PJT sessions versus ≤ 14 sessions, and three weekly sessions versus < three sessions (p = 0.027-0.060). Similar RSI improvements were noted after ≤ 1080 versus > 1080 total jumps, and for non-randomised versus randomised studies. Heterogeneity (I²) was low (0.0-22.2%) in nine analyses and moderate in three analyses (29.1-58.1%). According to the meta-regression, none of the analysed training variables explained the effects of PJT on RSI (p = 0.714-0.984, R² = 0.0). The certainty of the evidence was moderate for the main analysis, and low-to-moderate across the moderator analyses. Most studies did not report soreness, pain, injury or related adverse effects related to PJT.

CONCLUSIONS

The effects of PJT on the RSI were greater compared with active/specific-active controls, including traditional sport-specific training as well as alternative training interventions (e.g., high-load slow-speed resistance training). This conclusion is derived from 61 articles with low risk of bias (good methodological quality), low heterogeneity, and moderate certainty of evidence, comprising 2576 participants. PJT-related improvements on RSI were greater for adults versus youths, after > 7 training weeks versus ≤ 7 weeks, with > 14 total PJT versus ≤ 14 sessions, and with three versus < three weekly sessions.

A Systematic Review with Meta-Analysis on the Effects of Plyometric-Jump Training on the Physical Fitness of Combat Sport Athletes

We aimed to assess the athletic performance changes in combat sport athletes (CoSAs) after plyometric-jump training (PJT), compared to control conditions, through a systematic review with meta-analysis. Following PRISMA guidelines, three electronic databases were searched for includable articles, according to a PICOS approach. Using a random-effects model, Hedges' g effects sizes (ES) were calculated. Heterogeneity was assessed using the I² statistic, with values of <25%, 25-75%, and >75% representing low, moderate, and high levels of heterogeneity, respectively. Statistical significance was set at p ≤ 0.05. The certainty of evidence was assessed using the GRADE approach. Twelve eligible articles were identified for systematic review, seven of high quality and five of moderate quality, according to the PEDro scale. The studies recruited taekwondo, silat, wrestling, judo, fencing, and karate athletes (292 total participants), including specific-active and active controls. Most participants had a mean age of <18 years and were males (n = 225). Compared to the control, PJT programmes, involving 4-12 weeks and 2-3 sessions per week, induced small to moderate improvements (ES = 0.47 to 1.04) in athletes' maximal strength (e.g., 1RM squat), vertical jump height, change-of-direction speed, and specific performance (e.g., fencing movement velocity), although without meaningful effects on body mass, fat mass, and muscle mass (ES = 0.02 to -0.06). Most (7 of 8) outcomes attained low heterogeneity. The outcome-level GRADE analysis indicated a certainty of evidence from low to moderate. In conclusion, PJT, when compared to control conditions, may improve CoSA athletic performance.

Effects of Plyometric Training on Physical Performance: An Umbrella Review

BACKGROUND

Plyometric training can be performed through many types of exercises involving the stretch-shortening cycle in lower limbs. In the last decades, a high number of studies have investigated the effects of plyometric training on several outcomes in different populations.

OBJECTIVES

To systematically review, summarize the findings, and access the quality of published meta-analyses investigating the effects of plyometric training on physical performance.

DESIGN

Systematic umbrella review of meta-analyses.

DATA SOURCES

Meta-analyses were identified using a systematic literature search in the databases PubMed/MEDLINE, Scopus, SPORTDiscus, Web of Science, Cochrane Library and Scielo.

ELIGIBILITY CRITERIA FOR SELECTING META-ANALYSES

Meta-analyses that examined the effects of plyometric training on physical fitness in different populations, age groups, and sex.

RESULTS

Twenty-nine meta-analyses with moderate-to-high methodological quality were included in this umbrella review. We identified a relevant weakness in the current literature, in which five meta-analyses included control group comparisons, while 24 included pre-to-post-effect sizes. Trivial-to-large effects were found considering the effects of plyometric training on physical performance for healthy individuals, medium-trivial effects for the sports athletes' groups and medium effects for different sports athletes' groups, age groups, and physical performance.

CONCLUSION

The available evidence indicates that plyometric training improves most related physical fitness parameters and sports performance. However, it is important to outline that most meta-analyses included papers lacking a control condition. As such, the results should be interpreted with caution. PROSPERO number: CRD42020217918.

Effects of Combined Upper and Lower Limb Plyometric Training Interventions on Physical Fitness in Athletes: A Systematic Review with Meta-Analysis

Objective: We aimed to meta-analyze the effects of combined upper and lower limb plyometric training (ULLPT) on physical fitness attributes in athletes. Methods: A systematic literature search was conducted in Web of Science, SPORTDiscus, PubMed, and SCOPUS, for up to 13 August 2022. Controlled studies with baseline and follow-up measures were included if they examined the effects of ULLPT on at least one measure of physical fitness indices in athletes. A random effects meta-analysis was performed using the Comprehensive Meta-Analysis software. Results: Fifteen moderate-to-high-quality studies with 523 participants aged 12−22.4 years were included in the analyses. Small to large (ES = 0.42−1.66; p = 0.004 to <0.001) effects were noted for upper and lower body muscle power, linear sprint speed, upper and lower body muscle strength, agility, and flexibility, while no significant effects on static and dynamic balance were noted (ES = 0.44−0.10; all p > 0.05). Athletes’ sex, age, and training program variables had no modulator role on the effects of ULLPT in available data sets. Conclusions: ULLPT induces distinct neuro-muscular adaptations in the upper and lower body musculature and is an efficient method for enhancing athletes’ physical fitness.

Effects of Plyometric Jump Training on Measures of Physical Fitness and Sport-Specific Performance of Water Sports Athletes: A Systematic Review with Meta-analysis

Background

A growing body of literature is available regarding the effects of plyometric jump training (PJT) on measures of physical fitness (PF) and sport-specific performance (SSP) in-water sports athletes (WSA, i.e. those competing in sports that are practiced on [e.g. rowing] or in [e.g. swimming; water polo] water). Indeed, incoherent findings have been observed across individual studies making it difficult to provide the scientific community and coaches with consistent evidence. As such, a comprehensive systematic literature search should be conducted to clarify the existent evidence, identify the major gaps in the literature, and offer recommendations for future studies.

Aim

To examine the effects of PJT compared with active/specific-active controls on the PF (one-repetition maximum back squat strength, squat jump height, countermovement jump height, horizontal jump distance, body mass, fat mass, thigh girth) and SSP (in-water vertical jump, in-water agility, time trial) outcomes in WSA, through a systematic review with meta-analysis of randomized and non-randomized controlled studies.

Methods

The electronic databases PubMed, Scopus, and Web of Science were searched up to January 2022. According to the PICOS approach, the eligibility criteria were: (population) healthy WSA; (intervention) PJT interventions involving unilateral and/or bilateral jumps, and a minimal duration of ≥ 3 weeks; (comparator) active (i.e. standard sports training) or specific-active (i.e. alternative training intervention) control group(s); (outcome) at least one measure of PF (e.g. jump height) and/or SSP (e.g. time trial) before and after training; and (study design) multi-groups randomized and non-randomized controlled trials. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodological quality of the included studies. The DerSimonian and Laird random-effects model was used to compute the meta-analyses, reporting effect sizes (ES, i.e. Hedges’ g) with 95% confidence intervals (95% CIs). Statistical significance was set at p ≤ 0.05. Certainty or confidence in the body of evidence for each outcome was assessed using Grading of Recommendations Assessment, Development, and Evaluation (GRADE), considering its five dimensions: risk of bias in studies, indirectness, inconsistency, imprecision, and risk of publication bias.

Results

A total of 11,028 studies were identified with 26 considered eligible for inclusion. The median PEDro score across the included studies was 5.5 (moderate-to-high methodological quality). The included studies involved a total of 618 WSA of both sexes (330 participants in the intervention groups [31 groups] and 288 participants in the control groups [26 groups]), aged between 10 and 26 years, and from different sports disciplines such as swimming, triathlon, rowing, artistic swimming, and water polo. The duration of the training programmes in the intervention and control groups ranged from 4 to 36 weeks. The results of the meta-analysis indicated no effects of PJT compared to control conditions (including specific-active controls) for in-water vertical jump or agility (ES =  − 0.15 to 0.03; p = 0.477 to 0.899), or for body mass, fat mass, and thigh girth (ES = 0.06 to 0.15; p = 0.452 to 0.841). In terms of measures of PF, moderate-to-large effects were noted in favour of the PJT groups compared to the control groups (including specific-active control groups) for one-repetition maximum back squat strength, horizontal jump distance, squat jump height, and countermovement jump height (ES = 0.67 to 1.47; p = 0.041 to < 0.001), in addition to a small effect noted in favour of the PJT for SSP time-trial speed (ES = 0.42; p = 0.005). Certainty of evidence across the included studies varied from very low-to-moderate.

Conclusions

PJT is more effective to improve measures of PF and SSP in WSA compared to control conditions involving traditional sport-specific training as well as alternative training interventions (e.g. resistance training). It is worth noting that the present findings are derived from 26 studies of moderate-to-high methodological quality, low-to-moderate impact of heterogeneity, and very low-to-moderate certainty of evidence based on GRADE.

Trial registration The protocol for this systematic review with meta-analysis was published in the Open Science platform (OSF) on January 23, 2022, under the registration doi https://doi.org/10.17605/OSF.IO/NWHS3 (internet archive link: https://archive.org/details/osf-registrations-nwhs3-v1).

Effects of functional training on sprinting, jumping, and functional movement in athletes: A systematic review

This systematic review aims to illuminate the effects of functional training on sprinting, jumping, and functional movements in athletes. A systematic search of electronic databases—that include PubMed, EBSCOhost (Sport Discus), SCOPUS, ProQuest, Google Scholar, and additional references—was carried out using keywords associated with functional training, jumping, sprinting, functional movement skills, and athletes, in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement criteria. The Physiotherapy Evidence Database (PEDro) scale was used to measure the methodological quality of the studies included in the systematic review. Results: From a total of 220 studies, 15 included ones met all eligibility criteria and were scored between 4-5 points—considered as“ moderate quality”—by the PEDro scale. Most studies recorded positive effects of functional training on athletes’ sprinting, jumping, and functional movement. In contrast, a small number of studies did not find any positive effects of functional training on sprinting, squat jump, vertical jump, and countermovement jump due to the short duration and frequency of the training, as well as the lack of additional exercises that come with the interventions. Furthermore, the reviewed studies reveal that there is limited research within the literature on 5, 15, 25, and 50 m sprinting, squat jump, quadrant jump, and functional movement in athletes. Conclusion: Although the length of training interventions varied across studies in this systematic review, functional training interventions were found to help improve athletes’ performance. The review reveals that training duration, intensity, and frequency are some critical variables that need to be taken into account when developing a successful functional training intervention for athletes. More studies are required to evaluate the influence of different accessible functional training durations on athletes’ sprinting, jumping performance, and functional movement. Finally, further research needs to be done to investigate the impacts of functional training on performance and movement skills of male and female athletes at all levels in other sports.

Systematic Review Registration: https://inplasy.com/inplasy-2022-5-0130/, identifier INPLASY202250130

Effects of plyometric training on skill and physical performance in healthy tennis players: A systematic review and meta-analysis

Background: Plyometric training (PT) has been researched extensively in athletic populations. However, the effects of PT on tennis players are less clear. Methods: We aim to consolidate the existing research on the effects of PT on healthy tennis players' skill and physical performance. On 30th May 2022, a comprehensive search of SCOPUS, PubMed, Web of Science, and SPORTDiscus (via EBSCOhost) databases was performed. PICOS was employed to define the inclusion criteria: 1) healthy tennis players; 2) a PT program; 3) compared a plyometric intervention to a control group or another exercise group, and single-group trials; 4) tested at least one measures of tennis skill or physical performance; and 5) non-randomized study trials and randomized control designs. Individual studies' methodological quality was evaluated by using the Cochrane RoB-2 and ROBINS-I instruments. Using Grading of Recommendations Assessment, Development, and Evaluation (GRADE), the certainty of the body of evidence for each outcome was assessed, and Comprehensive Meta-Analysis software was employed for the meta-analysis. Results: Twelve studies comprising 443 tennis players aged 12.5-25 years were eligible for inclusion. The PT lasted from 3 to 9 weeks. Eight studies provided data to allow for the pooling of results in a meta-analysis. A moderate positive effect was detected for PT programs on maximal serve velocity (ES = 0.75; p < 0.0001). In terms of measures of physical performance, small to moderate (ES = 0.43-0.88; p = 0.046 to < 0.001) effects were noted for sprint speed, lower extremity muscle power, and agility. While no significant and small effect was noted for lower extremity muscle strength (ES = 0.30; p = 0.115). We found no definitive evidence that PT changed other parameters (i.e., serve accuracy, upper extremity power and strength, reaction time, and aerobic endurance). Based on GRADE, the certainty of evidence across the included studies varied from very low to moderate. Conclusion: PT may improve maximal serve velocity and physical performance components (sprint speed, lower extremity muscular power, and agility) for healthy tennis players; however, more high-quality evidence about the effects of PT on the skill and physical performance of tennis players merits further investigation. Systematic Review Registration: [https://inplasy.com/], identifier [INPLASY202250146].

Effects of Physical Exercise on Executive Function in Adults with Depression: A Systematic Review and Meta-Analysis

Executive function is among the most affected cognitive dimensions in depression. Physical exercise may improve executive function (e.g., working memory, inhibition, cognitive flexibility), although this is without consensus on adults with depression. Through this systematic review, we aim to elucidate the effects of physical exercise programs on executive functions in adults with depression. The literature search was performed in four relevant electronic databases, combining keywords and medical subject headings, from inception until September 2022. Controlled interventions, involving adults with depression, and reporting working memory, inhibition, and/or cognitive flexibility pre-post-intervention data, were considered includable. Results from meta-analyses included effect size (ES, i.e., Hedges' g) values reported with 95% confidence intervals (95%CIs), with p set at ≤0.05. Seven studies were included, including 202 men and 457 women (age: 21.0-51.2 years; mild-moderate depression). For working memory, a small favoring effect was observed in the experimental groups compared with controls (ES = 0.33, 95%CI = 0.04-0.61; p = 0.026; I² = 64.9%). For inhibition, physical exercise had a small favoring non-significant effect compared with controls (ES = 0.28, 95%CI = -0.17-0.74; p = 0.222; I² = 72.4%). Compared with the control group, physical exercise had a trivial effect on cognitive flexibility (ES = 0.09, 95%CI = -0.21-0.39; p = 0.554; I² = 68.4%). In conclusion, physical exercise interventions may improve working memory behavioral measures in adults with mild-to-moderate depression when compared with active and passive control conditions. However, the reduced number of available high-quality studies precludes more lucid conclusions.

The effects of plyometric jump training on physical fitness attributes in basketball players: A meta-analysis

BACKGROUND

There is a growing body of experimental evidence examining the effects of plyometric jump training (PJT) on physical fitness attributes in basketball players; however, this evidence has not yet been comprehensively and systematically aggregated. Therefore, our objective was to meta-analyze the effects of PJT on physical fitness attributes in basketball players, in comparison to a control condition.

METHODS

A systematic literature search was conducted in the databases PubMed, Web of Science, and Scopus, up to July 2020. Peer-reviewed controlled trials with baseline and follow-up measurements investigating the effects of PJT on physical fitness attributes (muscle power, i.e., jumping performance, linear sprint speed, change-of-direction speed, balance, and muscle strength) in basketball players, with no restrictions on their playing level, sex, or age. Hedge's g effect sizes (ES) were calculated for physical fitness variables. Using a random-effects model, potential sources of heterogeneity were selected, including subgroup analyses (age, sex, body mass, and height) and single training factor analysis (program duration, training frequency, and total number of training sessions). Computation of meta-regression was also performed.

RESULTS

Thirty-two studies were included, involving 818 total basketball players. Significant (p < 0.05) small-to-large effects of PJT were evident on vertical jump power (ES = 0.45), countermovement jump height with (ES = 1.24) and without arm swing (ES = 0.88), squat jump height (ES = 0.80), drop jump height (ES = 0.53), horizontal jump distance (ES = 0.65), linear sprint time across distances ≤10 m (ES = 1.67) and >10 m (ES = 0.92), change-of-direction performance time across distances ≤40 m (ES = 1.15) and >40 m (ES = 1.02), dynamic (ES = 1.16) and static balance (ES = 1.48), and maximal strength (ES = 0.57). The meta-regression revealed that training duration, training frequency, and total number of sessions completed did not predict the effects of PJT on physical fitness attributes. Subgroup analysis indicated greater improvements in older compared to younger players in horizontal jump distance (>17.15 years, ES = 2.11; ≤17.15 years, ES = 0.10; p < 0.001), linear sprint time >10 m (>16.3 years, ES = 1.83; ≤16.3 years, ES = 0.36; p = 0.010), and change-of-direction performance time ≤40 m (>16.3 years, ES = 1.65; ≤16.3 years, ES = 0.75; p = 0.005). Greater increases in horizontal jump distance were apparent with >2 compared with ≤2 weekly PJT sessions (ES = 2.12 and ES = 0.39, respectively; p < 0.001).

CONCLUSION

Data from 32 studies (28 of which demonstrate moderate-to-high methodological quality) indicate PJT improves muscle power, linear sprint speed, change-of-direction speed, balance, and muscle strength in basketball players independent of sex, age, or PJT program variables. However, the beneficial effects of PJT as measured by horizontal jump distance, linear sprint time >10 m, and change-of-direction performance time ≤40 m, appear to be more evident among older basketball players.

Effects of Sport-Based Exercise Interventions on Executive Function in Older Adults: A Systematic Review and Meta-Analysis

Exercise programs of moderate-to-vigorous intensity have been shown to improve the cognitive performance of older people. However, the specific effects of sports-based exercise programs on cognitive performance, particularly executive functions, remain unclear. Therefore, the purpose of this study is to clarify the effects of sports-based exercise programs on executive functions in older adults using a systematic review and meta-analysis of the scientific literature. A systematic review was conducted between 1 March and 1 July 2022, to look for published scientific evidence that analyzed different sports programs that may have affected executive function in healthy older adults. Longitudinal studies, which assessed the effects of sports interventions on healthy older adults, were identified through a systematic search of the four principal electronic databases: Web of Science, PubMed, Scopus, and EBSCO. A total of nine studies with a total of 398 subjects met the inclusion criteria and were classified based on one or more of the following categories: working memory, inhibition, and cognitive flexibility. The DerSimonian and Laird random-effects model was performed using the Comprehensive Meta-Analysis software to facilitate the analysis of the studies. Statistical significance was set at p ≤ 0.05. In terms of working memory, a small but positive significant effect was noted for the intervention group compared to the control group (effect size (ES) = 0.35, 95% confidence interval (CI) = 0.04-0.67; p = 0.029; I² = 36.7%); in terms of inhibition, the intervention had a small favoring but no significant effect compared to the control group (ES = 0.20, 95% CI = -0.42-0.84; p = 0.517; I² = 78.8%); and in terms of cognitive flexibility, the intervention had a small favoring but no significant effect compared to the control group (ES = 0.39, 95% CI = -0.11-0.89; p = 0.131; I² = 75.5%). Our findings suggest that healthy older adults should be encouraged to participate in sports to improve their working memory; however, more studies are required in this area to reach more robust conclusions. This systematic review was registered with the International Prospective Register of Systematic Reviews (registration number: CRD42022284788).

Effects of Sport-Based Interventions on Executive Function in Older Adults: A Systematic Review and Meta-Analysis Protocol

Background: Moderate-to-vigorous intensity exercise programs have proven to exert positive effects on the cognitive performance of older people. However, the specific effects sport-based exercise programs have on cognitive performance, upon executive functions, remain unclear. Therefore, the purpose of this study is to clarify the effects of sport-based exercise programs on executive functions in older adults, through a systematic review protocol of the scientific literature, with a meta-analysis. Methods: The search was performed in the Web of Science, PubMed, Scopus, and EBSCO electronic databases by combining keywords and different medical subject headings (MeSH) to identify and evaluate the relevant studies from inception up until June 2022. This study considers longitudinal studies with at least one experimental group and pre- and post-intervention measurements involving healthy older adults of 60 years of age or older. Studies have to consider one or more measures of executive function, including dimensions of working memory, inhibition, and cognitive flexibility, in order to meet the eligibility criteria for inclusion in this report. The Physiotherapy Evidence Database (PEDro) scale was used for methodological quality assessment studies. The DerSimonian and Laird random-effects model was used to compute the meta-analyses and report effect sizes (ES, i.e., Hedges’ g) with 95% confidence intervals (95% CIs), and a statistical significance set at p ≤ 0.05. The ES values were calculated for executive function globally and for each dimension of executive function (e.g., working memory, inhibition, cognitive flexibility) in the experimental and control/comparator groups using the mean and standard deviation values before and after the intervention period. Conclusions: Our systematic review aims to clarify the effects of sport-based exercise programs on executive functions in older adults. The results may help practitioners and stakeholders to provide better evidence-based decisions regarding sport-based exercise program implementation for older adults, and to help them to optimize cognitive functions during the aging process. Ethical permission is not required for this study. Systematic review registration: this systematic review is registered with the International Prospective Register of Systematic Reviews (PROSPERO; registration number: CRD42022284788).

Vertical Jump Data from Inertial and Optical Motion Tracking Systems

Motion capture (MOCAP) is a widely used technique to record human, animal, and object movement for various applications such as animation, biomechanical assessment, and control systems. Different systems have been proposed based on diverse technologies, such as visible light cameras, infrared cameras with passive or active markers, inertial systems, or goniometer-based systems. Each system has pros and cons that make it usable in different scenarios. This paper presents a dataset that combines Optical Motion and Inertial Systems, capturing a well-known sports movement as the vertical jump. As a reference system, the optical motion capture consists of six Flex 3 Optitrack cameras with 100 FPS. On the other hand, we developed an inertial system consisting of seven custom-made devices based on the IMU MPU-9250, which includes a three-axis magnetometer, accelerometer and gyroscope, and an embedded Digital Motion Processor (DMP) attached to a microcontroller mounted on a Teensy 3.2 with an ARM Cortex-M4 processor with wireless operation using Bluetooth. The purpose of taking IMU data with a low-cost and customized system is the deployment of applications that can be performed with similar hardware and can be adjusted to different areas. The developed measurement system is flexible, and the acquisition format and enclosure can be customized. The proposed dataset comprises eight jumps recorded from four healthy humans using both systems. Experimental results on the dataset show two usage examples for measuring joint angles and COM position. The proposed dataset is publicly available online and can be used in comparative algorithms, biomechanical studies, skeleton reconstruction, sensor fusion techniques, or machine learning models.

Programming Plyometric-Jump Training in Soccer: A Review

The aim of this review was to describe and summarize the scientific literature on programming parameters related to jump or plyometric training in male and female soccer players of different ages and fitness levels. A literature search was conducted in the electronic databases PubMed, Web of Science and Scopus using keywords related to the main topic of this study (e.g., “ballistic” and “plyometric”). According to the PICOS framework, the population for the review was restricted to soccer players, involved in jump or plyometric training. Among 7556 identified studies, 90 were eligible for inclusion. Only 12 studies were found for females. Most studies (n = 52) were conducted with youth male players. Moreover, only 35 studies determined the effectiveness of a given jump training programming factor. Based on the limited available research, it seems that a dose of 7 weeks (1−2 sessions per week), with ~80 jumps (specific of combined types) per session, using near-maximal or maximal intensity, with adequate recovery between repetitions (<15 s), sets (≥30 s) and sessions (≥24−48 h), using progressive overload and taper strategies, using appropriate surfaces (e.g., grass), and applied in a well-rested state, when combined with other training methods, would increase the outcome of effective and safe plyometric-jump training interventions aimed at improving soccer players physical fitness. In conclusion, jump training is an effective and easy-to-administer training approach for youth, adult, male and female soccer players. However, optimal programming for plyometric-jump training in soccer is yet to be determined in future research.

Effects of Maturation Stage on Sprinting Speed Adaptations to Plyometric Jump Training in Youth Male Team Sports Players: A Systematic Review and Meta-Analysis

Purpose

To determine the effects of maturation stage (eg, classified in the same intervention protocol as early-, and late-mature) on linear sprinting speed adaptations to plyometric jump training (PJT) in youth (aged <18 years) male team sports players.

Patients and Methods

Eligibility criteria was determined based on PICOS: (P) healthy youth male team sport players classified in the same intervention protocol in ≥2 maturation-related categories, based on a recognized maturation stage-determination method, including (but not limited to) Tanner stage; peak height velocity (eg, Mirwald method); radiography-based method (eg, Fels method); (I) athletes exposed to PJT with a minimum of 4 weeks duration; (C) athletes non-exposed to PJT (non-dedicated intervention, ie, only field-based regular training) or performing a parallel intervention not-related with PJT organized by maturation levels; (O) sprinting speed (eg, time, maximal sprint speed) measured in any linear sprint test trajectories before and after the intervention; (S) only randomized controlled and/or parallel trials. Searches were conducted on December 2021 in EMBASE, PubMed, Scopus, SPORTDiscus and Web of Science, restricted to Portuguese, Spanish and English languages, with no restrictions regarding publication date, and no filters applied. The PEDro scale was used to assess the risk of bias in the included studies. Meta-analysis was computed using the inverse variance random-effects model. The significance level was set at p < 0.05.

Results

The search identified 1219 titles. From those, four studies were selected for qualitative and quantitative synthesis. Four studies provided data for sprinting performance, involving 10 experimental and 8 control groups showing a small effect of trained participants on sprinting performance (ES = 0.31; p = 0.064; I2 = 41.3%) when compared to controls. No significant moderator effect was noted for somatic maturity (p = 0.473 between groups).

Conclusion

PJT had no significant effect on sprinting performance, although the inclusion criteria partially may explain that.

Guidelines for performing systematic reviews in sports science

Most of the reviews carried out in sports science have used the general items suggested by Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Due to the specific requirements of each knowledge area, several modifications of the PRISMA are necessary to optimize the process of the systematic reviews and, in consequence, the quality of the conclusions provided in this type of study. Therefore, this work aimed to adapt PRISMA to provide specific guidelines to carry out systematic reviews in sports science. The methodology criteria (search strategy, databases, and eligibility) and the results section (flow diagrams and study contents) were adapted based on previous studies, and several new considerations were added to design the new guidelines. We compiled 28 items suggested by sports science researchers and included two new items: (i) population/problem (i.e., age, level, and country) and (ii) the entire training process, which is monitored and compared between groups (e.g., total training load). To maximize the benefit of this document, we encourage people to read it in conjunction with the PRISMA statement. The main differences between PRISMA and the PRISMA adapted to sports science were related to registration, search strategy, flow diagrams, and results. Application of the new guidelines could improve the information provided to readers and make it easier to generalize and compare the results in sports science.

Combined Plyometric and Short Sprint Training in U-15 Male Soccer Players: Effects on Measures of Jump, Speed, Change of Direction, Repeated Sprint, and Balance

This study examined the effect of 8 weeks of biweekly combined plyometric and short sprint training into the typical within-season training schedule of youth male soccer players. Participants were allocated at random to an experimental group (EG; n = 17, age: 14.6 ± 0.5 years, body mass: 60.5 ± 7.1 kg, height: 1.64 ± 0.08 m, body fat: 11.3 ± 1.4%) and a control group (CG; n = 17, age: 14.6 ± 0.4 years, body mass: 61.0 ± 3.9 kg, height: 1.67 ± 0.05 m, body fat: 11.8 ± 1.4%). Measures obtained pre- and post-intervention included vertical and horizontal jump performances (i.e., squat jump (SJ), countermovement jump with aimed arms (CMJA), and five-jump test (FJT)) and sprint performances (i.e., 10 and 30 m sprint). In addition, change-of-direction ability (sprint with 90° Turns (S90°) and sprint 9–3–6–3–9 m with backward and forward running (SBF)), repeated shuttle sprint ability (RSSA), and dynamic balance performance (Y balance test) were measured pre- and post-intervention. The EG experienced higher jump (all p < 0.05; d ≥ 0.71), sprint (all p < 0.05; d ≥ 0.64), change-of-direction ability (all p < 0.05; d ≥ 0.66), RSSA (all parameters except the fatigue index p < 0.01; d ≥ 0.71), and dynamic balance (all p ≤ 0.05; d ≥ 0.50) improvement compared to the CG. Adding biweekly combined plyometric and short sprint training to standard training improves the athletic performance of youth male soccer players (under 15 (U15)).

Effects of Plyometric Jump Training on Balance Performance in Healthy Participants: A Systematic Review With Meta-Analysis

Background: Postural balance represents a fundamental movement skill for the successful performance of everyday and sport-related activities. There is ample evidence on the effectiveness of balance training on balance performance in athletic and non-athletic population. However, less is known on potential transfer effects of other training types, such as plyometric jump training (PJT) on measures of balance. Given that PJT is a highly dynamic exercise mode with various forms of jump-landing tasks, high levels of postural control are needed to successfully perform PJT exercises. Accordingly, PJT has the potential to not only improve measures of muscle strength and power but also balance. Objective: To systematically review and synthetize evidence from randomized and non-randomized controlled trials regarding the effects of PJT on measures of balance in apparently healthy participants. Methods: Systematic literature searches were performed in the electronic databases PubMed, Web of Science, and SCOPUS. A PICOS approach was applied to define inclusion criteria, (i) apparently healthy participants, with no restrictions on their fitness level, sex, or age, (ii) a PJT program, (iii) active controls (any sport-related activity) or specific active controls (a specific exercise type such as balance training), (iv) assessment of dynamic, static balance pre- and post-PJT, (v) randomized controlled trials and controlled trials. The methodological quality of studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. This meta-analysis was computed using the inverse variance random-effects model. The significance level was set at p <0.05. Results: The initial search retrieved 8,251 plus 23 records identified through other sources. Forty-two articles met our inclusion criteria for qualitative and 38 for quantitative analysis (1,806 participants [990 males, 816 females], age range 9-63 years). PJT interventions lasted between 4 and 36 weeks. The median PEDro score was 6 and no study had low methodological quality (≤3). The analysis revealed significant small effects of PJT on overall (dynamic and static) balance (ES = 0.46; 95% CI = 0.32-0.61; p < 0.001), dynamic (e.g., Y-balance test) balance (ES = 0.50; 95% CI = 0.30-0.71; p < 0.001), and static (e.g., flamingo balance test) balance (ES = 0.49; 95% CI = 0.31-0.67; p < 0.001). The moderator analyses revealed that sex and/or age did not moderate balance performance outcomes. When PJT was compared to specific active controls (i.e., participants undergoing balance training, whole body vibration training, resistance training), both PJT and alternative training methods showed similar effects on overall (dynamic and static) balance (p = 0.534). Specifically, when PJT was compared to balance training, both training types showed similar effects on overall (dynamic and static) balance (p = 0.514). Conclusion: Compared to active controls, PJT showed small effects on overall balance, dynamic and static balance. Additionally, PJT produced similar balance improvements compared to other training types (i.e., balance training). Although PJT is widely used in athletic and recreational sport settings to improve athletes' physical fitness (e.g., jumping; sprinting), our systematic review with meta-analysis is novel in as much as it indicates that PJT also improves balance performance. The observed PJT-related balance enhancements were irrespective of sex and participants' age. Therefore, PJT appears to be an adequate training regime to improve balance in both, athletic and recreational settings.

Effects of Combined Plyometric and Short Sprints Training on Athletic Performance of Male U19 Soccer Players

This project investigated adding 8 weeks of biweekly plyometric and short sprints training into standard training in elite youth soccer players. An experimental group (EG, n = 18, age: 17.6 ± 0.6 years, body mass: 67.6 ± 5.8 kg, height: 1.75 ± 0.06 m, and body fat: 11.5 ± 1.6%) and control group (CG, n = 18, age: 17.5 ± 0.6 years, body mass: 68.8 ± 3.6 kg, height: 1.77 ± 0.04 m, and body fat: 11.7 ± 1.2%) participated. Pre-intervention and post-intervention measures were squat-jump (SJ), countermovement-jump (CMJ), standing long jump (SLJ), 5 and 20 m sprints, change-of-direction ability (4 × 5 m sprint test [S 4 × 5 m] and sprint 9-3-6-3-9 m with backward and forward running [SBF]), repeated change of direction (RCOD), and static balance (the stork balance test). For all parameters, significant (p < 0.001, ηp2 > 0.10) time and interaction (group × time) effects were observed. For three parameters (SBF, RCOD fastest time, and SLJ) no significant group effects were observed. The EG consistently showed a significantly higher performance level than the CG and a higher amount of effect sizes d (EG: d_range: 1.27–2.61; CG: d_range: 0.13–0.79) as an indicator for the development of performance between pre-intervention and post-intervention measures. Adding biweekly plyometric and short sprint training to standard training improves the athletic performance of young soccer players. Such plyometric and short sprint training conditioning can be highly recommended as part of the annual short training program for male elite under-19 (U19) soccer players.

Effects of Three Preseason Training Programs on Speed, Change-of-Direction, and Endurance in Recreationally Trained Soccer Players

Background: Modern coaches experience a drastic reduction of the available training time with an increasingly large number of competitions during the competitive season. Thus, they must choose wisely the most efficient methods to improve the physical fitness of their players during the preseason. Among all the methods, this study compared the effects of plyometric training (PT), sprint interval training (SIT), and small-sided games (SSGs) on the performance of recreationally trained soccer players.

Methods: Seventy-three participants were randomly assigned in one of the three experimental groups (i.e., PT [n = 23], SIT [n = 26] or SSGs [n = 24]) and completed two sessions per week for a total of 3 weeks. Meanwhile, the whole group maintained their habitual soccer-specific training program who do not interfere in the preparation of the season. Repeated sprint ability (RSA), maximal aerobic speed (MAS), and a 30-m sprint were assessed at baseline (PRE) and post-training (POST).

Results: Performance in SSGs decreased for the average speed from 0 to 10 m (V_0−10m; −0.84 km h⁻¹, −4 ± 5%, p < 0.001), the maximal distance (D_max) covered in the 30-s RSA test (−3.65 m, −3 ± 6%, p < 0.01) and MAS (−0.52 km h⁻¹, −3 ± 6%, p < 0.01). PT increased the mean distance (D_mean) covered in the 30-s RSA test (+5.98 m, 5 ± 4%, p < 0.001) and MAS (+0.58 km h⁻¹, 7 ± 5%, p < 0.01) while an improvement of all parameters but the maximal sprint speed reached during the 30-m trip (V_max) was found in the SIT group (V_0−10m: +1.462 km h⁻¹, 8 ± 5%, p < 0.001; D_max: +7.89 m, 6 ± 5%, p < 0.001; D_mean: +8.69 m, 7 ± 5%, p < 0.001 and MAS: +1.74 km h⁻¹, 12 ± 8%, p < 0.001). All SSG POST values were significantly lower than PT and SIT (p < 0.01). D_mean and MAS in POST were also significantly higher in SIT than in the PT group (p < 0.001).

Conclusion: This study suggests that both PT and SIT could be a better alternative to SSGs to boost performances during preseason. Moreover, SIT seems to produce higher improvements in physical performances than PT.

Effects of Plyometric and Short Sprint with Change-of-Direction Training in Male U17 Soccer Players

This project investigated the effect of adding 8 weeks of bi-weekly plyometric and short sprint with change-of-direction (PSSCoD) training into standard training for elite youth soccer players from Tunisia. A training group (n = 18; age: 16.6 ± 0.5 years; body mass: 63.2 ± 4.8 kg; stature: 1.73 ± 0.07 m; body fat: 11.2 ± 1.7%), and control group (n = 16; age: 16.6 ± 0.5 years; body mass: 63.6 ± 4.3 kg; height: 1.73 ± 0.06 m; body fat: 11.6 ± 1.5%) participated. The pre- and post-intervention measures were squat-jump (SJ), countermovement jump (CMJ), standing long jump (SLJ), 5 m and 20 m sprint, change-of-direction ability (4 × 5 m sprint test (S 4 × 5 m)), repeated sprint ability (RSA), and static balance (stork balance test). The training group displayed superior jump (all p < 0.05; d > 0.49), sprint (p < 0.05; d > 0.52), change-of-direction ability (p < 0.01; d = 0.78), RSA (p < 0.01; d > 0.70), and static balance (p < 0.05; d > 0.49) improvements. Adding bi-weekly PSSCoD improves the athletic performance of young soccer players.

Effects of Plyometric Jump Training on Repeated Sprint Ability in Athletes: A Systematic Review and Meta-Analysis

BACKGROUND

There is a growing body of research examining the effects of plyometric jump training (PJT) on repeated sprint ability (RSA) in athletes. However, available studies produced conflicting findings and the literature has not yet been systematically reviewed. Therefore, the effects of PJT on RSA indices remain unclear.

OBJECTIVE

To explore the effects of PJT on RSA in athletes.

METHODS

Searches for this review were conducted in four databases. We included studies that satisfied the following criteria: (1) examined the effects of a PJT exercise intervention on measures of RSA; (2) included athletes as study participants, with no restriction for sport practiced, age or sex; and (3) included a control group. The random-effects model was used for the meta-analyses. The methodological quality of the included studies was assessed using the PEDro checklist.

RESULTS

From 6367 search records initially identified, 13 studies with a total of 16 training groups (n = 198) and 13 control groups (n = 158) were eligible for meta-analysis. There was a significant effect of PJT on RSA best sprint (ES = 0.75; p = 0.002) and RSA mean sprint (ES = 0.36; p = 0.045) performance. We did not find a significant difference between control and PJT for RSA fatigue resistance (ES = 0.16; p = 0.401). The included studies were classified as being of "moderate" or "high" methodological quality. Among the 13 included studies, none reported injury or any other adverse events.

CONCLUSION

PJT improves RSA best and mean performance in athletes, while there were no significant differences between control and PJT for RSA fatigue resistance. Improvements in RSA in response to PJT are likely due to neuro-mechanical factors (e.g., strength, muscle activation and coordination) that affect actual sprint performance rather than the ability to recover between sprinting efforts.

Effects of Plyometric Jump Training on Jump and Sprint Performance in Young Male Soccer Players: A Systematic Review and Meta-analysis

BACKGROUND

Even from a young age, modern soccer requires high levels of physical fitness development, particularly jumping and sprinting. Plyometric jump training (PJT), combined with young athletes' regular soccer sessions, has the potential to improve jumping and sprinting. However, studies exploring the effects of PJT are generally limited by small sample sizes. This problem of underpowered studies may, thus, be resolved by pooling study results in a meta-analysis.

OBJECTIVE

The objective of this systematic review with meta-analysis (SRMA) was to assess the effects of plyometric jump training (PJT) on jumping and sprinting among young male soccer players.

METHODS

The SRMA included peer-reviewed articles that incorporated PJT in healthy players (i.e., < 23 years of age), a control group, and a measure of jumping or sprinting. Means and standard deviations of outcomes were converted to Hedges' g effect sizes (ES), using the inverse variance random-effects model. Moderator analyses were conducted for PJT duration, frequency, total number of sessions, participants' chronological age, and FIFA age categories (i.e., U-17 vs. U-20 vs. U-23). A multivariate random-effects meta-regression was also conducted.

RESULTS

Thirty-three studies were included, comprising 1499 participants. PJT improved vertical jump tests (ES = 0.60-0.98; all p < 0.01) and linear sprint performance (ES = 0.60-0.98; p < 0.03). Interventions of > 7 weeks and > 14 PJT sessions induced greater effects compared to PJT with ≤ 7 weeks and ≤ 14 total sessions on 10-m sprint performance (between group p = 0.038).

CONCLUSION

PJT is effective in improving jumping and sprinting performance among young male soccer players. Greater 10-m linear sprinting improvements were noted after interventions > 7-week duration and > 14 sessions, suggesting a greater return from exposure to longer PJT interventions, partially in support for the adoption of a long-term approach to athletic development in young athletes. However, with reference to the findings of the meta-regression, and those from the remaining subgroup and single factors analysis, a robust confirmation regarding the moderator role of participant's age or PJT configuration effects on young soccer player's fitness qualities needed.

Plyometric jump training effects on the physical fitness of individual-sport athletes: a systematic review with meta-analysis

Background

The aim of this study is to conduct a systematic review with meta-analysis to explore the effects of plyometric jump training (PJT) on the physical fitness of individual sport athletes (ISA).

Methods

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched through PubMed, Web of Science, and SCOPUS electronic databases. We included controlled studies that incorporated a PJT intervention among ISA (with no restriction for age or sex), that included a pre-to-post intervention assessment of physical fitness (e.g., sprint; jump). From the included studies, relevant data (e.g., PJT and participants characteristics) was extracted. We assessed the methodological quality of the included studies using the PEDro scale. Using a random-effects model, meta-analyses for a given outcome was conducted. Means and standard deviations for a measure of pre-post-intervention physical fitness from the PJT and control groups were converted to Hedges' g effect size (ES). Heterogeneity was assessed using the I ² statistic. The risk of bias was explored using the extended Egger's test. The statistical significance threshold was set at p < 0.05. Moderator analyses were conducted according to the sex, age and sport background of the athletes.

Results

Twenty-six studies of moderate-high methodological quality were included (total participants, n = 667). Compared to controls, PJT improved vertical jump (ES = 0.49; p < 0.001; I = 0.0%), linear sprint (ES = 0.23; p = 0.032; I ² = 10.9%), maximal strength (ES = 0.50; p < 0.001; I² = 0.0%) and endurance performance (ES = 0.30; p = 0.028; I² = 11.1%). No significant effect was noted for sprint with change of direction (ES = 0.34; p = 0.205; I² = 70.9%). Athlete's sex, age and sport background had no modulator role on the effect of PJT on vertical jump, linear sprint, maximal strength and endurance performance. Among the included studies, none reported adverse effects related to the PJT intervention.

Conclusions

PJT induces small improvements on ISA physical fitness, including jumping, sprinting speed, strength and endurance.

Effects of Small-Sided Games vs. Running-Based High-Intensity Interval Training on Physical Performance in Soccer Players: A Meta-Analytical Comparison

Objectives: This systematic review with meta-analysis (SRMA) was conducted to compare the effects of SSG-based interventions vs. running-based HIIT interventions on soccer players' sprinting time (ST), vertical height jump (VJH), and change of direction time (CODt). Data Sources: The data sources utilized were Web of Science, Scopus, SPORTDiscus, and PubMed. Results: An electronic search yielded 650 articles, six of which were included in the present study. Between-group analysis found a significant favoring effect of HIIT-based over SSG-based training interventions for the improvement of linear sprinting time (ES = 0.42; p = 0.012). A within-group analysis revealed a significant favoring effect of HIIT-based training interventions for improving linear sprinting time (ES = 0.42; p = 0.008) and CODt (ES = 1.04; p = 0.005) despite a non-significant effect on VJH (ES = 0.47; p = 0.22). Conclusions: The meta-analytical comparison revealed favoring the effect of running-based HIIT over SSG-based interventions in sprinting performance, although no significant differences were observed for jumping and CODt performance. The findings suggest that SSG-based programs should be supplemented by other training methods that benefit determinant capacities in soccer players.

Effects of Plyometric Jump Training on Physical Fitness in Amateur and Professional Volleyball: A Meta-Analysis

We aimed to examine the effects of plyometric jump training (PJT) on measures of physical fitness in amateur and professional volleyball players. A systematic electronic literature search was carried out in the databases PubMed, MEDLINE, Web of Science, and SCOPUS. Controlled studies including pre-to-post intervention tests of physical fitness and involving healthy volleyball players regardless of age and sex were considered. A random-effects model was used to calculate effect sizes (ES) between intervention and control groups. Moderator analyses considered programme duration, training frequency, total number of training sessions and jumps, participants' sex, age, and expertise level. The Physiotherapy Evidence Database scale was used to assess the methodological quality of the included studies. Eighteen moderate-to-high quality (median of 5 PEDro points) studies were eligible, comprising a total of 746 athletes. None of the included studies reported injuries related to the PJT intervention. The main findings showed small-to-moderate effects (p < 0.05) of PJT on linear sprint speed (ES = 0.70), squat jump (ES = 0.56), countermovement jump (CMJ) (ES = 0.80), CMJ with arm swing (ES = 0.63), drop jump (ES = 0.81), and spike jump height (ES = 0.84). Sub-analyses of moderator factors included 48 data sets. Only age had a significant effect on CMJ performance. Participants aged ≥16 years achieved greater improvements in CMJ performance compared to <16 years old (ES = 1.28 and 0.38, respectively; p = 0.022). No significant differences (p = 0.422) were identified between amateur (ES = 0.62) and professional volleyball players (ES = 1.01). In conclusion, PJT seems safe and is effective in improving measures of physical fitness in amateur and professional volleyball players, considering studies performed in both male and female.

Effects of Short-Term Plyometric Training on Agility, Jump and Repeated Sprint Performance in Female Soccer Players

The aim of the study was to determine the effects of short-term (4 weeks, twice a week: 8 sessions) plyometric training on agility, jump, and repeated sprint performance in female soccer players. The study comprised 17 females performing this sports discipline. The players were randomly divided into two groups: with plyometric training (PLY) and the control (CON). All players followed the same training program, but the PLY group also performed plyometric exercises. Tests used to evaluate physical performance were carried out immediately before and after PLY. After implementing the short PLY training, significant improvement in jump performance (squat jump: p = 0.04, ES = 0.48, countermovement jump: p = 0.009, ES = 0.42) and agility (p = 0.003, ES = 0.7) was noted in the PLY group. In the CON group, no significant (p > 0.05) changes in physical performance were observed. In contrast, PLY did not improve repeated sprint performance (p > 0.05) among female soccer players. In our research, it was shown that PLY can also be effective when performed for only 4 weeks instead of the 6–12 weeks typically applied.

Effects of Complex Training on Sprint, Jump, and Change of Direction Ability of Soccer Players: A Systematic Review and Meta-Analysis

The aim of this meta-analysis was to evaluate the effects of complex training (CT) on sprint, jump, and change of direction (COD) ability among soccer players. After an electronic search, 10 peer-reviewed articles were considered in the meta-analysis. The athletes included in this meta-analysis were amateur to professional level male soccer players (age range, 14–23 years). These studies incorporated CT in soccer players who were compared to a control group. Significant moderate to large improvements were observed in the CT group [sprint: standard mean difference (SMD) = 0.92–1.91; jump: SMD = 0.96–1.58; COD: SMD = 0.97–1.49] when compared to control groups. Subgroup analysis were also conducted based on age, duration, and competitive level. The beneficial effects of CT were greater in players <18 vs. ≥18 years (linear sprinting; SMD = 2.01 vs. −0.13), after ≥8 vs. <8 weeks (jumping and COD; SMD = 1.55–2.01 vs. 0.31–0.64, respectively) and among professional vs. amateur players (linear sprinting and with COD; SMD = 1.53–1.58 vs. 0.08–0.63, respectively). In conclusion, regular soccer training programs may be supplemented with CT to improve sprint, jump, and COD performance. A longer duration of CT (≥8 weeks) seems to be optimal in improving the physical abilities of soccer players. Professional players and <18 years players may benefit more from CT program.

Effects of Strength vs. Plyometric Training Programs on Vertical Jumping, Linear Sprint and Change of Direction Speed Performance in Female Soccer Players: A Systematic Review and Meta-Analysis

The main purpose of this systematic review and meta-analysis was to compare the effects of strength training (ST) and plyometric training (PT) on vertical jump, linear sprint and change of direction (COD) performance in female soccer players. A systematic search of the PubMed, Web of Science, Google Scholar and SportDiscus databases revealed 12 studies satisfying the inclusion criteria. The inverse-variance random-effects model for meta-analyses was used. Effect sizes (ES) were represented by the standardized mean difference and presented alongside 95% confidence intervals (CI). The magnitude of the main effect was small to moderate (vertical jump (ES 0.53 (95% CI—0.11, 0.95), Z = 2.47 (p = 0.01); linear sprint (ES −0.66 (95% CI—2.03, −0.21), Z = 2.20 (p = 0.03); COD (ES −0.36 (95% CI—0.68, −0.03), Z = 2.17 (p = 0.03)). Subgroup analyses were performed (i.e., ST and PT duration, frequency, session duration and total number of sessions), revealing no significant subgroup differences (p = 0.12–0.88). In conclusion, PT provides better benefits than ST to improve vertical jump, linear sprint and COD performance in female soccer players. However, significant limitations in the current literature prevent assured PT and ST prescription recommendations being made.

Effects of Plyometric Jump Training in Female Soccer Player's Physical Fitness: A Systematic Review with Meta-Analysis

We aimed to assess the effects of plyometric jump training (PJT) on female soccer player’s physical fitness. To this aim, a systematic review with meta-analysis (SRMA) was conducted. The electronic databases PubMed, MEDLINE, Web of Science, and SCOPUS were used. To qualify for inclusion, peer-reviewed studies must have included (i) a PJT programme of ≥2 weeks, (ii) healthy athletes, (iii) a control group, and (iv) physical fitness outcomes (e.g., jump; sprint). Studies were excluded if (i) they incorporated injuried female soccer players, (ii) did not involve PJT or an active control group, (iv) lack of baseline and/or follow-up data. Data was meta-analyzed using the inverse variance random-effects model. Ten moderate-to-high quality studies were included in the analyses, comprising 13 training groups (n = 140) and 10 control groups (n = 110). Small to large (ES = 0.60–2.24; p = 0.040 to <0.001) effects were noted for countermovement jump, drop jump, kicking performance, linear sprint, change of direction speed, and endurance. The moderator analyses (i.e., PJT duration, age groups, competitive level, and soccer experience) revealed no significant differences between groups. In conclusion, PJT may improve the physical fitness of female soccer players. Such improvements might be expected after PJT interventions with six or more weeks of duration, and in players with different chronological ages, competitive levels and soccer experience.