Anthropometric, neuromuscular, physiologic and training variables as determinants to laboratory cycling performance

BACKGROUND

The goal of this study was to verify whether anthropometric, physiological and neuromuscular factors, as well as training characteristics, could predict cycling performance during maximal incremental and time-to-exhaustion tests.

METHODS

Twenty cyclists were evaluated: Anthropometric variables, knee extensor muscle activation and architecture, training history, and training volume were assessed. Second ventilatory threshold (VT2), maximal oxygen uptake (VO2MAX), and maximal power output (POMAX) were assessed during the incremental test. Muscle architecture of the vastus lateralis (VL) and rectus femoris (RF) muscles was evaluated bilaterally to calculate the mean thighs' muscle thickness, pennation angle and fascicle length, at rest condition. After that, time-to-exhaustion test at POMAX was performed. Muscle activation of the VL, RF and vastus medialis (VM) was evaluated of both legs.

RESULTS

Cyclists' height (r2=0.37), experience time and training volume (r2=0.46) were predictors of POMAX (P<0.02), while cadence (r2=0.30) was the only predictive variable for the time-to-exhaustion performance (P<0.01).

CONCLUSIONS

These results suggest that training characteristics and experience are important when training for incremental cycling conditions, whereas cadence (and its determinant variables) should be looked at during maximal and exhaustive conditions.

Strength and Conditioning (S&C) Practices of Judo Athletes and S&C Coaches: A Survey-Based Investigation

ABSTRACT

Weldon, A, Cloak, R, Kirk, C, Ruddock, A, Langan-Evans, C, Detanico, D, Loturco, I, and Kons, R. Strength and conditioning (S&C) practices of judo athletes and S&C coaches: A survey-based investigation. J Strength Cond Res 38(4): e160-e173, 2024-The benefits of strength and conditioning (S&C) for improving judo performance and reducing injuries have been widely studied. However, the S&C practices used and perspectives held by those delivering S&C have yet to be elucidated. Therefore, this study investigated the S&C practices and perspectives of judokas and S&C coaches working within judo. Forty-two judokas and 9 S&C coaches completed an online survey comprising 6 sections: (a) written informed consent; (b) background information; (c) education, qualifications, and prescription; (d) views on S&C; (e) exercise selection; and (f) issues and improvements. Frequency analysis was used to report responses to fixed-response questions and thematic analysis for open-ended questions. Results indicated that S&C coaches were primarily responsible for delivering S&C programs (60%), and S&C information was predominantly sourced from S&C coaches (43%). Strength and conditioning was deemed very important for randori (78-88%), overall judo performance (67-79%), and judo fitness (62-78%). Similarly, S&C was considered very important for the development of speed and power (76-89%), strength (71-89%), and injury reduction (69-78%). Novel findings were also observed, such as integrating judo-specific training within S&C practice, which may be partly explained by more S&C coaches holding judo belts (67%) than S&C qualifications (11%). This study supports practitioners delivering S&C in judo by offering a base of information to critique or align with their existing S&C practices and perspectives. Furthermore, our results may help identify potential gaps between methods used, proposed guidelines, and actual practice, facilitating the development of research and education resources tailored to the current climate.

Variability Analysis in Judo Para Athletes With Visual Impairments: Match-Outcome Performance in the Tokyo 2020 Paralympic Games With Evidence From the New Classification System

Match-related performance analysis in judo Para athletes with visual impairments is important to coaches and staff to identify technical-tactical profiles of their athletes and opponents but also to identify whether there are similar characteristics in each visual class. Thus, this study explores the match-related performance in judo Para athletes and verifies the relationship between performance using the old and new classification systems. The match-derived variables were analyzed using different statistical methods considering a total of 182 matches from the Tokyo 2020 Paralympic Games. The results indicated that performance was affected by sex and degree of impairment. The new classification system seems suitable for grouping Para judo athletes, as it differentiates performance between the two proposed classes (J1 and J2), since athletes from each group compete separately. Furthermore, different variability index measures were correlated with competitive performance, demonstrating a specific performance profile for each sport class in judo.

Effects of stretch-shortening cycle fatigue protocol on lower limb asymmetry and muscle soreness in judo athletes

This study aimed to analyse unilateral countermovement jumps (CMJ) performance and muscle soreness in lower limbs, as well as to compare lower limb asymmetry over 48h after a stretch-shortening cycle (SSC) fatigue protocol. Fourteen judo athletes performed unilateral CMJ on each leg before, and after the 5th and 10th sets over 24h and 48h of an SSC-fatigue protocol. The SSC protocol reduced CMJ performance after the 5th set and 10th sets, especially in the weaker limb (p < 0.05), but returned to the baseline values after 24h. Asymmetry increased for peak force, peak power, and mean power after the 5th set compared to the baseline (p < 0.05) and remained higher for peak force after the 10th set (p = 0.019), returning to the baseline values after 24h (p < 0.05). Soreness increased for the lower body at post, 24h, and 48h compared to the baseline (p < 0.05). In conclusion, a fatiguing SSC protocol can result in increased bilateral asymmetries in judo athletes, but after 24h and 48h of the protocol the bilateral asymmetry returned to the baseline values, with only muscle soreness still elevated.

Bilateral deficit in the countermovement jump and its associations with judo-specific performance

This study aimed to describe the bilateral deficit (BLD) during the countermovement jump (CMJ) in judo athletes and determine the relationship between the BLD and judo-specific performance. Fourteen male judo athletes participated. Athletes performed three specific judo tests, Maximal Sprint Speed Judo Test, Maximal Aerobic Speed Judo Test and Special Judo Fitness Test (SJFT), and double- and single-leg CMJ. The following CMJ variables were used: jump height (JH), mean (MPO) and peak (PPO) power output, peak force (PF), peak velocity (PV) and impulse (IMP). The Pearson's or Spearman's test were used (p < 0.05). The results show that the BLD is found in all CMJ parameters (20 to 31%). Negative correlations between first set of SJFTTT (total throws) and BLD in PF (r = -0.60; p= 0.022) and between the second set of SJFTTT and BLD in MPO (r= -0.74;p = 0.002), PV (r =-0.59;p = 0.025) and IMP (r =-0.55; p = 0.040) were found. Also, negative correlations between SJFTTT and the BLD in all CMJ parameters (r= -0.53 to -0.85; p < 0.05) were found. Higher values of BLD are related to poor SJFTTT performance.

Participation in the International Judo Federation World Tour competitions and performance in Tokyo Olympic Games

Introduction

The International Judo Federation introduced a ranking system in 2009 that determines top athletes for the Olympic Games and seeds them in competitions. Previous research indicated that this ranking list and past performances predicted 19%-27% of performance in the Olympic Games and World Championships. However, due to the COVID-19 pandemic, the relationship between Judo World Tour competitions and Olympic Games performance may have been affected. This study aimed to examine the relationship between athletes' performance in Judo World Tour competitions and their competitive performance at the Olympic Games.

Methods

Data from 393 athletes who participated in the Tokyo Olympics were analyzed considering both long and short-term performance measures. Pearson correlation was used to determine the relationship between variables and multiple linear regressions were used to predict performance for each sex and the entire sample.

Results

The results revealed a range of magnitudes in the correlation between variables, varying from small to large. In terms of regression analyses, it was observed that, for females, the percentage of matches won during the classification period and competition in the year prior to the Olympic Games predicted 37% of their performance. For males, the percentage of matches won during the classification period and competition in the six months before the Olympic Games predicted 36% of their performance.

Discussion

Thus, athletes' quality and reduced exposure to competition near the Olympic Games appear to be important factors in their performance at the event.

Physical performance and somatic maturity in male and female judo athletes: An analysis in different age categories

BACKGROUND

Maturity status is an important parameter to understand physical performance in young judo athletes, especially considering different age categories.

OBJECTIVES

The aim of this study was to investigate the role of each age category (U13, U15, and U18) on physical performance between and within the age groups.

METHODS

Sixty-five male athletes from the U13 (n = 17), U15 (n = 30), and U18 categories (n = 18), and 28 female from the U13 (n = 9), U15 (n = 15), and U18 categories (n = 4) participated in this study. The assessments were performed at two moments separated by 48 h and included anthropometric measurements and physical tests (standing long jump, medicine ball throw, handgrip strength, Special Judo Fitness Test, and Judogi Grip Strength Test). The athletes also provided their date of birth and judo experience. One-way analysis of variance and Pearson correlation were used with significant level set at 5%.

RESULTS

The main results showed higher values of somatic variables (maturity status and body size) and physical performance in the U18 compared to U15 and U13 in male and female (p < 0.05), but no differences between U15 and U13 (p > 0.05). In general, training experience, chronological age, and somatic variables were correlated (moderate to very large magnitude) with physical performance in all age categories for male (r = 0.40-0.66, p < 0.05) and female groups (r = 0.49-0.73, p < 0.05).

CONCLUSION

We concluded that U18 athletes showed higher values of somatic maturity, training experience, and physical performance compared to U13 and U15 categories, with no differences between U13 and U15. In general, training experience, chronological age, and somatic variables were correlated with physical performance in all age categories.

Paratriathlon Race Performance in High-Level Athletes With Visual Impairments: A Retrospective Analysis

OBJECTIVE

The aim of this study was to compare time-trial performances in elite paratriathlon athletes, according to visual classes, sex, and medal distribution.

DESIGN

The data were acquired from official books on Para Triathlon World Cups (2018-2020). The sample included 150 athletes with visual impairment, in classes: PTVI1, PTVI2, and PTVI3. One-way analysis of variance, the Student t test, and χ 2 were used to compare the performance variables and association between visual impairment classes and distribution of medals within different visual impairment classes.

RESULTS

Sex comparisons demonstrated better performance for male athletes compared with female athletes ( P < 0.05). In the sex-specific analysis, only cycling velocity was higher for female, being lower for PTVI1 compared with PTVI3 ( P = 0.012). In visual impairment class results, the first transition time was higher for PTVI1 compared with PTVI2 ( P = 0.050) and PTVI3 ( P = 0.027) and, in the second transition, higher for PTVI1 compared with PTVI2 ( P = 0.001). The χ 2 test showed a higher percentage of gold medals for PTVI3 athletes considering the whole group ( P = 0.050).

CONCLUSIONS

These results indicate that male athletes have better performance than female athletes. PTVI1 female athletes showed lower cycling velocity compared with PTVI3. Considering both male and female groups, blind athletes presented higher transition times and a lower percentage of medals.

Tactile and Auditory Stimuli Can Improve the Specific Physical Performance of Para-Judo Athletes With Varied Origins of Visual Impairment

Our aim in this study was to compare performance adaptations based on tactile or sonorous stimuli in para-judo athletes with congenital or acquired visual impairment. Twenty judo athletes with a type of visual impairment performed both the adapted Special Judo Fitness Test (SJFT) with tactile and sonorous stimuli and the standard SJFT. We used two-way ANOVA with repeated measurements in the second factor to compare the SJFT performance of athletes with visual impairment between two groups (acquired or congenital) in the two test situations, with the level of significance set at p < .05. Both groups of participants performed better on the adapted SJFT with tactile and sonorous stimuli compared to the standard condition on number of throws (p = .029 and p < .001) and showed lower final and post 1-minute heart rates (HR) (p < .05). There were no group differences in performance on any SJFT adaptations (p > .05). Thus, both SJFT adaptations (tactile and sonorous stimuli) enhanced the judo-specific performance of athletes with both acquired and congenital visual impairments. However, athletes with either origin of impairment showed a better HR in the adaptive tactile stimuli testing compared to the standard SJFT testing condition.

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.

Percurso docente: identificando a construção de conhecimentos para o ensino em disciplinas de lutas

O objetivo deste estudo foi averiguar o percurso docente e identificar a construção de conhecimentos de professores universitários para o ensino em disciplinas de lutas. Trata-se de um estudo descritivo com abordagem qualitativa, no qual participaram do estudo sete professores de ensino superior que lecionam disciplinas com a temática investigada em cursos de licenciatura em Educação Física. Como técnica de coleta de dados foi utilizada a entrevista narrativa. A análise dos dados ocorreu mediante a técnica de análise de conteúdo, com categorias organizadas tanto a priori (percurso formativo e profissional) quanto a posteriori (envolvimento com as lutas e conhecimentos sobre o conteúdo lutas). Os resultados apontaram o envolvimento com modalidades de lutas nas trajetórias, e alguns participantes consideram a experiência pela prática de modalidades de lutas um conhecimento importante para o ensino. Os professores apresentaram como limitações não possuir expertise em lutas, a carência de bibliografia sobre o ensino das lutas, e não ser professor titular da disciplina. Por outro lado, os resultados perspectivaram olhares para além do ensino da técnica, por meio de aspectos históricos, sociais e estratégias voltadas ao jogo. No estudo, foi possível mencionar pautado na teoria da “base de conhecimentos para o ensino” que os professores tendem a considerar os diversos conhecimentos para subsidiar o ensino, porém, ainda carecem refletir sobre sua trajetória e aprimorar e transformar suas bases de conhecimentos, visando um ensino que rompa com as problemáticas apontadas pela literatura e pelos participantes.

More time for judo matches? Analysis of type of techniques, time, scores, and penalties in the Tokyo 2020 Olympic Games

This study aimed to analyze the distribution of judo matches in the Tokyo 2020 Olympic Games, considering matches in the regular duration (≤4 min) and during the extra time (the golden score) according to sex, scores, penalties, phases of competition, weight categories, and judo techniques. The data were extracted from the Official Results Books of the Olympic Games in Tokyo 2020. The combats were divided in matches that were finished in the regular duration and that were finished by the golden score, with a total of 450 matches. The Chi-square test was used to identify the association between all variables and different groups of matches duration, with the level at p < 0.05. The main results demonstrated significant association, considering sex and frequency of matches in the regular time (χ2 = 6.59; p = 0.010) for female athletes. The majority of matches ended in the 3–4 min (χ2 = 204.16; p < 0.001), scores were mostly awarded in the regular time and penalties in the golden score (χ2 = 48.72; p < 0.001), and few matches ended by the golden score for heavyweight athletes (χ2 = 15.16; p = 0.019). Therefore, a high number of matches ended in the golden score in the Olympic Games Tokyo 2020, with a high number of penalties in this competition.

Effects of acute caffeine intake on combat sports performance: A systematic review and meta-analysis

The interest in the benefits of caffeine in combat sports has grown exponentially in the last few years, evidenced by the significant rise of post-competition urine caffeine concentration. We conduct a systematic review and meta-analysis on the effects of caffeine on different performance variables in combat sports athletes. In total, we included 25 studies. All studies included had blinded, and cross-over experimental designs, and we conducted a risk of bias analysis. For nonspecific outcomes, there was an ergogenic effect of caffeine on vertical jump height (SMD: 0.38; 95% CI: 0.04, 0.71) and reaction time (SMD: -0.98, 95% CI: -1.46,-0.50). For outcomes specific to combat sports, there was an increase in the number of throws with caffeine in the Special Judo Fitness Test (SMD: 0.62; 95% CI: 0.14, 1.09). Caffeine ingestion increased the number of offensive actions during combats (SMD: 0.40; 95% CI: 0.06, 0.74). Caffeine ingestion increased the duration of offensive actions during combat (SMD: 0.58; 95% CI: 0.21, 0.96). Finally, caffeine ingestion increased blood lactate concentration after bout 1 (SMD: 1.35) bout 2 (SMD: 1.43) and bout 3 (SMD: 1.98). Overall, athletes competing in combat sports may consider supplementing with caffeine for an acute increase in exercise performance.

Jiu-Jitsu-Specific Performance Test: Reliability Analysis and Construct Validity in Competitive Athletes

ABSTRACT

da Silva Junior, JN, Kons, RL, de Lucas, RD, and Detanico, D. Jiu-jitsu-specific performance test: Reliability analysis and construct validity in competitive athletes. J Strength Cond Res 36(1): 174-179, 2022-The aim of this study was twofold: to analyze the test-retest reliability and sensitivity of Jiu-Jitsu "anaerobic" performance test (JJAPT) variables, and to determine the construct validity of JJAPT by comparing groups of athletes with different levels and technical profiles. Sixty Brazilian Jiu-Jitsu (BJJ) athletes participated in this study. The reliability analysis was performed with all athletes and the construct validity was tested in the group comparisons-novice vs. advanced level and guard versus pass fighters. From the JJAPT, the number of repetitions, rate of perceived exertion (RPE) and average heart rate were assessed over the 5 sets. The test-retest reliability was assessed by absolute and relative analysis for each variable. The construct validity was tested by comparison means and the receiving operator characteristic (ROC) curve was used with the level of significance set at 5%. The main results demonstrated excellent test-retest reliability for all but the RPE in the first sets, with good sensitivity and agreement. The maximal number of repetitions in the JJAPT showed good construct validity, as it showed sensitivity to discriminate the performance between the advanced and novice BJJ athletes (p < 0.001, ROC curve area of 0.95). However, no significant difference was found between the technical profile groups (p > 0.05). We concluded that the JJAPT presents excellent performance reliability as a specific-sport test. In addition, the test presented evidence of construct validity, because it discriminated the performance between the advanced and novice BJJ athletes.

World-ranking performance in judo athletes with visual impairment: An approach considering sport classes and weight categories

The objective of this study was to analyze the ranking scores in Paralympic judo athletes in different visual impairment classifications (B1, B2, and B3) and describe the frequency of athletes of each classification allocated in the first five and last five positions in the ranking list. A total of 488 judo athletes with visual impairment (332 male and 156 female) took part in this study. Data were extracted from the Official Ranking List, documented and organized by the International Blind Sports Federation, and analyzed according to sport classes (B1, B2, and B3) and weight categories. One-way analysis of variance was used to compare the scores among different groups. The main results showed that B1 athletes presented lower total and best scores compared to B2 and B3 counterparts in both female ( p = .020, p < .001, respectively) and male groups ( p = .010, p = .005, respectively). In addition, when analyzing the ranking list position, there was a higher percentage of B1 athletes in the last five positions in female (60%) and male groups (60%) than B2 and B3 athletes. Investigations about classification and competitive system can assist coaches and sports organizations to identify the appropriateness of the ranking system scores adopted for athletes with visual impairment. Our findings showed some issues when considering competitive programming that includes all visual impairment classes in the same category.

Neuromuscular impairment after high-intensity running and vertical jump exercise protocols

BACKGROUND: Repetitive stretch-shortening cycle exercises generate high rates of mechanical work and consequently induce substantial muscular fatigue related to delayed neuromuscular functions. OBJECTIVE: To investigate the neuromuscular impairment after high-intensity exercise protocols involving different gravity loads in stretch-shortening cycle – running (RUN) and vertical jumps (VJ). METHODS: Twenty-two healthy men, divided into two groups, VJ and RUN participated in this study. The individuals performed a training session involving six bouts of 30 s of VJ or RUN. The isokinetic PM (PM) of the knee extensors and flexor muscles, rate of perceived exertion and delayed onset muscle soreness (DOMS) were evaluated at pre, post, 24 h and 48 h post-training. RESULTS: The concentric and eccentric PM of the extensor in the RUN group was reduced until 24 h, while in the VJ a decrement was observed until 48 h. Following running, the PM of the flexors decreased until 48 h, while for VJ there was an eccentric PM decrement at 48 h. The DOMS increased at the anterior thigh and only after VJ training for 48 h. CONCLUSION: Acute and delayed neuromuscular impairment may be observed after both exercise regimens, but high-intensity training using vertical jumps seems to induce a more pronounced impairment than running.

Can the history of injury influence shoulder isokinetic torque parameters in volleyball players?

The aim of the present study was to compare shoulder internal rotator and external rotator isokinetic parameters in concentric and eccentric contractions between volleyball players with and without a history of shoulder injury. Thirty male volleyball players participated of this study, divided into two groups: with a history of injury (WHI) in the dominant shoulder (11 athletes; age: 19.4 ± 3.6 years) and no history of injury (NHI) (19 athletes; age: 18.3 ± 2.9 years). The peak torque (PT) and concentric (Con) and eccentric (Ecc) PT angles in internal (IR) and external rotation (ER) at velocities of 60 and 180°/s were measured. The conventional (Con_ER:Con_IR), functional spiking (Ecc_ER:Con_IR), and cocking ratios (Ecc_IR:Con_ER) were calculated. No significant differences were found between groups for PT and PT angle, or for conventional, functional spiking, and cocking ratios. However, the spiking ratio was considered low (0.87) in the WHI group. Moreover, for the spiking ratio in the WHI group, PT at 60°/s occurred at different angles. We conclude that previous injury in shoulder did not affect the peak torque, as well as conventional, spiking or cocking ratio. However, the PT angles at 60°/s used to calculate the spiking ratio shifted due the prior injury.

Psychometric Suitability of Adaptations to the Special Judo Fitness Test for Athletes With Visual Impairment

This study aimed to test the reliability, sensitivity, construct and logical validity of an adapted Special Judo Fitness Test (SJFT) for judo athletes with visual impairment . Twenty judo athletes with visual impairments performed both the adapted SJFT with tactile and sonorous stimuli (experimental conditions) and the typically administered SJFT (standard condition). We used analyses of variance (ANOVAs) with repeated-measures to compare the groups' SJFT performances, and one-way ANOVAs to compare different visual ability classes of athletes (B1, B2 and B3). We used t-tests to compare SJFT variables between elite and sub-elite groups. We set statistical significance for all tests at p < 0.05. The standard SJFT showed excellent test-retest reliability for number of throws and overall index (ICC = 0.91-0.95), and both sonorous and tactile sensitivity adaptations of the SJFT showed medium sensitivity for detecting performance changes. The number of throws and SJFT index were higher with the sonorous adaptation of the test, compared to the tactile and standard versions (p < 0.001). Athletes who were blind (B1) presented similar performances to athletes who were partially sighted (B2 and B3) only on the SJFT with the sonorous stimulus. Moreover, only the sonorous SJFT adaptation discriminated between the performances of elite and sub-elite athletes (p < 0.001). In conclusion, both SJFT adaptations showed excellent reliability and medium sensitivity on test-retest, but, only the SJFT with the sonorous stimulus seemed valid for assessing judo athletes with varying degrees of visual impairment, and only the sonorous stimulus SJFT discriminated elite from sub-elite athletes.

Effect of vision impairment on match-related performance and technical variation in attacking moves in Paralympic judo

In Paralympic judo for athletes with vision impairment (VI judo) all eligible athletes (i.e. B1, B2 and B3 classes) compete against each other in the same competition. Evidence suggests that athletes with more impairment may be disadvantaged, but that more sensitive measures of performance are necessary to understand the impact of impairment on performance. The aim of this study was to investigate the relationship between Para sport class and technical variation, time-motion variables, and performance in Paralympic judo. All 175 judo matches from the Rio 2016 Paralympic Games were analysed across 129 competitors (82 male and 47 female). The main results indicated that athletes who demonstrated less technical variation also experienced less competitive success, with the functionally blind athletes (class B1) demonstrating less technical variation than partially sighted (class B2 and B3) athletes (p < 0.05). There was no difference in the time-motion variables between sport classes (p > 0.05). We conclude that measures of technical variation are sensitive to differences in impairment and are suitable for studies that investigate the impairment-performance relationship in VI judo. Results further confirm that some athletes with impairment are disadvantaged under the current rules of VI judo.

Effects of successive judo matches on interlimb asymmetry and bilateral deficit

OBJECTIVE

To verify the effects of successive judo matches on interlimb asymmetry and bilateral deficit in judo athletes.

DESIGN

Repeated measures; SETTING: University Judo center.

PARTICIPANTS

Fourteen male judo athletes.

OUTCOME MEASURES

Four simulated matches consisting of 4-min. Before the first match and after each match athletes were submitted to single leg tests - Countermovement Jump (SL_CMJ) and Standing Long Jump (SL_SLJ), and handgrip strength (HGS) in the dominant and non-dominant limbs. Interlimb asymmetry was calculated in both jumps and handgrip strength tests.

RESULTS

Most jump-derived variables did not change the magnitude of asymmetry throughout the matches (p > 0.05), with the exception of jump height asymmetry in SL_CMJ, that increased after the second match (p = 0.001). The HGS decreased in both hands from the first match (p < 0.001), without asymmetry. The highest bilateral strength deficit was observed in post-match 1 and post-match 2 (close to 10%).

CONCLUSION

Four-successive judo matches did not change the magnitude of interlimb asymmetry, with exception of SL_CMJ height, which increased after the second match. The handgrip strength decreased throughout the matches, but similarly in both hands. Finally, the direction of asymmetry showed consistency throughout the matches only for SL_CMJ height.

Rapid weight loss in visually impaired judo athletes: Prevalence, magnitude, and methods

The aim of this study was to determine the prevalence, magnitude, and methods of rapid weight loss (RWL) in visually impaired (VI) judo athletes, and compare these aspects between males and females. Thirty VI judo athletes (20 men and 10 women) completed a validated questionnaire to assess information about the magnitude and methods of RWL. Simple frequency was used to describe the influence and methods in all athletes and according to sex. Moreover, the t test was used to compare the variables between the sexes with the significance level set at p < .05. The main results showed that most VI judo athletes (67%) lost weight to compete. Most methods included gradual dieting (40%) and increased exercise volume (33%). The judo coach/ sensei was the person who most influenced the athletes in RWL (45%). There were no significant differences between the sexes regarding the RWL magnitude and methods used. As concluded, most VI judo athletes lost weight to compete, but the interval to reduce weight seemed slightly longer than it usually occurs in RWL. Gradual dieting and increased exercise volume were the most frequently used methods to lose weight, without any differences between males and females.

Physical Performance in Young Judo Athletes: Influence of Somatic Maturation, Growth, and Training Experience

Purpose: To determine the individual contributions of chronological age, somatic maturation, body size and composition, and training experience as indicators of performance in neuromuscular and judo-specific assessments in young athletes. Methods: Sixty-six youth judo athletes performed anthropometric measurements, neuromuscular tests-standing long jump test (SLJ), medicine ball throw test (MBT), handgrip strength test (HGS), and judo-specific tests-Special Judo Fitness test (SJFT) and Judogi Grip Isometric Strength Test (JGST_ISO). A multiple linear regression was used with the level of significance set at 5%. Results: The main results showed age-peak height velocity (PHV), body fat and training experience explained close to 20% of SJFT performance. Chronological age, age-PHV, height, body mass and body fat accounted for 42% of variance in JGST_ISO. Chronological age, body fat and training experience explained 35% of the variance in SLJ, while chronological age, body mass and body fat explained 53% of the variance in MBT. Finally, age-PHV, body mass and height explained 54% of the variance in HGS. Conclusion: Estimated age-PHV and growth variables explained moderate to large proportions of the variance in neuromuscular tests (with exception of SLJ), while both estimated age-PHV, training and growth variables were predictors of judo-specific performance.

The ratio standard is not adequate for scaling handgrip strength in judo athletes and nonathletes

This study aimed to analyze if the ratio standard or the allometry is the best scaling methods of handgrip strength (HGS) for body mass (BM) in judo athletes and nonathletes, and to verify if the HGS mean values are higher in judo athletes than nonathletes when the BM effect is removed. One hundred forty-two individuals, being 88 judo athletes and 54 non-athletes participated in this study. The maximal isometric HGS was measured in judo athletes and nonathletes in the preferred hand. Only the allometry method was able to remove the BM effect of HGS. The al-lometric exponents found for athletes was b=0.68 and b=0.563 for non-athletes. A common allometric exponent was identified as (b=0.64) for comparing judo athletes and nonathletes. However, neither was able to allow for the comparison between groups due to a distortion of (bias; P<0.01). Thus, an index (HGS_INDEX) was proposed to allow within-group (judo athletes and nonathletes) and between-group (judo athletes vs. nonathletes) comparison, removing the effect of BM. In summary, the allometric exponent based on the theory of geometric similarity (b=0.67) was able to remove the BM effect of HGS in judo athletes. An index (HGS_INDEX) is suggested for classification (or rank) of the judoka in relation to the expected average of HGS.

PREDICTORS OF JUDO-SPECIFIC TASKS FROM NEUROMUSCULAR PERFORMANCE IN YOUNG ATHLETES AGED 11-16 YEARS

BACKGROUND

Physiological capacities are continuously developed throughout childhood and adolescence enhancing physical performance, but the years of formal training also contribute to performance improvements seen in young athletes. Thus, identifying the variables that may predict performance in young athletes is important for monitoring and planning the season.

PURPOSE

This study aimed to identify the predictors of judo-specific performance tasks from neuromuscular tests in young judo athletes.

STUDY DESIGN

Cross-sectional study.

METHODS

Ninety-four young judo athletes: 28 girls and 66 boys (aged 11-16 years) participated in the study. Athletes performed the following neuromuscular assessments: the standing long jump (SLJ), the seated medicine ball throw (MBT) and the measurement of handgrip strength (HGS). They also performed judo-specific tests including the Special Judo Fitness Test (SJFT) and Judogi Grip Strength Test (JGST). Pearson's linear correlation and a multiple linear regression were used with the level of significance at p<0.05.

RESULTS

The main results showed correlations between all neuromuscular tests and the number of throws and index obtained in the SJFT for boys (r = 0.35-0.54, p<0.05) and girls (r = 0.41-0.47, p<0.05). Additionally, the JGST performance was correlated with HGS (r = 0.48, p<0.01) and the MBT (r = 0.38, p = 0.013), but only in boys. The SLJ and HGS predicted close to 30% of the variance in the SJFT performance (p<0.001).

CONCLUSION

Strength and power in upper and lower limbs are related to judo-specific tasks in young judo athletes and can moderately predict the performance in SJFT performance.

LEVELS OF EVIDENCE

2b.

Is Bilateral Deficit in Handgrip Strength Associated With Performance in Specific Judo Tasks?

Turnes, T, Silva, BA, Kons, RL, and Detanico, D. Is bilateral deficit in handgrip strength associated with performance in specific judo tasks? J Strength Cond Res XX(X): 000-000, 2019-The aim of this study was to identify the existence of bilateral deficit (BD) on maximal handgrip strength during standing and seated positions in judo athletes and to correlate this with judo-specific tasks. Nineteen male judo athletes (age 22.1 ± 4.6 years) performed unilateral and bilateral handgrip strength tests in seated and standing postures to calculate bilateral index (BI). Athletes then performed the Judogi Grip Strength Test (dynamic and isometric modes) and Special Judo Fitness Test. The comparisons between bilateral and unilateral handgrip strength for each position, weight categories, or training experience (novice <10 years and advanced >10 years) were made by paired and unpaired t-tests. The sum of bilateral forces was significantly lower than unilateral forces at standing (unilateral: 105 ± 20 vs. bilateral: 102 ± 21 kgf, BI: -3.0 ± 5.9%, p = 0.043), but not at seated position (unilateral: 100 ± 19 vs. bilateral: 98 ± 19 kgf, BI: -2.1 ± 7.3%, p = 0.230), indicating BD only at standing position. Pearson coefficient correlations were not significant between judo tests and BI, with similar performance in judo tests between athletes with BD and bilateral facilitation (p > 0.05). Significant BD was observed at standing position in advanced (-4.5 ± 7.1%, p = 0.049) but not in novice athletes (-0.9 ± 3.8%, p = 0.592). We concluded that BI in maximal handgrip strength test was not related with judo-specific tests. However, the BD occurred only at standing position, suggesting that postural stability may contribute for this phenomenon.

Photobiomodulation Therapy Does Not Attenuate Fatigue and Muscle Damage in Judo Athletes: A Randomized, Triple-Blind, Placebo-Controlled Trial

Fatigue and muscle damage negatively affect performance in lower limb exercises involving the stretch-shortening cycle in judo athletes during competition and training sessions. Photobiomodulation therapy has emerged as an effective non-invasive strategy to attenuate fatigue and muscle damage when applied before different types of exercises. Our objective was to investigate the effects of photobiomodulation therapy on fatigue and muscle damage in judo athletes. Sixteen judo athletes participated in the study (23.1 ± 3.8 years, 77.9 ± 14.9 kg, 173.1 ± 8.9 cm, 17.5 ± 7.3 body fat%, 12.9 ± 5.0 years of practice). Each participant received, in a randomized manner, photobiomodulation in one limb and placebo in the contralateral limb on the same day. Thereafter, subjects performed a stretch-shortening cycle protocol to induce muscle fatigue and damage. Countermovement jump (impulse, peak power, peak velocity, and peak force), echo intensity (rectus femoris and vastus lateralis), and muscle soreness were assessed at different time points before, during, immediately post, and 24 and 48 h after the protocol. Muscle fatigue was detected due to reductions in countermovement jump impulse (14.7 ± 9.8 and 15.9 ± 15.5%), peak power (12.9 ± 8.5 and 11.9 ± 6.9%), peak velocity (8.6 ± 8.1 and 6.5 ± 6.0%), and peak force (7.0 ± 5.3 and 8.0 ± 6.1%) after the protocol (p < 0.001), for placebo and photobiomodulation therapy, respectively. Muscle damage was detected due to reductions in countermovement jump impulse (−6.1 ± 19.2% and −4.5 ± 9.2%, p < 0.05), increases in echo intensity (rectus femoris, 21.0 ± 11.9 and 20.8 ± 9.0%; and vastus lateralis, 22.4 ± 23.2%; and 16.7 ± 23.8%; p < 0.001), and quadriceps muscle soreness (3.6 ± 1.6 and 3.5 ± 1.7 a.u; p < 0.011), 48 h after the protocol, for placebo and photobiomodulation therapy, respectively. No differences were observed between photobiomodulation therapy and placebo at any time points for any variables (p > 0.05), indicating no positive effect favoring photobiomodulation therapy. In conclusion, our findings suggest no effect of photobiomodulation therapy applied before exercise to reduce lower limb muscle fatigue and damage during and following a stretch-shortening cycle protocol in judo athletes.

Neuromuscular and postural control in visually and nonvisually impaired judo athletes: case study

This study aimed to analyze neuromuscular and postural control in visually and nonvisually impaired judo athletes. Two judo athletes, one visually impaired and the other nonvisually impaired, participated in the study. The athletes presented similar demographic, anthropometric, and judo-technical characteristics. They performed maximal isometric handgrip strength (dominant and nondominant hand), vertical jumps (countermovement jump [CMJ] and squat jump [SJ]), and center of pressure assessment in three positions: neutral, anteroposterior, and judo combat base (Migi-shizentai). The main findings showed that the visually impaired athlete presented higher standing balance in the neutral and anteroposterior positions than non-visually impaired athlete (effect size [ES]>2.0). In the Migi-shizentai position, the disparity between both athletes was reduced, particularly in the displacement area (ES=0.52). The visually impaired athlete showed higher performance in the SJ but lesser performance in CMJ and handgrip strength tests than nonimpaired athlete (ES>2.0). We concluded that the postural stability was higher in the visually impaired athlete in the neutral and anteroposterior position, but similar to the nonvisually impaired athlete in Migi-shizentai position, possible due to the influence of judo practice. Moreover, the visually impaired athlete showed higher performance in the SJ than nonvisually impaired.

An Exploratory Double-Blind Study of Caffeine Effects on Performance and Perceived Exertion in Judo

This study analyzed the effects of caffeine ingestion during judo matches on judo athletes' match-derived performance and perceived exertion responses. We applied a double-blind randomized crossover (caffeine vs. placebo conditions) research design. Twelve male athletes performed three 5-minute matches separated by 15 minutes of passive rest. Immediately after each match, the athletes completed ratings of perceived exertion (RPEs), and one minute before beginning the second and third matches, they provided ratings of perceived recovery (RPRs). We filmed all matches for subsequent analysis of the athletes' technical skills. We found no interaction between condition and time of RPE, RPR, and match-derived technical variables, but number of attacks and RPR decreased over the matches, and RPE increased in both conditions. Three participants showed individual positive responses to caffeine ingestion for number of attacks. Attacks, efficiency, and effectiveness presented low sensitivity in both conditions, as only large changes could be identified. We conclude that caffeine ingestion did not provoke changes in either perceived exertion or match-derived performance. Match-derived technical variables were not sensitive for detecting small or medium effects of caffeine, but perceived exertion may detect at least medium effect after caffeine ingestion.

Validity of judo-specific tests to assess neuromuscular performance of judo athletes

Uchi-komi Fitness Test (UFT) is a specific judo test that evaluates physiological fitness of judo athletes in similar conditions to judo matches. Neuromuscular parameters obtained by generic and judo-specific tests would aid to get more information about its criterion validity. This study aimed to analyse the relationship between UFT and shoulder external (PT_EX) and internal (PT_INT) rotation torque, handgrip strength (HGS) and vertical jumps (VJs) performance. The relationship between UFT and Judogi grip strength test (JGST) was also investigated. Eighteen male judo athletes participated in this study. Athletes performed neuromuscular tests (VJ, PT_EX, PT_INT and HGS) and judo-specific tests (JGST and UFT). Pearson's correlation was used with the level set at p < 0.05. Significant correlation was found between UFT and all VJ variables (r = 0.50-0.72, p < 0.004), UFT a + b (two first series of UFT) and PT_EX (r = 0.49, p = 0.033), UFT and PT_INT (r = 0.47, p = 0.044). Also, UFT was correlated to JGST (r = 0.50-0.72, p < 0.044, respectively). We conclude that muscle power of lower limbs, PT_EX and PT_INT was related to UFT. Strength-endurance in the upper limbs (JGST) was also related to the UFT performance.

Effects of Mat Pilates on hip and knee isokinetic torque parameters in elderly women

This study aimed to analyze the effects of Mat Pilates on isokinetic torque of the lower limbs in elderly women. Fourteen elderly women (Age 62 ± 3 yr) participated in 12 weeks of Mat Pilates training (60-min sessions, 3 times per week). Repetitions increased every 4 weeks and the difficulty of exercises progressed from beginner to intermediate and advanced. Peak torque was assessed before (week -4 and week 0, considered as a control period) and after 6 and 12 weeks of a periodized Mat Pilates intervention. The results showed significant improvements (p < 0.05) in concentric and eccentric peak torque of knee flexors muscles, hip flexor and extensor muscles after 12 weeks. Mechanical work showed significant improvement (p < 0.05) for knee extensor muscles during eccentric contractions after week 12, for hip extensor muscles during concentric contractions week 12, and for flexor muscles during concentric and eccentric contractions after week 12. We conclude that the periodization of Mat Pilates induced significant improvements in multiple isokinetic torque parameters.

Is Vertical Jump Height an Indicator of Athletes' Power Output in Different Sport Modalities?

Kons, RL, Ache-Dias, J, Detanico, D, Barth, J, and Dal Pupo, J. Is vertical jump height an indicator of athletes' power output in different sports modalities? J Strength Cond Res 32(3): 708-715, 2018-This study aimed to identify whether the ratio standard is adequate for the scaling of peak power output (PPO) for body mass (BM) in athletes of different sports and to verify classification agreement for athletes involved in different sports using PPO scaled for BM and jump height (JH). One hundred and twenty-four male athletes divided into 3 different groups-combat sports, team sports, and runners-participated in this study. Participants performed the countermovement jump on a force plate. Peak power output and JH were calculated from the vertical ground reaction force. We found different allometric exponents for each modality, allowing the use of the ratio standard for team sports. For combat sports and runners, the ratio standard was not considered adequate, and therefore, a specific allometric exponent for these 2 groups was found. Significant correlations between adjusted PPO for BM (PPOADJ) and JH were found for all modalities, but it was higher for runners (r = 0.81) than team and combat sports (r = 0.63 and 0.65, respectively). Moderate agreement generated by the PPOADJ and JH was verified in team sports (k = 0.47) and running (k = 0.55) and fair agreement in combat sports (k = 0.29). We conclude that the ratio standard seems to be suitable only for team sports; for runners and combat sports, an allometric model seems adequate. The use of JH as an indicator of power output may be considered reasonable only for runners.

Prevalência de lesões em atletas de Brazilian jiu-jitsu: comparação entre diferentes níveis competitivos

This study aimed to identify types and sites of body injury, location of injury occurrence, and the mechanism and severity of injuries in novice and advanced Brazilian jiu-jitsu (BJJ) athletes. One hundred and eight BJJ athletes took part in this study separated in two groups: advanced (n = 53) and novice (n = 55). Athletes answered a questionnaire concerning regions of injury, locality of occurrence, injury severity and mechanism. Chi square test and a logistic regression analysis were used with the level of significance set at p < 0.05. The main results showed that shoulders and knees were the most injury location reported by novice and advanced athletes. Novice athletes demonstrated higher prevalence of injuries during training sessions (54.5%), whereas advanced athletes reported more injuries during competitions (66.1%). Significant associations between novice and advanced athletes were observed for major joints (p < 0.05). The odds ratio of having injury was 70-87% less for novice versus advanced athletes for the major joints cited. We concluded that BJJ athletes demonstrate high prevalence of injury mainly at knee and shoulder. While risk of injury appeared less in novice, the advanced demonstrated higher number of injuries during competitions as a consequence of injured joint keys. By contrast, novice athletes reported higher number of injuries associated with training sessions as a consequence of overuse.

Female Judo Athletes' Physical Test Performances Are Unrelated to Technical-Tactical Competition Skills

This study analyzed the relationship between generic and judo-specific physical test performances and technical-tactical competition performances among 19 female judo athletes. Participant data were gathered in two stages: (a) physical tests-countermovement jump (CMJ), handgrip strength, Special Judo Fitness Test and Judogi Grip Strength Test; and (b) match performances recorded for technical-tactical analysis. Pearson's linear correlation and multiple linear regression analysis showed no significant correlations between any technical-tactical parameter and judo-specific physical tests. However, the number of attacks during matches was significantly positively correlated with countermovement jump height (CMJ_JH; r = 0.69, p = .002), peak power output (CMJ_PPO; r = 0.53, p = .002), and peak velocity (CMJ_PV; r = 0.62, p = .001). Effective time during matches was significantly correlated with all CMJ parameters (except maximum force; r = 0.65-0.76, p ≤ .01) and with right hand grip strength ( r = 0.48, p = .037). Match effectiveness was correlated with CMJ_PPO ( r = -0.67, p = .001), mean power output (CMJ_MPO; r = -0.54, p = .017), and CMJ_PV ( r = -0.54, p = .004). The explained power of variance was low for all variables at 45-54%. We conclude that judo-specific performance tests do not seem to be related to female judo athletes' technical-tactical skills in official competition, though athletes with higher lower limb muscle power and higher handgrip strength showed higher time effectiveness during matches.

Effect of official judo matches on handgrip strength and perceptual responses

This study aimed to verify the effect of judo matches on handgrip strength and perceptual responses during an official tournament in medalists and nonmedalists. Thirty-four male judo athletes participated in an official judo tournament. Before the first match and immediately after each match, maximum isometric handgrip strength and rate of perceived exertion overall and in specific areas were assessed. Analysis of variance for repeated measures was used to compare variables before the first match and after each match, and t-test was used to compare medalists and nonmedalists with the level of significance set at 5%. Also, effect size (ES) analysis was used. The results showed decrease in handgrip strength in both hands from the third match (P<0.05). The rate of perceived exertion (RPE) increased from the first match and remained high over the subsequent matches (P<0.001). A very large effect for nonmedalist group (ES=3.44) and large effect for medalist group (ES=1.94) was found in the third match compared to prematch. Forearm and fingers were the body regions most cited by athletes in both groups. We concluded that an official judo competition induced significant drop in handgrip strength from the third match and increased the RPE from first match. Medalists seem to have better recovery after the third match compared to nonmedalists.

Olympic and Paralympic Games Rio 2016

The purpose of this study was to compare the athletes’ scores, penalties and efficiency between the Olympic and Paralympic Games Rio 2016, and identify which variable determined the winner of the matches. A total of 608 matches in the Olympic and Paralympic Games were analysed. Total relative scores (ippon, waza ari and yuko), penalties (shido per match) and efficiency were identified in the male and female categories, Olympic and Paralympic Games, and medallists and non-medallists. The main results showed that waza ari was higher in the Olympic Games (p=.05) than in the Paralympic Games (male team); ippon was higher in the Paralympic Games (p=.05) and shido was higher in the Olympic Games (p=.05) (female team). The male Olympic medallists were more efficient (p=.01), while the female Paralympic medallists were less penalised (p=.01). Ippon was the key variable that determined winning in both the Olympic and Paralympic matches (p&lt;.001). We concluded that the male Olympic judo athletes showed greater efficiency and scores than Paralympians, while the female team presented more scores and fewer penalties. Ippon was the key point that determined victory in most of the matches.

Methods and Magnitudes of Rapid Weight Loss in Judo Athletes Over Pre-Competition Periods

The study aimed to analyse the methods and magnitudes of rapid weight loss (RWL) in judo team members in distinct periods before the biggest state competition in Southern Brazil.

Twelve male judo athletes took part in the study. The data collection was performed in three periods: (1) three months before the biggest state competition, (2) one week before the competition, (3) the day prior to the event. Anthropometric assessment and the Rapid Weight Loss Questionnaire were performed. Student’s

The main results showed that the majority of athletes reduced 7.1 ± 6.8 kg and started to lose weight to compete 13–16 years earlier. Increasing exercises (91.7%) and restricting fluid intake (41.7%) were the most frequent methods of weight loss. The judo coach/sensei was the person who most influenced the RWL procedure (58.3%). The athletes reduced 5% of their body weight (p < 0.01), 2.4% of their body fat (

We conclude that RWL was a common and premature practice in the athletes in the study. The most common methods were increasing exercise volume and restricting fluid and food intake. The coach/sensei was the most influential person in this practice. The judo athletes presented decreases in body fat and fat-free mass during the period prior to the competition.