The Association Between Force-Velocity Relationship in Countermovement Jump and Sprint With Approach Jump, Linear Acceleration and Change of Direction Ability in Volleyball Players

Concentric Rate of Force Development, Squat Strength, and Faster Unloading Associated With Change-of-Direction Performance and Its Deficit in Female Volleyball Players

PURPOSE

Athletes who perform faster changes of direction (CODs) often exhibit superior leg strength, jumping performance, and linear sprint performance. However, these abilities only partially correlate with COD deficit (CODD), and relying solely on correlation analysis may lead to misinterpretations due to unaddressed, additive, or confounding effects. This study investigated the association between COD/CODD performance and various jump heights, countermovement-jump (CMJ) phase-specific performance, leg strength, and linear sprint performance. Multiple linear-regression models with stepwise selection were used to explore and adjust the additive effects and confounders of these factors.

METHODS

Eighteen female intercollegiate volleyball athletes performed 10- and 20-m linear sprints and proagility tests, and their CODD and physical performance metrics were measured. Furthermore, squat jump and CMJ height, back-squat 1-repetition maximum (BS1RM) corrected for body mass (relative), and CMJ phase-specific performance, including vertical force and rate of force development during eccentric unloading, yielding, braking, and concentric phases, were measured.

RESULTS

Concentric-phase rate of force development at 100 milliseconds, relative BS1RM, and squat-jump height were retained in the 10-m COD model (adjusted R2 = .515, P = .004). The absolute BS1RM and minimum power at the unloading phase of CMJ were retained in the 10-m CODD model (adjusted R2 = .746, P < .001). In contrast, no variables were retained in the 20-m COD model.

CONCLUSIONS

The results suggest that enhancement of overall leg-contraction power and strength and rapid concentric force production immediately after eccentric braking may enhance 10-m COD/CODD performance in volleyball players.

Maturation-Dependent Variations in Force-Velocity Profiles and Relationship with Spike Jump Performance in Female Volleyball Players

OBJECTIVES

This research explores the vertical force-velocity (FV) profiles of female volleyball players at different maturation stages and examines the correlation between these profiles and spike jump.

METHODS

Forty-two volleyball players (≥1 year training) were grouped by maturation stage-pre-PHV (n=9), mid-PHV (n=14), or post-PHV (n=19)-determined using anthropometric measurements (standing height, sitting height, leg length, and weight) and the Mirwald method to estimate maturity offset. FV profiles were assessed using Samozino's method with countermovement jumps under different loads. ANOVA with Bonferroni post-hoc tests analyzed group differences, while correlation analysis explored links between FV profiles and spike jump height (SJ).

RESULTS

Significant variances were observed among maturity groups concerning FV profile parameters, which included maximal force (F0), maximal velocity (V0), and maximal power (Pmax) (p<0.05, η2=0.19-0.69). Players at more advanced maturity stages demonstrated higher force parameters yet lower velocity values. Furthermore, only weak correlations emerged between spike jump height and parameters such as F0 and Pmax (p<0.05, r=0.31-0.39).

CONCLUSION

Post-PHV female volleyball players exhibited greater force production, but lower velocity compared to pre- and mid-PHV players. The weak correlations between force-velocity profiles and spike jump height suggest that other factors may contribute to spike jump performance. Further research is needed to elucidate these determinants across different maturation stages.

Time-of-Day Effects on Post-Activation Potentiation Protocols: Effects of Different Tension Loads on Agility and Vertical Jump Performance in Judokas

Background and Objectives: This study aimed to investigate the effects of different tension loads in post-activation potentiation protocols on agility and vertical jump performance across different times of day in trained judokas, addressing a significant gap in understanding the interaction between diurnal variations and post-activation potentiation protocol responses in combat sports. Materials and Methods: Seventeen male judokas (age: 21.41 ± 1.37 years) with ≥2 years of training experience participated in the study. Participants completed three different protocols: specific warm-up, the 80% post-activation potentiation protocol, and the 100% post-activation potentiation protocol, performed both in the morning (09:00-11:00) and evening (17:00-19:00) sessions. Performance was assessed using the Illinois Agility Test and countermovement jump. Protocols were randomized and counterbalanced over a 3-week period, with a minimum 48 h recovery between sessions. Statistical analysis employed repeated measures ANOVA (3 × 2) with Greenhouse-Geisser corrections. Results: Significant differences were observed in both protocols and time interactions for agility (F = 41.691, ηp2 = 0.864, p < 0.001; F = 23.893, ηp2 = 0.123, p < 0.001) and countermovement jump performance (F = 7.471, ηp2 = 0.410, p = 0.002; F = 38.651, ηp2 = 0.530, p < 0.001). The 80% post-activation potentiation protocol demonstrated superior performance outcomes compared to both specific warm-up and 100% post-activation potentiation protocols. Evening performances were generally better than morning performances for both agility and countermovement jump; however, the protocols/time interaction was not statistically significant (p > 0.05). Conclusions: The 80% post-activation potentiation protocol was most effective for enhancing both agility and vertical jump performance in judokas, with superior results observed during evening sessions. These findings provide valuable insights for optimizing warm-up strategies in judo competition, suggesting that lower-intensity post-activation potentiation protocols might be more beneficial than maximal loading, particularly during evening competitions.

The effects of different fatigue types on action anticipation and physical performance in high-level volleyball players

This study examined the effects of different fatigue types on action anticipation and physical performance in high-level volleyball players. Twenty-four participants underwent four counterbalanced conditions: 60-min cycling at 60% peak power output, 60-min Stroop task, 60-min cycling at 60% peak power output with Stroop task and 60-min neutral documentary to induce physical fatigue (PF), mental fatigue (MF), dual fatigue (DF) and control group (CG), respectively. Action anticipation (anticipation test and visual search test) and physical performance (countermovement jump, T-test, and spike test) were conducted at baseline, immediately after (Post1), and after 10-min rest (Post2). DF and PF led to significantly lower jump height, T-test completion time, and spiking speed at Post1 and Post2 compared with CG and MF. Compared with PF, DF led to a significant decline in jumping, agility, and spiking performance at Post1 and decreased jumping performance at Post2. MF significantly decreased the reaction time of anticipation test at Post1 compared with CG. Reaction times of visual search test were significantly lower in DF and MF at Post2 compared with CG. It is suggested that PF decreased physical performance, and this is exacerbated in DF. Anticipation performance was affected by MF but not by DF and PF.

Associations Between Sprint Mechanical Properties and Change of Direction Ability and Asymmetries in COD Speed Performance in Basketball and Volleyball Players

This study aimed to assess the associations between sprint force-velocity profile variables with change of direction (COD) performance and to investigate the impact of these variables on asymmetries in COD speed performance. Ninety-nine participants (volleyball players: n = 44, basketball players: n = 55) performed 40 m sprints for Fv relationship calculation, two COD tests (Modified Agility T-test and 505 test). A partial least squares (PLS) regression analysis was conducted to determine the relationships between the variables. The V0 was the most influential variable; it was negatively associated with COD performance variables (β = -0.260, -0.263 and -0.244 for MAT, 505-D and 505-ND, respectively), and F0 (β = 0.169, 0.163) was associated with the COD performance variables (COD deficit D and COD deficit ND, respectively), slightly larger than the effects of Fvslope (β = -0.162, -0.146), DRF (β = -0.159, -0.142) and Pmax (β = -0.162, -0.146). For COD deficit imbalance, the DRF (β = -0.070) was the most influential variable followed by Fvslope (β = -0.068), F0 (β = 0.046) and gender (β = 0.031). V0 and RFmax were the critical variables for improving COD performance that includes linear sprints, while DRF, Fvslope, F0 and Pmax collectively influence 180° COD performance. Meanwhile, DRF and Fvslope were important factors for asymmetries in COD speed performance. It is recommended to use the Fv profile to diagnose different COD movement patterns and then develop training plans accordingly for team sports played on smaller courts, such as basketball and volleyball.

Assessing the Maximal Mechanical Capacities Through the Load-Velocity Relationship in Elite Versus Junior Male Volleyball Players

BACKGROUND

Physical testing is crucial for athlete monitoring, talent identification, optimizing training, and tailoring programs to enhance game-performance in elite competitions.

HYPOTHESIS

Load-velocity (L-V) relationship variables discriminate between elite and junior volleyball players, correlate with volleyball-specific performance, and are generalizable across lower- and upper-body exercises.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 9 elite and 11 junior volleyball players were assessed for the L-V relationship (load-axis intercept [L0], velocity-axis intercept [v0], and area under the L-V relationship line [Aline]) during the countermovement jump (CMJ) and bench press throw (BPT) exercises. Block and spike jump height, as well as standing and jumping spike speed were assessed 24 hours later.

RESULTS

Elite players presented greater magnitude in the L-V variables (P ≤ 0.03; effect size [ES] ≥ 1.06) and higher volleyball-specific performance (P ≤ 0.03; ES ≥ 1.09) than juniors (except for CMJ v0 and Aline). The L-V relationship variables were significantly associated with the block and spike jump height and jumping spike speed only in elite players (r ≥ 0.703 and P ≤ 0.04 in 11 out of 18 correlations). No significant associations were observed between CMJ and BPT for any L-V relationship variable (r ≤ 581; P ≥ 0.08, except for Aline in junior players).

CONCLUSION

The L-V relationship is a practical procedure to assess volleyball players' maximal mechanical capacities, which are associated with volleyball-specific performance in elite players. However, these data should not be used interchangeably between playing standards or exercises.

CLINICAL RELEVANCE

This information might help strength and conditioning coaches to prescribe more effective training programs that focus on developing the specific physical capacities necessary for players to potentially advance to elite status.

Force-velocity-power profiling in flywheel squats: Differences between sports and association with countermovement jump and change of direction performance

The objectives of our study were 1) to examine whether the force-velocity-power (FvP) outcomes in the concentric and eccentric phases of flywheel (FW) squats differ among sports disciplines and 2) to investigate the association between FvP outcome variables and two key sport-performance indicators: countermovement jump height (CMJ) and change of direction (CoD) time involving 90° or 180° turns. Tests were performed by 469 athletes from five different sport disciplines and physical education students. Our results showed that FvP outcomes, when measured during the eccentric phase of the FW squat, effectively differed between athletes from different sports. However, during the concentric phase of the squat, only for the slope variable differences between sports were found. Contrary to our hypothesis, there were no statistically significant correlations between FW squat FvP outcomes and CMJ or CoD test results. These results suggest that FvP outcomes derived from FW squats may lack external validity and cannot be reliably used as a predictor of athletes' jumping and agility performance. The paper discusses possible reasons for the larger differences between sports in eccentric FvP outcomes, as well as the absence of correlations between FvP outcomes and functional tests.

The profiles of single leg countermovement jump kinetics and sprinting in female soccer athletes

The purposes were to evaluate kinetics in lower limbs using single leg countermovement jump (SLCMJ) and to identify the differences in SLCMJ kinetics between sprinting fast players and sprinting slow players in elite university female soccer players. Seventeen participants at the national tournament level completed the survey. SLCMJ and 30 m sprinting tests were performed. A force-plate was used to collect the data of the SLCMJ test. Significant differences of concentric maximum rate of force development (RFD), concentric RFD, concentric RFD/body weight (BW), peak net takeoff force/BW, peak power, and peak power/BW existed between both legs during the SLCMJ among all the participants. For further analysis, the participants were divided into fast group and slow group based on sprinting performance. Significant differences existed between the two groups in concentric peak velocity (nondominant, p = 0.028) and vertical velocity at takeoff (nondominant, p = 0.021). Concentric maximum RFD (p = 0.036) was significantly different between both legs in the slow group. Among elite university female soccer players, the players who presented more increased asymmetry of kinetic characteristics of jumping, also showed weak sprinting performance. Moreover, the players presented the best performance in velocity of the jumping variables and also had the best sprinting performance. Coaches and players should focus on keeping inter-limb balance and developing jumping velocity to improve sports performance. In future, the cause-and-effect relationship between jumping and sprinting should be identified.

The Association between Bilateral Deficit and Athletic Performance: A Brief Review

An abundance of information can be found in the scientific literature regarding the bilateral deficit (BLD) in different contraction types, including its possible underlying mechanisms. On the other hand, studies on the relationship between BLD and athletic performance have only begun to emerge in recent years. The purpose of this review article is to assemble and analyze the literature on the topic of the relationship between BLD and athletic performance. After a detailed review of the scientific databases, we analyzed 10 relevant scientific articles. BLD calculated from outcomes of vertical jumps was positively related to the ability to change direction quickly in volleyball, basketball, tennis and student population, but not in soccer. Sprint running performance does not seem to be associated with BLD, while one study suggested that a smaller BLD is associated with a more efficient start in a sprint. Apart from the associations with change in direction performance, there is little evidence to support the association between BLD and athletic performance; thus, further research is required in other sports, incorporating sport-specific performance outcomes and multiple tasks to calculate the BLD.