Squat Jump Research Articles

The Impact of the Soccer Training Season on the Body Composition and Physical Performances of Young Soccer Players

The purpose of this research was to prove the effectiveness of a soccer training program during a macrocycle (preparation and competition season) on the body composition and physical performances of young players. The research was conducted with a sample of 24 soccer players in two age groups: U15 (n=12) and U17 (n=12). The initial testing took place prior to the start of the preseason, whereas the final testing was performed after four months of training. The results prove that the soccer training program for the U15 age range causes important significant differences in the isokinetic force: peak torque flexion and peak torque extension. No significant changes were seen in body composition (body height/mass and muscle and fat mass) or vertical jump (Squat Jump - SJ, Counter-Movement Jump - CMJ, Maximal Counter-Movement Jump - CMJmax). The results also prove that the U17 soccer training program causes important statistical differences in muscle mass, fat mass, SJ, CMJ, CMJmax, and peak torque flexion, but there were no statistically significant changes in peak torque extension or body height/mass of the U17 soccer players. This research shows that the sensitive phase for relevant improvements in explosive force occurs after the age of 15 years, a period that is characterized by the dramatic development of muscle mass.

Conventional video recordings dependably quantify whole-body lifting strategy using the Stoop-Squat-Index: A methods comparison against motion capture and a reliability study

Whole-body lifting strategies could be derived from conventional video recordings using the Stoop-Squat-Index, which quantifies the ratio between trunk forward lean and lower extremity joint flexion from 0 (full squat) to 100 (full stoop). The purpose of this study was to compare Stoop-Squat-Indices derived from conventional video recordings to those from a three-dimensional marker-based motion capture system and to evaluate interrater and intrarater reliability of the video-based approach.Thirty healthy participants lifted a 5-kg box under different conditions (freestyle, squat, stoop). Kinematic data were recorded using a Vicon motion capture system (serving as reference standard) and an iPad camera. Stoop-Squat-Indices over the entire lifting cycle were derived separately from both approaches. Agreement was assessed using mean differences (video minus motion capture) and limits of agreement. Reliability was investigated by calculating intraclass correlation coefficients (ICC) and minimal detectable changes (MDC) over the course of the lifting cycle. Systematic errors were identified with Statistical Parametric Mapping-based T-tests.Systematic errors between the video-based and the motion capture-based approach were observed among all conditions. Mean differences in Stoop-Squat-Indices over the lifting cycle ranged from −6.9 to 3.2 (freestyle), from −1.8 to 5.3 (squat) and from −2.8 to −1.1 (stoop). Limits of agreement were lower when the box was close to the floor, and higher towards upright standing. Reliability of the video-based approach was excellent for most of the lifting cycle, with ICC above 0.995 and MDC below 3.5.These findings support using a video-based assessment of Stoop-Squat-Indices to quantify whole-body lifting strategy in field.

Deep squat test – Functional movement Screen: Convergent validity and ability to discriminate subjects with different levels of joint mobility

BackgroundFunctional Movement Screen (FMS) is an important tool in the assessment of exercise practice. Assuming FMS lacks precise validity for assessing postural deficits, further research is needed to assess whether it is a sufficiently precise tool for analysing joint mobility. Research aims were to evaluate: convergent validity of Deep Squat (DS) – one of FMS tests – regarding joint mobility, using data from a three-dimensional motion analysis as a comparable method; DS's ability to discriminate between subjects with different joint mobility levels. MethodsSixty subjects were selected (23.6 ± 3.8 years). DS was performed according to FMS guidelines. Subjects' performance in frontal and sagittal planes was recorded by two video cameras and subsequently scored by two FMS-certified evaluators. Three-dimensional motion analyses of DS were acquired by a Vicon Motion Capture System (200 Hz). Ten trials were acquired for each subject. Ankle, knee, hip, and shoulder angular positions in sagittal plane were determined from the FullBody PlugInGait model. Spearman's coefficient examined the correlation between angular positions and DS score. Kruskal-Wallis test was used to assess the DS ability to discriminate between subjects with different joint mobility levels by comparing different scores. ResultsNegligible to moderate correlations were found between DS score and angular positions (−0.5 < r < 0.5). Only shoulder angular positions showed differences between score “1” and “2” (p < 0.05). Shoulder and hip angular positions showed no differences between score “2” and “3” (p < 0.05). ConclusionsDS yielded low convergent validity regarding joint mobility and did not show the ability to discriminate between subjects with different joint mobility levels.

Determining the Relationship between Squat Jump Performance and Knee Angle in Female University Students.

The Squat Jump (SJ) test is widely recognized as a reliable test for assessing lower-limb explosive strength. However, uncertainty persists in the literature regarding the optimal starting positions for maximizing vertical jump performance. This uncertainty is exacerbated by a disproportionate focus on athletes in existing studies, with insufficient consideration being given to non-athletic women. To address this gap, this study investigated the influence of leg starting angle on explosive jump height in a homogeneous sample of non-athletic women. Thirty-two female students enrolled in a Sports Science master's degree program at the University of Salerno participated in the study. Descriptive statistics were employed to summarize data on various variables, and Pearson's correlations were calculated to assess the relationship between knee angle in the starting position and achieved jump height. The study revealed that different starting positions had a noteworthy impact on jump height among the participants. A strong negative correlation (-0.701) was identified between Squat Jump elevation and the knee angle in the starting position. Notably, 62.5% of the subjects opted for a starting knee position of approximately 70 degrees, with all of them consistently achieving a jump height associated with this specific angle. These findings provide valuable insights into the relationship between leg starting angle and explosive jump height in non-athletic women. The observed correlation underscores the significance of the starting position in Squat Jump performance. The prevalence of a specific knee angle choice among participants suggests potential implications for training and performance optimization in this sample.

Cluster Method: Effects on Performance in Handball

The aim of this study was to examine the effects of six week traditional and cluster training method applied in female handball players on speed, strength and throwing power. 32 handball players participated in this study. 16 athletes were assigned in the Cluster Training Group (CTG), 16 athletes in the Traditional Training Group (TTG). The training continued for six weeks, three days a week, during the preparation period of the annual training program. Both groups practiced leg extension/flexion, pulldown, butterfly, bench press, deep squat. The CTG performed 80% of repetition maximum (1RM), 4 repetitions with a 20-second rest, total of 12 repetitions and 2 sets. The TTG, on the other hand, performed 80% of 1RM, 12 repetitions, 2-3-minute rest between sets, and again 2 sets. At the beginning and end of the training, 10 and 20 m speed, hand grip strength, standing long jump, vertical jump, throwing speed, squat and bench press performance measurements were recorded. A statistically significant difference was found in the performance values within the group (p&amp;lt;0.05). A statistically significant difference was found between groups in the vertical jump and standing long jump (p&amp;lt;0.05). There was no statistically significant difference between groups in terms of the other performances (p&amp;gt;0.05). As a result, it was seen that the cluster method was effective on the development of the jump force. Considering the difference between cluster and traditional training methods, we can say that the cluster method provides more advantages than the traditional method in branches that require explosive strength.

Pengaruh Latihan Squat Jumps Skater Hops Dengan Jump Forheight Ins and Outs Terhadap Kekuatan Dan Power Otot Tungkai

This study aims to evaluate the effect of squat jumps and skater hops with jump for This research is intended to evaluate or assess the impact of squat jumps and skater hops training with jumps for height and ins and outs on increasing leg muscle strength and explosive power. The research method applied is quantitative treatment or quasi-experimental research with a randomized group pre and post test design. Research subjects were divided into three groups, where each group consisted of 11 people. Group 1 received training treatment combining squat jumps and skater hops, group 2 received training treatment combining jumps for height and ins and outs, while group 3 underwent training according to the extracurricular (conventional) program. The duration of the training was 6 weeks. The instruments used involve a leg dynamometer as a test instrument to measure leg strength and jump MD to measure jump height. Analysis of the paired sample t-test showed that each group experienced a significant increase (p&lt;0.05) in both the strength and power variables. The results of the MANOVA analysis showed a significance value of less than 0.05 (p &lt;0.05), indicating that there were significant differences in group 1, group 2 and group 3 in increasing strength and power. The conclusion of this research is that each group can increase strength and power, while there are significant differences between group 1, group 2, and group 3 in increasing strength and power.

Effects on strength, jumping, reaction time and perception of effort and stress in men´ s top-20 World Padel Competitions

Paddle tenis has experienced significant growth in recent years, becoming one of the most popular and globally expanding sports. This study aims to examine the physiological performance and subjective perception of stress and fatigue in top-20 padel players during matches. Seven elite players participated in the study. Various variables were evaluated, such as subjective perception of effort and stress, isometric grip strength, reaction time, and jump performance, both before and after the matches. The results showed significant increases in subjective perception of effort, perceived stress, and performance in vertical countermovement and squat jumps, as well as in horizontal jumps after the matches. However, no significant changes were observed in reaction time, free-arm jumps, and grip strength (although significant differences were observed between the dominant and non-dominant hand). These findings suggest that the physical conditioning of high-level padel players allows them to endure the fatigue of matches. The differences between the dominant and non-dominant hand indicate asymmetries due to the one-sided nature of this sport. Reaction time did not decrease, suggesting that the level of fatigue was not sufficient to limit the information processing of these athletes. Perceived stress, with widely dispersed values far from the maximum, was consistent with the reaction and adaptation times of the players. The repeated decelerations and accelerations from the backcourt to the net (and vice versa) did not produce excessive fatigue but rather muscular activation, which was evident in horizontal jumps. These findings contribute to understanding the physiological aspects of padel and can be used for the development of training programs that optimize performance and minimize the perception of fatigue in players.

Velocity-Specific Relationships Among Eccentric and Concentric Force Velocity Profiles and Jumping Performance

The purpose of this study is to determine the relationships among force velocity profiles during eccentric only movements (eFVP), concentric only movements (cFVP), and dynamic performance during a countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ). Nineteen collegiate baseball players (1.85 ± 0.04 m, 86.4 ± 8.2 kg, 21.1 ± 1.8 years) from a single NCAA Division I team performed CMJ, SJ, and DJ, drop landings from varying heights, and hex bar jumps with varying weights. FVPs were created with a linear regression using the drop landings for eFVP and hex bar jumps for cFVP, which were used to calculate slopes and area under the entire FVP and velocity-specific regions. Correlations analyzed the results with bootstrapping for 95% confidence intervals. Area under eFVP correlated with cFVP at r=0.51 (p&lt;0.05), cFVP slope presented strong correlations with CMJ height and DJ height while eFVP slopes did not relate to jumping performance or metrics. Area under the faster regions of cFVP and eFVP produced moderate and strong relationships to jumping performance. The area under the FVP, especially when separated into velocity-specific bands, may be a key metric which can audit or provide insight into velocity-based training program effectiveness and athlete comparisons.

Evaluating the Efficacy of Eccentric Half-Squats for Post-Activation Performance Enhancement in Jump Ability in Male Jumpers

The purpose of the present study was to investigate effect of post-activation performance enhancement (PAPE) induced by the eccentric half-squat exercise on vertical jump performance in male jumpers. The jumping height, peak power, and work were measured and evaluated in twenty male jumpers (age: 21.2 ± 1.7 years, height: 191.1 ± 3.3 cm, body mass: 81.56 ± 7.3 kg) who participated in the national championship last year. Participants performed five eccentric half-squats at 85% of their one-repetition maximum (1 RM), with a knee angle below 90°, followed by immediate and 2 min delayed jump assessments using the Squat Jump (SJ) and Countermovement Jump (CMJ) tests. Results showed that this specific PAPE protocol did not significantly improve jump performance for the SJ (Height: ES = 0.613, p = 0.462, Work: ES = 0.124, p = 0.231, Power: ES = 0.382, p = 0.125) or CMJ (Height: ES = 0.523, p = 0.368, Work ecc: ES = 0.133, p = 0.505 (only main effect time p &lt; 0.05), Work con: ES = 0.114, p = 0.101, Power ecc: ES = 0.134, p = 0.177, Power con: ES = 0.182, p = 0.195, Leg stiffness: ES = 0.095, p = 0.358) tests. Factors such as stimulus specificity, rest intervals, muscle length, and the balance between potentiation and fatigue may explain these results. This study highlights the complexity of PAPE responses and suggests that a single set of eccentric squats with a short rest may not improve jump performance in male jumpers. Further research is required to optimize the interplay between conditioning stimuli and rest periods to maximize PAPE effects in athletic performance enhancement.

In the Driving Seat with High-Resolution Ano-Rectal Manometry

Introduction: High-resolution ano-rectal manometry (HRAM), part of the investigative process to diagnose disorders of recto-anal co-ordination, is currently performed in the left-lateral position (LLP). This may seem unnatural for patients and recent data suggest that the seated, squatted position (SP) may improve rectal drive and recto-anal pressure gradients, raising the question as to whether defaecatory dyssenergia (DD) is over-diagnosed when the test is carried out in the LLP. Aim/method: A single centre study was carried out in patients with faecal incontinence and/or constipation to evaluate the effect of SP versus LLP on HRAM analysis and resultant manometric diagnosis of DD. Positioning was consecutive and the order was randomised for each patient. The HRAM protocol was carried out in accordance with the manufacturer’s guidelines (Manoscan). Data analysis and interpretation were blinded with a consensus reached for each test position. Data (mean ± SEM) were analysed using an unpaired t-test and Chi-square test. Results: In total, 40 patients completed the study, including 33 females with a median age of 56 (IQR 48–63). The mean rectal drive was significantly higher in the SP vs. LLP (82.6 ± 5.3 mmHg vs. 44.1 ± 3.9 mmHg, respectively, p &lt; 0.0001). No difference in the anal sphincter relaxation pressure (66.7 ± 5.7 mmHg vs. 70.9 ± 5.5 mmHg, p = 0.9535) was detected. The manometric diagnoses of abnormal ano-rectal co-ordination were significantly higher in the LLP, when p = 0.013. Patients reported a significant preference for the seated position, when p = 0.0001. Conclusion: These data show that HRAM in the seated position improves rectal drive, which reduces manometric diagnoses of abnormal ano-rectal coordination. These findings may have important implications for practice and may inform future guidelines.

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

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

FUNCTIONAL MOVEMENT SCREEN (FMSTM) AND BALANCE IN BODYBUILDERS DURING THE DEFINITION PERIOD

The functional movement and balance performances of bodybuilders and the relationship between them arouse curiosity in the definition period where intense restrictions are experienced. The aims of this study were to (a) determine functional movement screening (FMSTM) and balance performance in bodybuilders during the definition period and (b) examine the relationship between these tests. Twelve adult male bodybuilders voluntarily participated in the study. Participants performed flamingo balance test for static balance, upper &amp; lower quarter Y-balance test (YBT-LQ &amp; YBT-UQ) for dynamic balance, and FMS TM tests (deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, and rotary stability) for functional movement screening. There was a significant negative correlation between dominant leg static balance and rotary stability (r=-.832, p=.040) and a significant positive relationship between dynamic balance and rotary stability in dominant and non-dominant leg (dominant leg: r=.589, p=.044, non-dominant leg: r=.775, p=003). There was no significant relationship between YBT-UQ composite scores and FMSTM composite scores on both sides in bodybuilders during the definition period. As a result, the FMS TM score is quite low in bodybuilders during the definition period, and the increase in static and lower extremity dynamic balance performance may increase the rotary stability score. Bodybuilders are recommended to practice lower extremity static and dynamic balance exercises in addition to training during the definition period.

Beyond Belief: Exploring the Alignment of Self-Efficacy, Self-Prediction, Self-Perception, and Actual Performance Measurement in a Squat Jump Performance-A Pilot Study.

It is widely accepted that athletic performance emerges from a complex interaction between physical and cognitive features. Several studies highlighted self-efficacy (SE) in the cognitive domain of athletic performance, but no studies have correlated SE with sport-specific tasks. According to Bandura, this study explored SE and its relationship with self-prediction (SP), self-perception (PSJ), and actual performance in a squat jump (SJ). Thirty-nine healthy collegiate students were assessed using an SE questionnaire, an SP measurement tool, and a validated optical system for actual SJ performance. An SE score and an SE esteem index (SEE) were determined. The alignment between an individual's SP of their SJ performance and their SE beliefs was also examined. The data revealed a significant correlation between SE score and both SJ (r = 0.432; p = 0.006) and SP (r = 0.441; p = 0.005). Furthermore, disparities among the actual SJ, SP, and SEE were statistically non-significant, implying a congruence between self-belief and performance. With a deeper understanding of the interaction between SE, SP, and sport-specific tasks, sports professionals could develop targeted interventions to enhance athletes' overall athletic achievements and apply SE as a feature linking physical and cognitive athletic performance.

Changes in eccentric utilization ratio, reactive strength index and leg stiffness in highly trained sprinters between training phases

Purpose: To determine changes in eccentric utilization ratio (EUR), reactive strength index (RSI), squat jump (SJ) and countermovement jump (CMJ) parameters in elite sprinters from the preparation phase to the competition (indoor) phase.Methods:Ten elite-level sprinters (n=10) were examined. All sprinters performed the SJ, CMJ and 10/5 rebound jump (RJ) tests. Body composition analysis was assessed using dual X-ray absorptiometry (DXA) method. A paired t-test was performed to determine statistical significance.Results:SJ height and relative peak power increased significantly from 43.10 ± 6.1 cm to 46.30 ± 5.7 cm (P= .013, Cohen’s d= .98) and from 52.62 ± 4.5 W·kg BM-1 to 55.55 ± 4.5 W·kg BM-1 (P= .017, d= .92) respectively. CMJ height and relative peak power increased significantly from 46.78 ± 6.1 cm to 49.18 ± 5.5 cm (P= .039, d= .76) and from 55.53 ± 4.1 W·kg BM-1 to 57.92 ± 4.0 W·kg BM-1 (P= .024, d= .86) respectively. No significant differences were observed in RJ performance parameters.Conclusions:SJ and CMJ height, flight time and peak power output per body mass increased in elite sprinters from the preparation to the competition phase while RSI, EUR and leg stiffness (LS) values did not. SJ and CMJ performance can be used as markers of training phase changes in elite sprinters. EUR should be used cautiously to determine training status in elite sprinters since sprint training encompasses reactive strength training all year round. Reactive strength levels via RSI and stiffness levels should be assessed individually in each training phase to determine whether the measured value of these parameters is satisfactory to optimize competition readiness. LS levels should not be compared to general guidelines but rather individually to the athletes’ sprint performance and then training should be adjusted accordingly.

A comparative study of lower limb strength during vertical jump of male college students in table tennis, badminton and tennis

The objectives of this paper are to explore the correlation of kinetic indices of SJ (squat jump) and CMJ (counter-movement jump) and the differences of lower limb strength mechanics indexes of table tennis, badminton and tennis players under SJ and CMJ. This study included 60 male collegiate athletes, 20 each from table tennis, badminton, and tennis. Subjects performed SJ and CMJ tests on a force platform and the vertical jump data were analyzed. Table tennis, badminton and tennis players demonstrated significant differences in the SJ and CMJ assessments. Badminton players outperformed table tennis players in terms of peak power (PP) (p = 0.005) and peak velocity (PV) (p = 0.017). Badminton players beat table tennis players in PV (p = 0.028), PP (p = 0.022), fast twitch fibers (FTF) (p = 0.033) and pre-stretch effect (EP) (p = 0.0004). Tennis players exhibited lower peak force (PF) (p = 0.006) indicators than badminton players. For athletes in all three sports, the SJ test markers (vertical jump displacement, PF, PP and PV) demonstrated a strong positive correlation. There was a highly significant positive correlation between VJD and PF, PP, PV and FTF among badminton players. Significant positive connections were discovered between PF, PP, PV, FTF and EP, as well as between PP and PV and FTF and EP. PV and FTF had a very strong positive correlation, as did EP, PV and FTF. College badminton players had higher vertical jumps than table tennis and tennis players. In addition to vertical jump height, PP (power production), PV (power velocity) and FTF (force-time factors) are important markers for assessing the success of vertical jumps in athletes’ daily training. These findings can assist coaches and athletes develop better vertical jump training programs.

Validity and reliability of a single-beam sensor for assessment of jump performance

This study aimed to establish the validity and reliability of a single-beam sensor for assessment of jump performance. Thirty-four male and female university students (age: 21.47 ± 0.98 years; height: 173.97 ± 9.32 cm; weight: 70.03 ± 10.63 kg) executed three trials of countermovement jump (CMJ) and three trials of squat jump (SJ), respectively. CMJ and SJ were simultaneously recorded using a force platform (reference) and single- beam jump sensor (Jump Pro). The flight time (FT) and jump height (JH) for both jumps were utilized for analyses. Results revealed the following for FT in CMJ performance: 1) Pearson’s correlation coefficient (r) with lower limit (LL) and upper limit (UL) = 0.90 (0.82, 0.94); 2) Typical error of estimate (TEE) with LL and UL = 0.03 (0.01, 0.02); 3) Bland-Altman estimate = 0.05; and 4) Intraclass correlation coefficient (ICC) = 0.80. On the other hand, JH in CMJ posted: 1) r = 0.96 (0.94, 0.98); 2) TEE = 2.07 (1.73, 2.62); 3) Bland-Altman estimate = 4.00; and 4) ICC = 0.71. In regards to FT in SJ, r = 0.96 (0.94, 0.98), TEE = 0.02 (0.01, 0.02), Bland-Altman estimate = 0.03, and, ICC = 0.88. Further, JH in SJ exhibited r = 0.96 (0.94 – 0.98), TEE = 1.84 (1.53, 2.32), Bland-Altman estimate = 3.55, and ICC = 0.86. These findings support Jump Pro as a valid and reliable tool for measurement of CMJ and SJ performances.

Effects of Training With Different Hang-Power-Clean Intensities on the Maximum Dynamic Strength, Vertical Jump, and Sprint Performance of Female Handball Players.

To compare the effects of 7weeks of training with different hang-power-clean (HPC) intensities on the maximum dynamic strength, vertical jump, and sprint performance of female handball players. Professional handball athletes with at least 1year of HPC experience volunteered to participate. The athletes were balanced by position and randomly assigned to a group with HPC at 90% (HPC90%) or 50% (HPC50%) of HPC 1-repetition maximum (1RM). The training volume was equalized between groups. Pretraining and posttraining assessments included 1RM HPC, jump height in the squat jump (SJ) and countermovement jump(CMJ), and sprint speeds at 5, 20, and 30m. From pretraining to posttraining, both groups significantly increased (P ≤ .05) 1RM HPC, although a small effect size was observed in favor of HPC90%. HPC90% and HPC50% did not induce significant changes (P > .05) in the SJ and CMJ height, although for the SJ, a small effect size was observed in favor of HPC90%. Both groups induced a significant improvement (P ≤ .05) in 5-, 20-, and 30-m sprint speeds, although for all speeds, small to moderate effect sizes were observed in favor of HPC90%. Both training groups induced significant improvements in 1RM HPC and sprint speeds, whereas no significant changes were observed in vertical jumps. In addition, based mainly on the effect sizes, the HPC90% group was more effective for increasing 1RM HPC, SJ, and sprint speeds than the HPC50% group.

Effects of Repeated Jump Testing and Diurnal Changes on Subsequent Countermovement Jump and Squat Jump Output and Force-Time Characteristics

Abstract Harrison, PW, James, LP, Jenkins, DG, Holmberg, PM, and Kelly, VG. Effects of repeated jump testing and diurnal changes on subsequent countermovement jump and squat jump output and force-time characteristics. J Strength Cond Res 38(1): 174–179, 2024—The aim of this brief study was to investigate the effects of repeated jump testing on performance over 2 consecutive days while considering the possibility of diurnal changes. Fourteen male subjects and 14 recreationally active female subjects completed countermovement jump (CMJ) and squat jump (SJ) testing on 5 occasions (baseline [0,800], 5 minutes [0,820], 8 hours [1,600], 24 hours [0,800], and 32 hours [1,600]) over 32 hours. An additional rested baseline test was conducted on a separate day in the afternoon (1,600) to compare jump performance between morning and afternoon baseline values. Excluding small decreases in CMJ height at 24 hours (p = 0.292, Cliff’s delta = −0.225) in male subjects and similar decreases in CMJ height at 5 minutes (p = 0.034, Cliff’s delta = −0.245) in addition to SJ height:contraction time at 32 hours (p = 0.126, Cliff’s delta = 0.153) in female subjects, findings generally showed no changes in jump performance over multiple assessments. Squat jump metrics may have showed small improvements between morning and afternoon baseline values in male subjects (SJ height:contraction time [p = 0.030, Cliff’s delta = 0.225]) and female subjects (SJ height [p = 0.013, Cliff’s delta = 0.173] and SJ height:contraction time [p = 0.091, Cliff’s delta = 0.163)]. As jump performance was largely unaffected by repeated jump testing, the present findings support the use of monitoring practices and research designs that require multiple jump assessments within acute periods (∼32 hours).

Comparative analysis of standard and contrast elastic resistance band training effects on physical fitness in female adolescent handball players.

This study aimed to compare the effects of two elastic band 10-week training programmes on the athletic performance in adolescent female handball players. Participants aged 16.0 ± 0.5 years were randomly assigned to control (CNT, n = 12), standard elastic band (SEB, n = 12), or contrast elastic band (CEB, n = 12) programmes, each performed twice a week supplementing the regular training. The sprint (10 m and 20 m), modified Illinois change-of-direction test (COD), squat jump (SJ), countermovement jump (CMJ), standing long jump (SLJ), back extensor strength (BES), medicine ball throw (MBT), 1-RM bench press, 1-RM half squat, repeated sprint ability, and force-velocity (F-V) tests were measured before and after the intervention. Both CEB and SEB similarly improved sprint (p < 0.01 and p < 0.01) and COD (p < 0.001 and p < 0.01) when compared to CNT. Jumping performance improved significantly (SJ p < 0.01; CMJ p < 0.05) only in CEB, compared to CNT. Strength improved in both experimental groups (p < 0.01; ES: 0.73 < d < 1.59) compared to CNT, and there was a greater increase for CEB than SEB (p < 0.05) in the medicine ball throw (Table 3). Both CEB and SEB increased all RSA scores compared to CNT (p < 0.01; ES: 0.10 < d < 1.22), without significant difference between them. All F-V scores increased significantly in CEB and SEB compared to CNT (p < 0.01; ES: 0.45 < d < 2.47). In addition, CEB showed substantial gains in performance for PPabs, PPrel, and F0 (p < 0.001, p < 0.001 and p < 0.05, respectively) compared to SEB. Ten-week elastic band training conducted within the competitive season improved limb strength, power and F-V profile in female handball players, with a superior effect of the contrast elastic band training mode for upper-limb strength and F-V characteristics.

Morning-evening differences of short-term maximal performance and psychological variables in female athletes.

The aim of this study was to examine the effect of time of day on short-term maximal performance and psychological variables in young females. Fifteen active women participated in the study (age: 22 ± 3years) and completed Hooper and the POMS-F questionnaires subsequently. In a randomized order, they performed a maximum of 30s cycling exercise at two different times of day: in the morning at 07:00h and in the afternoon at 16:00h with a recovery period of 48h. The digit cancellation test, countermovement jump (CMJ), squat jump (SJ) test, and the lower quarter Y balance test were performed at the beginning and at the end of each session. Our results showed that only peak power and mean power (p < 0.01) during the maximum 30s cycling, reaching distances during the Y-balance (p < 0.05), Jump height in CMJ and SJ (p < 0.01) as well as attention, vigor, and stress scores (all p < 0.01) were higher in the afternoon than in the morning. Our results indicated a daily diurnal variation in short-term maximal performance and mood states in young athletic women with better performance observed during the afternoon.