Development of tables for classifying judo athletes according to maximal isometric strength and muscular power, and comparisons between athletes at different competitive levels

Trunk, Mass Grasp, Knee, and Hip Muscle Performance in CrossFit Participants: Reference Values According to Participants' Sex and Limb Dominance

Background

CrossFit is characterized by a diverse range of exercises recruiting different muscles and requiring different muscle functions. A characterization of muscular performance parameters in this population is needed.

Purpose

To determine reference values for various aspects of muscular performance of muscles of the trunk, thigh, hip, and mass grasp in CrossFit participants. Also, this investigation aimed to compare the strength measures between male and female CrossFit participants, as well as between dominant and non-dominant limbs.

Design

Descriptive, Cross-sectional.

Setting

Laboratory.

Methods

Isometric strength of trunk extensors (TE) and mass grasp was measured with handheld and Jamar dynamometer respectively. An isokinetic dynamometer was used to assess the muscle performance of the knee flexors (KF) and extensors (KE) (at 60º/s and 300º/s), and hip flexors (HF), extensors (HE), and abductors (HA) (60º/s and 240º/s ). Reference values for torque, work, power, fatigue, flexor:extensor ratio for the knee (hamstring:quadriceps - H:Q) and hip (HF:HE) joints were calculated. The torque and work values were normalized by the body mass. Mixed multivariate and univariate analyses of variance and independent t-tests were used for statistical analyses to compare between sexes and limbs.

Results

Participants included 111 individuals (58 males and 53 females) with at least one year of experience in CrossFit. Normative data are provided for the outcome variables. Males had greater values of muscular performance parameters than females in most variables (p<0.05). Also, the dominant limb had greater mass grasp strength (p<0.002), greater KE power at 60º/s (p=0.015), lower H:Q ratio at 60º/s (p=0.021) and 300º/s (p=0.008), and lower KE fatigue (p=0.002).

Conclusion

This study provides reference values for the trunk extensors, mass grasp, knee, and hip muscle performance in male and female CrossFit practitioners. Their muscle performance profile was characterized by few inter-limb asymmetries, and males demonstrated greater muscular performance outcomes than females, even after normalization by body mass. These reference values can be used for comparisons in research and clinical settings.

Level of Evidence

3b.

Correlation of the Handgrip Strength and Body Composition Parameters in Young Judokas

Maximum isometric handgrip strength (MIHS) is a relevant parameter for judo performance and is related to health. Understanding the association between MIHS and MIHS relative (MIHSrel) and the absolute lean mass of the arm (LMarm) and the percentage of body fat (%BF) can provide important information for performance and health. The study aimed to investigate the correlation between MIHS and MIHSrel with the LMarm and the %BF of young judokas (sub-19, 15 males and 14 females). MIHS was measured using a multipurpose digital dynamometer with a load cell for computer. Body composition was measured by dual-energy X-ray absorptiometry (DXA). The correlation between MIHS, MIHSrel with LMarm and %BF was verified through Pearson's correlation, with a significance level of p < 0.05. Correlation between MIHSrel and %BF was very high only in female judokas for both arms (right, r = -0.76; left, r = -0.75). Correlations between LMarm and MIHS of the right and left arms ranged from very high to almost perfect for both sexes (r = 0.74 to 0.94). These results highlight the importance of strengthening the arms in young judokas, and controlling body fat for performance and health, especially in female judokas.

Effects of Supplementary Strength Program on Generic and Specific Physical Fitness in Cadet Judo Athletes

ABSTRACT

Branco, BHM, Marcondes, VA, de Paula Ramos, S, Badilla, PV, and Andreato, LV. Effects of supplementary strength program on generic and specific physical fitness in cadet judo athletes. J Strength Cond Res 36(10): 2816-2823, 2022-This study aimed to investigate the effects of a supplementary strength program on general and specific physical fitness in under-18 judo athletes. In total, 21 athletes were randomized into 2 groups: experimental group (EG: aged = 15.5 ± 1.2 years; body mass = 71.3 ± 10.6 kg; practice time = 5.1 ± 1.2 years) and control group (aged = 16.6 ± 0.5 years; body mass = 71.7 ± 11.0 kg; practice time = 5.6 ± 0.8 years). Athletes were submitted to anthropometry, generic physical fitness tests (countermovement jump, one-repetition maximum in bench-press, row, and half-squat machine), and specific field tests (isometric and dynamic judogi chin-up and Special Judo Fitness Test [SJFT]). All measurements were presented at baseline, and 8 athletes per group completed pre-training and post-training assessments. Both groups performed the same judo training routine, and the EG also performed 3/weekly/sessions of strength training for 8 weeks. All measurements were conducted during the competitive season. There were no differences in body mass, height, and body fat percentage after the training period (p > 0.05). Improvements were observed in maximal strength for bench press (26.6%), row (17.7%), half-squat machine (29%), dynamic judogi chin-up (33%), and the following SJFT responses: block A (16.7%), block B (11.3%), sum of 3 blocks (8.3%), heart rate after 1 minute (-7.0%), and index (-12.5%), representing performance improvement for the EG. It was concluded that 8 weeks of strength training was positive for general and specific performance. Finally, this strength program may help coaches to develop strength without changes in body mass.

Methodological considerations for assessing whole-body strength capacity through isometric dynamometry

The present study aimed to explore the possibility of comprehensively assessing whole-body muscle strength by testing as few muscle groups as possible, using a single testing method (isometric or isokinetic dynamometry) and a single variable (maximal force or rate of force development). Knee, hip, shoulder and elbow extensors and flexors were evaluated in males with high (n = 26) and low strength levels (n = 32). The principal component analysis revealed three factors that explained 62.5% of the total variance, while the main factors were loaded by the different testing methods and strength variables for the muscles acting on the knee (first component), hip (second component) and arm joints (third component). These results were confirmed by a three-way ANOVA which revealed a significant factor of group (P < 0.001) and the interaction test type × group (P = 0.002), but not of test type (P = 0.644), muscle group (P = 0.999), or their interactions (P > 0.205). The correlations of strength outcomes across the muscles ranged from trivial to very large (r range = -0.17, 0.84), being generally higher for the antagonistic muscles. Overall, a comprehensive assessment of whole-body muscle strength can be obtained using isometric dynamometry and maximal force, but it should consider at least one muscle group from the antagonistic pair.

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.

Monitoring Internal Training Load, Stress-Recovery Responses, and Immune-Endocrine Parameters in Brazilian Jiu-Jitsu Training

Campos, F, Molina Correa, JC, Canevari, VCM, Branco, BHM, Andreato, LV, and de Paula Ramos, S. Monitoring internal training load, stress-recovery responses, and immune-endocrine parameters in Brazilian jiu-jitsu training. J Strength Cond Res XX(X): 000-000, 2020-This study aimed to evaluate the relationship between training loads, stress, and immune-endocrine markers during a precompetitive period in Brazilian jiu-jitsu (BJJ) athletes. For this, 12 athletes were submitted to 1 physical and 1 technical-tactical training session per day, 5 days a week, for 7 weeks. The saliva sampling and physical tests (countermovement jump [CMJ] and squat jump [SJ]) were performed before starting the training period (pre) and at the fourth week (4-week) and eighth week (post). Session rating of perceived exertion (sRPE) and the Recovery-Stress Questionnaire-Sport (RESTQ) were applied, and the training load was calculated weekly. Repeated-measures analysis of variance and the Friedman test were used, with significance levels set at p < 0.05. Increased training loads were recorded by the sRPE method in technical-tactical training sessions (p < 0.05). Higher physical loads were reported by athletes during weeks 1-4, contributing to overall higher training load, monotony, and strain during this period (p < 0.05). Increased perception of stress, by the RESTQ, and cortisol were detected, whereas decreased salivary testosterone and salivary immunoglobulin A were observed at 4 weeks (p < 0.05). No significant differences were detected in CMJ and SJ tests, suggesting that training neither elicited significant fatigue and underperformance nor improved strength performance. However, decreasing physical training loads appeared to reduce symptoms of stress and improved recovery, favoring immune recovery and anabolic balance. Thus, the sRPE seems to be a reliable and simple method to monitor training loads in BJJ athletes because variation in values was related to the RESTQ and physiological responses to training loads.

Somatotypes and hand-grip strength analysis of elite cadet sambo athletes

The objectives of this research were to establish somatotype and hand-grip strength between elite cadet male and female sambo athletes divided by weight categories.A total of 97 elite cadet sambo athletes, participants of the World Cadets Sambo Championships 2018 participated in the study. Male and female sambo athletes were divided by official weight categories. Anthropometrical variables were taken in order to calculate somatotypes and hand-grip strength. A one-way analysis of variance and Tukey's post hoc tests were used to compare group differences by weight categories.Results of this study provide the first description of somatotype and hand-grip strength of elite male and female cadet sambo athletes in relation to weight category. A typical somatotype in male sambo athletes was endomorphic mesomorphs with a predominance of musculoskeletal tissue, while female athletes differed concerning weight category. Overall, an increase in handgrip strength across weight categories was noted. Hand-grip strength increases linearly from the lightest to the heaviest weight category except in -66 and -84 kg in male athletes. Differences in handgrip strength of female athletes were detected between the lightest group and last six groups in all three variables in favor of last six as well as -44 and kg -48 kg compared with the heaviest.To the best of our knowledge, this study provides the first normative data of somatotype and hand-grip strength analyses in relation to age, gender, and weight categories of cadet sambo athletes. The anthropometric profile of sambo athletes changed according to their weight category. Mesomorphy was the most dominant somatotype component in male athletes, while female had three different types of somatotype component in relation to weight category. In conclusion, we found differences in hand-grip strength related to weight category, which can be linked to the muscle mass of athletes. Future studies should focus on somatotype and strength handgrip values of international compared to national level sambo athletes.

Effects of the Order of Physical Exercises on Body Composition, Physical Fitness, and Cardiometabolic Risk in Adolescents Participating in an Interdisciplinary Program Focusing on the Treatment of Obesity

The main objective of this study was to investigate the effects of the order of physical exercises on body composition, physical fitness, and cardiometabolic risk in adolescents participating in an interdisciplinary program focusing on the treatment of obesity. The final 12-week analyses involved 33 female adolescents who were split into two groups of concurrent training (CT): resistance plus aerobic training and aerobic plus resistance training, with equalization performed in all physical exercises. The only difference between the two groups was the order in which the exercises were performed. The results showed reductions in fat mass, body fat, and waist circumference, as well as increases in musculoskeletal mass and resting metabolic rate (p < 0.05) following the multiprofessional intervention period. However, no significant differences were observed in regard to body mass, body mass index, neck circumference, or arm circumference (p > 0.05). Maximal isometric strength and maximal oxygen consumption showed significant increases after the intervention period (p < 0.05). There were reductions in insulin, HOMA-IR, total cholesterol, triglycerides, and low-density lipoproteins (p < 0.05), and an interaction within the resistance plus aerobic training group showed lower values for triglycerides when compared to itself (p = 0.002). No difference was found in fasting glycemia for either group (p > 0.05). It is worth noting that the equalization training variables presented no differences between the two groups (p > 0.05). Based on these results, both CT methods were found to be effective in promoting health parameters in overweight and obese female adolescents, and triglyceride values decreased more in the resistance plus aerobic group. Future studies with larger samples and feeding control should be conducted to confirm or refute our findings.

Maximal isometric handgrip strength: comparison between weight categories and classificatory table for adult judo athletes

The aims of this study were to compare the maximal isometric handgrip strength of judo athletes from different weight categories and to create a classificatory table for this test. A total of 406 athletes had their maximal isometric handgrip strength measured, following standardized recommendations. Absolute and relative values were calculated for each hand and for the sum of both hands. Weight categories were compared through a one-way analysis of variance, followed by Tukey test. The effect size was determined by partial eta squared, and the relationship between variables was determined using Pearson correlation coefficient. There was a large effect of weight category in absolute handgrip strength for each hand and for the sum of both hands, with lower values for the lighter categories. Conversely, when the relative strength was considered higher values were found for the lighter categories (P<0.001). Very large and significant positive correlations (P<0.001) were found between right and left for absolute (r=0.886) and relative (r=0.883) handgrip values. Overall, there was an increase in absolute and a decrease in relative handgrip strength across weight categories. These differences found in grip strength in weight categories are probably linked to differences in muscle mass between them. There was a high correlation between each hand for absolute and relative values, which suggests that assessing only one hand may be enough, and therefore a faster way of evaluation. Finally, the normative classificatory table created may serve as a reference for different purposes.