Intra-unit reliability and movement variability of submission grappling external load as measured by torso mounted accelerometery.

Submission grappling consists of skills and movements used in combat sports to physically control opponents whilst trying to apply choke holds and joint locks. There is currently no accepted method of monitoring external load in grappling-based sports due to the absence of key variables such as distance, velocity or time. The primary aim of this study was to determine whether PlayerLoad is a reliable variable for measuring external load of submission grappling movements, with a secondary aim of determining the between repetition variance of submission grappling movements. 7 experienced submission grapplers were recruited. Each wore a torso mounted Catapult® Optimeye S5 microelectromechanical systems (MEMS) device and completed 5 repetitions of each of the following: 4 submission techniques; 5 transition techniques; 2 guard pass techniques; 2 takedown techniques. Accumulated PlayerLoad (PLdACC) was recorded as a marker of absolute load, with accumulated PlayerLoad per minute (PLdACC∙min-1) representing relative load. Reliability of each was assessed using intraclass correlation coefficient (ICC(3,1)) (≥ 0.70). Between repetition movement variation was assessed via coefficient of variation with 95% confidence intervals (CV, 95%CI) (acceptable ≤ 15%, good ≤ 10%). PLdACC ICC(3,1) range = 0.78-0.98, with CV range = 9-22%. PLdACC∙min-1 ICC(3,1) range = 0.83-0.98, with CV range = 11-19%. Though several variables displayed CV > 15%, all had 95%CI lower boundaries ≤ 15%. Whilst PlayerLoad was found to be a reliable measure for submission grappling, relatively high CVs across most techniques examined suggest PlayerLoad may not be appropriate for measuring changes in external load for individual movements in submission grappling. However, it may prove a useful tool for monitoring the external load of full, grappling-based, training sessions within an individual.

Homosexual Behavior Between Male Spider Monkeys (Ateles geoffroyi).

Homosexual behavior is defined as genital contact or genital manipulation between same-sex individuals. In nonhuman primates, it may regulate social relationships by serving as a means of reconciliation, tension alleviation, or alliance formation. Grappling is a rare and complex behavior, which most frequently occurs between same-sex individuals of the genus Ateles and can include mutual manipulation of the genitalia. Here we report three cases of penile-anal intromission during grappling between wild male spider monkeys living in the natural protected area of Otoch Ma'ax Yetel Kooh, Mexico. In all the observed cases, the same adult male was the actor. To our knowledge, this is the first report of penile-anal intromission between males in any New World primate species.

Cadet and Junior Performance Is Associated With Senior's World Championship and Olympics Achievement in Judo.

Purpose: We determined whether cadet and junior Judo World Championship participation and medal achievement would predict senior performance at World Championship (WC) and Olympic Games (OG). Methods: We analyzed retrospectively a total of 7780 athletes who competed at the OG and WC in the cadet, junior, and senior between 2009 and 2021. Results: There was an increase in the probability of winning a medal in the senior category (WC and OG, and only WC) ranged from 4.3 to 4.5 for medal-winning cadets compared to non-medalists and this probability remained around 3.3-3.8 for medalists in the male and 5.3-5.4 for the female medalists in cadet WC. Moreover, the chance of winning a medal in the senior category (WC and OG) was 8.1-8.5 times greater for medalists when compared to non-medalists in the junior WC. In turn, the probability of winning a medal in the senior (WC) was 1.5-1.7 times greater for athletes who did not compete in the junior WC. In the OG, the probability of winning a medal was 3.5 greater times for medalists when compared to non-medalists at cadet and junior WC. Conclusion: Thus, being a cadet or junior WC medalist increases the probability of winning a senior WC or an Olympic medal.

Same-sex sexual behavior in brown-headed spider monkeys (Ateles fusciceps fusciceps) during grappling between two subadult males.

Sexual behavior in animals fulfills reproductive and social functions, extending beyond the traditional focus on reproduction. Same-sex sexual behavior, defined as genital contact or manipulation between individuals of the same sex, occurs in various primate species. In spider monkeys, grappling, a behavior involving prolonged mutual embraces, face greeting, tail intertwining, and genital manipulation, occurs primarily between males. Here, we report a novel incidence of same-sex sexual behavior and grappling between two subadult male brown-headed spider monkeys (Ateles fusciceps fusciceps). Our observation contributes to the understanding of the social functions of sexual behavior and to the broader appreciation of primate sexuality.

Experience, Training Preferences, and Fighting Style Are Differentially Related to Measures of Body Composition, Strength, and Power in Male Brazilian Jiu Jitsu Athletes-A Pilot Study.

To examine relationships between Brazilian Jiu Jitsu (BJJ) descriptors (belt rank, experience, gi preference, and fighting style), resistance training (RT) experience, and measures of body composition, strength (maximal handgrip, 3-5-repetition maximum [RM] in barbell glute bridge [GB], prone bench row [PBR], and bench press [BP]), and velocity (GB, PBR, and BP at 7 kg and 30−60% 1-RM), 13 experienced (4.3 ± 3.4 years) BJJ athletes were recruited for this cross-sectional, pilot study. Significant (p < 0.05) Kendall's tau and Bayesian relationships were seen between belt rank and body fat percentage (τ = −0.53, BF10 = 6.5), BJJ experience and body fat percentage (τ = −0.44 to −0.66, BF10 = 2.6−30.8) and GB velocity (τ = −0.45 to −0.46, BF10 = 2.8−3.1), RT experience and strength (τ = 0.44 to 0.73, BF10 = 2.6−75.1) and velocity (τ = −0.44 to 0.47, BF10 = 2.6−3.3), gi preference-training and relative PBR strength (τ = 0.70, BF10 = 51.9), gi preference-competition and height and lean mass (τ = −0.57 to 0.67, BF10 = 5.3−12.4) and BP velocity (τ = −0.52 to 0.67, BF10 = 3.5−14.0). The relevance of body composition and performance measures to sport-specific training and research interpretation are differentially affected by a BJJ athlete's experience (BJJ, belt rank, RT), gi preferences, and fighting style.

Functional results of modified Mason-Allen suture versus horizontal mattress suture in the arthroscopic Broström-Gould procedure for chronic ankle instability.

BACKGROUND: The arthroscopic Broström-Gould procedure (ABG) gained particular attention among clinicians and researchers due to its high rate of satisfactory results. There is a lack of evidence regarding the differences in clinical outcomes for the various suture techniques. The purpose of this study was to compare the differences in clinical effect in patients treated with one-anchor modified Mason-Allen suture or two-anchor horizontal mattress suture for chronic ankle instability (CAI). METHODS: This retrospective cohort study examined CAI patients who underwent either one-anchor modified Mason-Allen suture or two-anchor horizontal mattress suture ABG between January 2018 and January 2020. Patients were divided into two groups based on the suture knot type used and the associated number of anchors. The operative time, surgical cost, Visual Analog Scale (VAS), American Orthopedic Foot & Ankle Society (AOFAS) Score, Karlsson Ankle Functional Score (KAFS), the rate of return to sports, complications, and measured biomechanical strength using standardized equipment were compared between groups. RESULTS: Sixty-four CAI patients were included (one-anchor modified Mason-Allen suture group n = 30, two-anchor horizontal mattress suture group n = 34). Compared to the two-anchor horizontal mattress suture group, the one-anchor modified Mason-Allen suture group had significantly shorter operative time (p < .001) and lower surgical cost (p < .001). There were no postoperative complications in the two groups, and no significant differences in the VAS, AOFAS, KAFS, and rate of return to sports in postoperative follow-up between the two groups at 1 and 2 years after surgery. There was no statistically significant difference in biomechanical strength anterior drawer test displacement (p > .05) between the one-anchor modified Mason-Allen suture and two-anchor horizontal mattress suture at 2 years after surgery. CONCLUSION: ABG using a one-anchor modified Mason-Allen suture showed comparable clinical results to a two-anchor horizontal mattress suture in the treatment of CAI at intermediate-term follow-up time. However, one-anchor modified Mason-Allen suture may be a faster, simpler, cost-effective substitute technology. LEVEL OF EVIDENCE: Level III, comparative study.

Caffeine ingestion increases the upper-body intermittent dynamic strength endurance performance of combat sports athletes.

The aim of this study was to investigate the effects of caffeine ingestion on upper-body intermittent strength endurance performance of combat sports athletes. Using a double-blind and placebo-controlled crossover design, ten experienced judo and jiu-jitsu athletes performed an upper-body intermittent strength endurance protocol (four set of judogi dynamic strength endurance test, interspersed by 3-min recovery intervals) 60 min after ingesting either caffeine (5 mg·kg-1) or placebo. Compared with placebo condition, caffeine ingestion significantly increased the total number of repetitions (+ 7%, P = 0.04; d = 0.44) and the maximal isometric handgrip strength (+ 5%, P = 0.03, ηp2 = 0.41). Rating of perceived exertion, heart rate and blood lactate concentration increased linearly throughout the test (P < 0.05), but without significant differences between caffeine and placebo conditions (P > 0.05). Caffeine ingestion improved the upper-body intermittent strength endurance performance and maximal isometric strength of combat sports athletes. This suggests that caffeine could help to maintain high levels of maximal handgrip and endurance strength in upper limbs, especially forearm muscles, which are responsible for maintaining the grip on the opponent's judogi.Highlights Caffeine ingestion improved upper-body intermittent strength endurance of grappling athletes.Caffeine ingestion increased maximal isometric handgrip strength of grappling athletes.Heart rate, lactate concentration or rating of perceived exertion were not affected by caffeine ingestion.Our findings suggest that caffeine could help to maintain high levels of maximal handgrip and endurance strength in upper limbs, especially forearm muscles, which are responsible for maintaining the grip on the opponent's judogi.

Analysis of Successful Behaviors Leading to Groundwork Scoring Skills in Elite Judo Athletes.

The present study aimed (1) to propose an approach of observational analysis of the preceding standing judo (tachi-waza (TW)) context to a groundwork (ne-waza (NW)) grappling score (NWGS), and (2) to analyze the outcomes of applying such a model in high-level judoists. We conducted an observational analysis of 176 NW scoring actions of 794 combats observed in Baku's World Judo Championships of 2018. Women scored more NWGS, performing more corporal controls but less segmental controls compared with the men. Moreover, NWGS were scored predominately during the second and third minutes of combat, independently of the sex or the weight category. Most NWGS occurred after an asymmetrical lateral structure, without showing associations with a particular type of NWGS. The movement structure of the attacking action during TW leading to an NWGS was predominantly techniques without turn, followed closely by techniques with turn, and barely performed after supine position techniques. Data showed that NWGS occurred more frequently after a failed TW attack (68.6%) than after a scored TW attack (31.4%). The TW attacker achieved NWGS with a higher frequency (62%) than the TW defender (38%), who mainly took advantage of a failed TW attack (98.5% vs. 1.5%, after failed vs. scored TW, respectively). The grip configurations most frequently employed during TW were dorsal-sleeve and flap-sleeve; overall, frontal grips were predominant over dorsal grips. However, no specific TW grip was related to success or grip progression before an NWGS. Our results will help judo coaches understand the influence of these factors on judo performance and optimize the planning and execution of technical-tactical content.

Rapid Weight Loss Practices in Grapplers Competing in Combat Sports.

BACKGROUND: Grappling is a wrestling style that combines different techniques such as freestyle wrestling, jiu-jitsu, judo, sambo, and others. As with other combat sports, it requires categorizing the athletes in weight classes, which leads to the use of certain methods to lose body weight in a short amount of time which poses a serious threat to athletes' health and wellbeing. Therefore, the objective of this study was to investigate the most widespread rapid weight loss (RWL) methods and sources of influence used by grappling athletes. METHODS: A total of 145 athletes took part in the study by voluntarily filling out a questionnaire regarding their weight loss techniques and methods. They were divided into two groups, male (27.7 ± 5.2 years, 1.76 ± 0.13 m, and 82.1 ± 20 kg) and female (27.33 ± 6.3 years, 1.65 ± 0.08 m, and 64.3 ± 10.4 kg), for further statistical analysis. After calculating descriptive statistics for all the variables, a t-test was conducted for gender differences in weight loss and weight regain, and a chi-square test measured the diversity in techniques and source of influence. RESULTS: Out of 145 participants, 120 athletes (85.2%) reported engaging in rapid weight loss prior to weigh-in. Coaches (52.4 and 59%) and teammates (42.6 and 22.1%) seemed to be the most influential on their rapid weight-loss strategies, whereas physicians (17.1 and 17.9%) and parents (23.2 and 23.1%) were the least influential. A statistical difference between men and women (p = 0.05) was found when teammates were a source of influence (42.6 and 21.1%, respectively). Regarding the methods used, both groups practiced gradual dieting (85.4 and 79.5%) as the most prevalent, followed by increased exercise (79 and 66.6%) and sauna (78.7 and 66.6%). Moreover, men trained in plastic suits significantly more often than women (67.1 vs. 41%, p = 0.01). CONCLUSION: Rapid weight loss is detrimental to athletes' health and wellbeing. Hence, it is crucial to find and implement methods that will control and ultimately limit its use in combat sports. Physicians and nutritionists need to be closely linked with the staff, collaborate and supervise the weight cutting.

Injury Patterns, Risk Factors, and Return to Sport in Brazilian Jiu Jitsu: A Cross-sectional Survey of 1140 Athletes.

BACKGROUND: Brazilian jiu jitsu (BJJ) is a growing martial art that focuses on grappling techniques. PURPOSE: To quantify the 3-year incidence of BJJ-related injuries and detect common injury patterns as well as risk factors among those practicing BJJ. It was hypothesized that there would be a high incidence of injuries, they would be caused by submissions in sparring situations, and they would occur predominantly at the extremities. STUDY DESIGN: Descriptive epidemiology study. METHODS: Active BJJ athletes were invited to take an English-language online survey developed by orthopaedic surgeons together with BJJ athletes and a sports scientist. Data were recorded regarding athlete demographics, sporting activity level, injuries within the past 3 years that caused at least a 2-week time loss, injury mechanisms, and return to sport. RESULTS: Overall, 1140 responses were received from 62 different countries; 88.9% of all athletes were male, and 63.9% were regular competitors. Within the investigated cohort, 1052 injuries were recorded in 784 athletes, for an injury incidence of 308 per 1000 athletes per year. The lower extremity (45.7%) and upper extremity (30.2%) were predominant sites of injury, with injuries to the knee (27.1%) being the most common. The most frequent knee injuries were meniscal injuries (n = 65), anterior cruciate ligament (ACL) tears (n = 36), and medial collateral ligament injuries (n = 36). ACL tears were especially associated with long time frames for return to sport. Most injuries occurred during sparring (77.6%) and were caused by submissions (29.7%) and takedowns (26.4%). Competing regularly (P = .003), older age (P < .001), and higher belt rank (P = .003) were significant risk factors for injury. CONCLUSION: Injury incidence was high among BJJ athletes surveyed, with 2 out of 3 athletes reporting at least 1 injury within a 3-year period that caused a 2-week absence from training. Most injuries occurred during sparring, and we believe that a high potential for injury reduction lies in drawing awareness to common injury patterns and sites in athletes.

S-layers at second glance? Altiarchaeal grappling hooks (hami) resemble archaeal S-layer proteins in structure and sequence.

The uncultivated "Candidatus Altiarchaeum hamiconexum" (formerly known as SM1 Euryarchaeon) carries highly specialized nano-grappling hooks ("hami") on its cell surface. Until now little is known about the major protein forming these structured fibrous cell surface appendages, the genes involved or membrane anchoring of these filaments. These aspects were analyzed in depth in this study using environmental transcriptomics combined with imaging methods. Since a laboratory culture of this archaeon is not yet available, natural biofilm samples with high Ca. A. hamiconexum abundance were used for the entire analyses. The filamentous surface appendages spanned both membranes of the cell, which are composed of glycosyl-archaeol. The hami consisted of multiple copies of the same protein, the corresponding gene of which was identified via metagenome-mapped transcriptome analysis. The hamus subunit proteins, which are likely to self-assemble due to their predicted beta sheet topology, revealed no similiarity to known microbial flagella-, archaella-, fimbriae- or pili-proteins, but a high similarity to known S-layer proteins of the archaeal domain at their N-terminal region (44-47% identity). Our results provide new insights into the structure of the unique hami and their major protein and indicate their divergent evolution with S-layer proteins.