Effects of 12 weeks of functional training vs. Muay Thai on cardiac autonomic modulation and hemodynamic parameters in older adults: a randomized clinical trial.

BACKGROUND: The elevated blood pressure (BP) and lower cardiac autonomic modulation (CAM) are associated with higher morbidity mortality risk among older adults. Although exercise is an important intervention for cardiovascular promotion, it is unclear whether combat sports training could benefit cardiovascular outcomes as much as autonomic in this population. This study compared the effects of 12 weeks of Muay Thai (MT) training against functional training (FT) on CAM and hemodynamic parameters in older adults. METHODS: The sample consisted of 50 older adults (41 women; 66.0 ± 5.3 years old), who were equaly randomized into FT (n = 25) and MT (n = 25) intervention groups. CAM was measured by 30-min rest heart rate variability. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and resting heart rate (RHR) were measured using an automatic oscillometric device. Pulse pressure (PP) and the double product (DP) were also calculated. The interventions were carried out three times a week, with 60-min length per session, during 12 consecutive weeks. The intensity of the interventions was measured using the subjective perception of exertion scale and by accelerometer. Two-factor repeated measures analysis of covariance was used for groups comparison, considering intervention group and body mass as factors. The 95% confidence interval of the difference (95%CIdif) was also calculated and the effect size was measured using partial eta squared (η2p). RESULTS: CAM indices did not show significant changes across moments and intervention groups. In hemodynamic parameters, only in DBP was there an effect of the moment (F1,39 = 8.206; P = 0.007; η2p = 0.174, large) and interaction effect between group*moment (F1,39 = 7.950; P = 0.008; η2p = 0.169, large). Specifically, the MT group at the post-training moment showed lower DBP (P = 0.010; 95%CIdif = -13.3; -1.89) in relation to the FT group. Furthermore, the MT group showed a decrease in DBP during training (P = 0.002; 95%CIdif = -10.3; -2.6). Also, an increase in training intensity was also found over the 12 weeks in FT, with no difference between the groups. CONCLUSION: After 12 weeks of MT practice there was a reduction in DBP compared to FT in older adults. TRIAL REGISTRATION: NCT03919968 Registration date: 01/02/2019.

Acute and Chronic Weight-Making Practice in Professional Mixed Martial Arts Athletes: An Analysis of 33 Athletes Across 80 Fights.

Mixed martial arts' popularity has increased in recent years, alongside descriptive research and evidence-based performance recommendations. Guidelines for (both chronic and acute) weight making exist; however, how these translate in real-life scenarios and detailed investigations on practices in larger groups deserve attention. The present study examined the body mass (BM) and composition of 33 professional mixed martial arts athletes preparing for 80 fights. Athletes were supported by on-site dietitians, who encouraged evidence-based practices. Fasted BM was measured throughout the last ∼10 days before all bouts (acute weight management phase). A subset of athletes had body composition assessed before and after the chronic weight loss phase for 40 fights. Most athletes engaged in chronic BM loss, and all engaged in acute weight loss. Many lost fat-free mass (FFM) during the chronic phase, with rates of BM loss <0.5% best preserving FFM. Regardless of losses, the present athletes possessed greater FFM than other combat sport athletes and engaged in greater acute weight loss. Dehydration in the 24-48 hr before the weigh-in was not reflective of weight regain after the weigh-in, rather BM 7-10 days before the weigh-in was most reflective. These findings suggest that many mixed martial arts athletes could increase FFM at the time of competition by maintaining leaner physiques outside of competition and/or allowing increased time to reduce BM chronically. Acutely, athletes can utilize evidence-based protocols, eliminating carbohydrates, fiber, sodium, and finally fluid in a staged approach, before the weigh-in, reducing the amount of sweating required, thus theoretically better protecting health and preserving performance.

Boxing Punch Detection with Single Static Camera.

Computer vision in sports analytics is gaining in popularity. Monitoring players' performance using cameras is more flexible and does not interfere with player equipment compared to systems using sensors. This provides a wide set of opportunities for computer vision systems that help coaches, reporters, and audiences. This paper provides an introduction to the problem of measuring boxers' performance, with a comprehensive survey of approaches in current science. The main goal of the paper is to provide a system to automatically detect punches in Olympic boxing using a single static camera. The authors use Euclidean distance to measure the distance between boxers and convolutional neural networks to classify footage frames. In order to improve classification performance, we provide and test three approaches to manipulating the images prior to fitting the classifier. The proposed solution achieves 95% balanced accuracy, 49% F1 score for frames with punches, and 97% for frames without punches. Finally, we present a working system for analyses of a boxing scene that marks boxers and labelled frames with detected clashes and punches.

The effects of training type and area size variations on the physiological and session rating of perceived exertion responses during male judo matches.

Modified exercise prescription in judo is commonly used to activate the energy systems in different magnitudes. In order to study the physiological and rating of perceived exertion (RPE) responses according to area sizes (i.e., 4 m × 4 m, 6 m × 6 m and 8 m × 8 m) and training mode variations (i.e., groundwork, ne-waza; standing combat only, tachi-waza; and free combat, free randori), eighteen male judo athletes (age: 22.6 ± 1.8 years) were randomly assigned, on separate days, to 9 experimental conditions (3 area sizes × 3 training modes) with each condition lasting 4 min. Delta lactate [La] was calculated based on the blood lactate values measured before and after every condition. Heart rate (HR) was measured during and after each bout and RPE recorded at the end of each combat. The results showed that mean and peak HR, percentage of maximum HR (% HRmax), delta [La] values and RPE scores were lower in 4 m × 4 m compared to 6 m × 6 m and 8 m × 8 m, and in groundwork training mode compared to standing combat and free randori (all p < 0.001). Furthermore, the 6 m × 6 m condition induced lower delta [La] values than 8 m × 8 m (p < 0.001) and free randori resulted in higher RPE scores than standing combat (p = 0.001). In conclusion, different training variables can be easily manipulated in a variety of different ways to specifically activate the energetic systems. Focusing on groundwork, the 6 m × 6 m area size was found to be the most suitable condition to induce a higher cardiovascular response, while the standing combat and free randori in 6 m × 6 m resulted in increased glycolytic activation compared to the groundwork condition.

A Comparative Analysis of High-Intensity Technique-Specific Intervals and Short Sprint Interval Training in Taekwondo Athletes: Effects on Cardiorespiratory Fitness and Anaerobic Power.

Technique-specific high-intensity interval training (HIITTS) has been proven to be an effective method to enhance the sport-specific bio-motor abilities of taekwondo athletes. However, studies regarding its effects on comprehensive measures of cardiorespiratory fitness are limited. Furthermore, there is a lack of clarity regarding the extent of individual adaptations to this method compared to HIIT in the form of repeated sprints (HIITRS). This study compared the individual adaptations to HIITRS and HIITTS on cardiorespiratory fitness and anaerobic power in trained taekwondo athletes (age = 19.8 ± 1.3 years; body mass = 75.4 ± 9.1 kg; height = 1.73 ± 0.0 .m). All participants completed three sessions per week of a 60-minute regular taekwondo training. Following the 60-minute training, participants completed 3 sets of 10 × 4 s all-out HIITRS or same sets of repeated kicks with both legs (HIITTS) over a 6-week training period. In both groups, rest intervals were set at 15 seconds between efforts and one minute between sets. Before and after the training period, participants underwent a series of lab- and field-based tests to evaluate cardiorespiratory fitness and bio-motor abilities. Both interventions resulted in significant improvements in maximum oxygen uptake (V̇O2max), O2 pulse (V̇O2/HR), first ventilatory threshold (VT1), second ventilatory threshold (VT2), cardiac output (Q̇max), stroke volume (SV), peak power output (PPO), average power output (APO), squat jump (SJ), and countermovement jump (CMJ). However, linear speed (20-m speed time) and taekwondo-specific agility test (TSAT) only responded to HIITRS. HIITRS resulted in greater changes in V̇O2max, V̇O2/HR, VT2, and Q̇max, and higher percentage of responders in measured parameters than HIITTS. In addition, HIITRS elicited lower inter-individual variability (CV) in percent changes from pre- to post-training in all measured variables. These results suggest that incorporating 3 sessions per week of HIITRS into regular taekwondo training results in significantly greater and more homogenized adaptations in cardiorespiratory fitness and bio-motor abilities than HIITTS among trained taekwondo athletes.

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.

Acute effects of concurrent muscle power and sport-specific endurance exercises on markers of immunological stress response and measures of muscular fitness in highly trained youth male athletes.

PURPOSE: To examine the acute effects of concurrent muscle power and sport-specific endurance exercises order on immunological stress responses, muscular-fitness, and rating-of-perceived-exertion (RPE) in highly trained youth male judo athletes. METHODS: Twenty male participants randomly performed two concurrent training (CT) sessions; power-endurance and endurance-power. Measures of immune response (e.g., white blood cells), muscular-fitness (i.e., counter-movement-jump [CMJ]), RPE, blood-lactate, and -glucose were taken at different time-point (i.e., pre, mid, post, and post6h). RESULTS: There were significant time*order interactions for white blood cells, lymphocytes, granulocytes, granulocyte-lymphocyte-ratio, and systemic-inflammation-index. Power-endurance resulted in significantly larger pre-to-post increases in white blood cells and lymphocytes while endurance-power resulted in significantly larger pre-to-post increases in the granulocyte-lymphocyte-ratio and systemic-inflammation-index. Likewise, significantly larger pre-to-post6h white blood cells and granulocytes increases were observed following power-endurance compared to endurance-power. Moreover, there was a significant time*order interaction for blood-glucose and -lactate. Following endurance-power, blood-lactate and -glucose increased from pre-to-mid but not from pre-to-post. Meanwhile, in power-endurance blood-lactate and -glucose increased from pre-to-post but not from pre-to-mid. A significant time*order interaction was observed for CMJ-force with larger pre-to-post decreases in endurance-power compared to power-endurance. Further, CMJ-power showed larger pre-to-mid performance decreases following power-endurance, compared to endurance-power. Regarding RPE, significant time*order interactions were noted with larger pre-to-mid values following endurance-power and larger pre-to-post values following power-endurance. CONCLUSION: CT induced acute and delayed order-dependent immune cell count alterations in highly trained youth male judo athletes. In general, power-endurance induced higher acute and delayed immunological stress responses compared to endurance-power. CMJ-force and RPE fluctuated during both CT sessions but went back to baseline 6 h post-exercise.

Karatekas educated on injury prevention and supported by fitness coaches are more likely to practise injury prevention.

To determine the current perceptions and practices of top-level karate athletes concerning risk factors and injury prevention programme (IPP) implementation in training and competition. Out of 90 eligible countries (933 athletes) participating in the karate World Senior Championships (WSC) in Madrid 2018, 50 countries (55.6%) represented by 137 athletes (14.7%; 52 females and 85 males) responded to a structured questionnaire. Of the athletes responding, 45% reported that their national team did not conduct any measures to reduce injury risk (43% among females and 47% among males; p = 0.68). Kumite athletes (51%) were more likely to practise injury prevention compared to kata athletes (25%; p = 0.016). Of the respondents, 69%, 60%, 60% and 34% reported having no team doctor, fitness coach, massage therapist and physiotherapist, respectively. A greater proportion of athletes who had access to a fitness coach (part-time or full-time) engaged in injury prevention strategies (67% and 51%, respectively) than those who did not (35%; p = 0.031). Athletes who had received previous advice about injury prevention were more likely to practise injury prevention (58%) compared to the rest (21%; p < 0.001). The current study revealed that: i) almost half of the karatekas already benefited from an injury prevention programme, ii) injury prevention programmes were practised more frequently when there was a fitness coach among their coaching staff, iii) karatekas who had received education about injury prevention were more likely to practise injury prevention programmes.

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.

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.

External Apical Root Resorption in Orthodontic Patients Who Practice Combat Sports: A Case-Control Observational Pilot Study.

Orthodontic treatment could lead to undesirable effects such as external apical root resorption (EARR). Moreover, trauma to both the face and teeth can predispose to EARR. On the other hand, the practice of combat sports results in increased maxillofacial injuries. Consequently, our objective was to determine if there is a statistically significant difference in the EARR of the patients undergoing fixed orthodontic treatment who practice combat sports and controls. Our null hypothesis was that there is no difference in the EARR between patients undergoing orthodontic treatment who practice combat sports and the patients under the same treatment that do not practice combat sports. An observational, descriptive, and prospective case-control pilot study was designed. The exposed group consisted of patients that practice combat sports. Whereas the control group was conformed of patients that do not practice combat sports without a previous history of facial trauma and without face trauma during the orthodontic treatment. EARR of the maxillary and mandibular anterior teeth was measured using cone-beam computed tomography (CBCT). The CBCT scans were obtained from all patients prior to the beginning of the orthodontic treatment and 1 year later. At the end of the follow-up for the maxillary right central and lateral incisors of the exposed group, the EARR was significantly higher than the homologous teeth of the control group (p < 0.05). As a consequence, the patients treated orthodontically who practice combat sports could be more susceptible to EARR.

Effects of intensified training and tapering periods using different exercise modalities on judo-specific physical test performances.

This study investigated the effects of intensified training and tapering periods using different exercise modalities on judo athletes' physical fitness. Fifty-nine adolescent male and female judo athletes (age 15 ± 1 years) were randomly assigned to one of three experimental groups or one control group (CG). Experimental groups (kumi-kata [KG], uchi-komi [UG] and running [RG]) trained four times per week over four weeks of intensified training (in addition to their usual technical-tactical judo training; CG underwent only the usual training) followed by 12 days of tapering. The countermovement jump test (CMJ), isometric and dynamic judogi chin-up tests (JCT), uchi-komi speed test (UST), Special Judo Fitness Test (SJFT) and Judo Physical Fitness Test (JPFT) were administered before and after the intensified period and after tapering. The CMJ performance was superior in KG compared with UG, RG and CG. Isometric JCT performance was superior in KG compared with RG and CG. Regarding UST, performance was superior in UG compared with RG and CG. The same performance was superior with respect to the same groups considering pre-training to tapering change. The SJFT index did not differ between groups or time-points. The JPFT index increased after intensified and tapering periods compared with before training, with KG eliciting higher values compared with CG. Coaches and conditioning coaches could administer kumi-kata high-intensity interval training to enhance athletes' judo-specific physical fitness.

Effects of combat sports on functional network connectivity in adolescents.

PURPOSE: To explore the effects of combat sports on functional network connectivity (FNC) in healthy adolescents. METHODS: Resting-state fMRI data were acquired from the combat sports (CS) group (n = 32) and non-athlete healthy control (HC) group (n = 29). Resting-state networks (RSNs) were obtained based on independent component analysis (ICA), and FNC analysis was performed. Then, the intra-network and inter-network connections were compared between the two groups. RESULTS: Compared with the HC group, the CS group demonstrated increased intra-network FC within the sensorimotor network (SMN), visual network (VIN), and cerebellum network (P < 0.01, FDR correction). Besides, decreased inter-network FC was found in the SMN-VIN, SMN-auditory network, SMN-default mode network, attention network (AN)-VIN, and AN-executive control network connections (P < 0.01, FDR correction). CONCLUSION: This study showed a complex relationship between combat sports and FNC in adolescents. The observed FNC patterns in the CS group may reflect training-related brain network optimization, early signs of subclinical brain damage, or preexisting differences. The extensive effects of combat sports on FNC in adolescents could expand our understanding of neuromodulatory mechanisms.

Hypoxic re-exposure retains hematological but not performance adaptations post-altitude training.

PURPOSE: To test the hypothesis that hypoxic re-exposure after return from natural altitude training is beneficial in retaining hematological and performance adaptations. METHODS: Eighteen mixed martial art fighters completed a 3-weeks natural altitude training camp at 2418 m. Afterwards, participants were randomly assigned to a living high-training low (12 h/d at a simulated altitude of 2800 m) group (LHTL, n = 9) or a living low-training low group (LLTL, n = 9) for a 3-week sea-level training period. At baseline and after return to sea level, hematological [hemoglobin mass (Hbmass) on days 2, 6, 9, 12, 15 and 21] and performance (3000 m time trial and maximal oxygen uptake on days 4, 6, 9, 15 and 21) markers were assessed. RESULTS: Mean Hbmass increased from baseline to day 2 (11.7 ± 0.9 vs. 12.4 ± 1.3 g/kg; + 6.6 ± 7.5%; P < 0.05). While Hbmass remained elevated above baseline in LHTL (P < 0.001), it returned near baseline levels from day 9 in LLTL. Irrespective of groups, mean V̇O2max was only elevated above baseline at day 2 (+ 4.5 ± 0.8%) and day 9 (+ 3.8 ± 8.0%) (both P < 0.05). Compared to baseline, 3000 m running time decreased at day 4 (- 3.1 ± 3.3%; P < 0.05) and day 15 (- 2.8 ± 2.3%; P < 0.05) only. CONCLUSIONS: Despite re-exposure to hypoxia allowing a recovery of the hypoxic stimulus to retain Hbmass gains from previous altitude sojourn, there is no performance advantage of this practice above sea level residence. Our results also give support to empirical observations describing alternance of periods of optimal and attenuated performance upon return to sea level.

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.

A 5-Year Analysis of Weight Cycling Practices in a Male World Champion Professional Boxer: Potential Implications for Obesity and Cardiometabolic Disease.

Weight cycling is thought to increase the risk of obesity and cardiometabolic disease in nonathletic and athletic populations. However, the magnitude and frequency of weight cycling is not well characterized in elite athletes. To this end, we quantified the weight cycling practices of a male World Champion professional boxer competing at super middleweight (76.2 kg). Over a 5-year period comprising 11 contests, we assessed changes in body mass (n = 8 contests) and body composition (n = 6 contests) during the training camp preceding each contest. Time taken to make weight was 11 ± 4 weeks (range: 4-16). Absolute and relative weight loss for each contest was 12.4 ± 2.1 kg (range: 9.8-17.0) and 13.9% ± 2.0% (range: 11.3-18.2), respectively. Notably, the athlete commenced each training camp with progressive increases in fat mass (i.e., 12.5 and 16.1 kg for Contests 1 and 11) and reductions in fat-free mass (i.e., 69.8 and 67.5 kg for Contests 1 and 11, respectively). Data suggest that weight cycling may lead to "fat overshooting" and further weight gain in later life. Larger scale studies are now required to characterize the weight cycling practices of elite athletes and robustly assess future cardiometabolic disease risk. From an ethical perspective, practitioners should be aware of the potential health consequences associated with weight cycling.

Pre-competition body mass loss characteristics of Brazilian jiu-jitsu competitors in the United Kingdom.

BACKGROUND: Brazilian jiu-jitsu (BJJ) is a grappling-based combat sport in which competitors engage in pre-competition acute 'weight' loss (AWL) and rapid 'weight' loss (RWL) to achieve the body mass (BM) required for their desired division. AWL/RWL practices of UK BJJ competitors have not previously been reported. AIM: Our aim in this study was to determine the prevalence, magnitude and stakeholder influences of AWL and RWL amongst BJJ participants in the United Kingdom (UK). A secondary aim was to explore whether there is any influence of time spent in the sport or competition frequency on AWL/RWL practices. METHODS: In this study we used the rapid weight loss questionnaire (RWLQ) adapted for BJJ to determine the prevalence and magnitude of AWL/RWL in UK BJJ, the prevalence of methods used and the key stakeholder influences on these practices. As a secondary investigation we aimed to determine whether there was any effect of age starting BJJ on AWL/RWL. RESULTS: Of 115 completed responses, 59% stated they performed AWL/RWL before competition. Mean BM loss for this competition was 1.9 ± 3.8 kg (2.3 ± 4.6%), with 34% of participants starting BM loss 3-7 days prior and 16% starting 0-2 days prior. Methods used tend to be achieving calorie deficit via exercise and diet rather than hypohydration, with little advice from formally qualified personnel. Participants who perform AWL/RWL started training (BF10 = 199, d = .72) and competing (BF10 = 107, d = .68) in BJJ younger than those who do not perform AWL/RWL. CONCLUSIONS: AWL/RWL is prevalent in UK BJJ, but not at the magnitude of other combat sports or countries. Though negative effects of extreme hypohydration are unlikely, there may be a higher chance of eating disorders in BJJ, particularly due to the young age of AWL/RWL commencement.

Does weight change relate to psychological variables and eating behaviours in combat sports?

PURPOSE: Athletes who perform combat sports tend to engage in weight-management strategies to fit in a specific weight class that are characterized by disordered eating behaviours. This study aimed to (1) characterize eating behaviours and adaptation to stress regarding an unwanted weight change before a competition; (2) evaluate the differences between athletes who consider unwanted weight changes as a challenge or as a threat in regard to emotions, coping strategies and eating behaviours; and (3) evaluate whether some of these variables related to the unwanted weight change (e.g., emotions, cognitive appraisal of the situation) are predictors of disordered eating behaviours in combat sports. METHODS: A total of 166 combat sports athletes (75.3% male), aged between 14 and 56 years (M = 22.73; SD = 8.03), filled out a set of questionnaires that evaluated personal variables, cognitive appraisal (threat/challenge), coping, emotions, and eating behaviours related to an unwanted weight change before a competition. RESULTS: Most of the athletes (57.3%) reported high levels of stress related to the experience of an unwanted weight change before a competition. Athletes who perceived this experience as more of a threat had significantly more eating concerns, anxiety, dejection, anger, active confrontation and emotional support. Athletes who perceived it as more of a challenge experienced more excitement and happiness. Athletes who perceived a high threat and low challenge experienced significantly increased anxiety levels and athletes who perceived this experience as a low threat and the low challenge had decreased anxiety. The desire to weigh less, the perception of a threat regarding weight changes, the ability to cope with denial, and anxiety emerged as predictors of disordered eating behaviours. CONCLUSION: To prevent or reduce disordered eating behaviours, it is important to promote adequate strategies to deal with weight changes before a competition and, consequently, positive emotions among sports combat athletes. LEVEL OF EVIDENCE: Level III, case-control analytic study.

Genetic basis of elite combat sports athletes: a systematic review.

Each athlete's innate talent is widely recognized as one of the important contributors to achievement in athletic performance, and genetic factors determine a significant portion of talent or traits. Advances in DNA sequencing technology allow us to discover specific genetic variants contributing to these traits in sports performance. The objective of this systematic review is to identify genes that may play a significant role in the performance of elite-level combat sports athletes. Through the review of 18 full-text articles, a total of 109 different polymorphisms were investigated in 14,313 participants (2,786 combat sports athletes, 8,969 non-athlete controls, 2,558 other sports athletes). Thirteen polymorphisms showed a significant difference between elite combat athletes and the control group, and consist of 8 (PPARA rs4253778, ACTN3 rs1815739, ACE rs4646994, CKM rs8111989, MCT1 rs1049434, FTO rs9939609, GABPß1 rs7181866 and rs8031031) oriented to athletic performance and 5 (COMT rs4680, FEV rs860573, SLC6A2 rs2242446, HTR1B rs11568817, ADRA2A rs521674) focused on psychological traits including emotional and mental traits in combat sports athletes. In addition, a recent whole genome sequencing study identified 4 polymorphisms (KIF27 rs10125715, APC rs518013, TMEM229A rs7783359, LRRN3 rs80054135) associated with reaction time in wrestlers. However, it is not clearly identified which genes are linked explicitly with elite combat sports athletes and how they affect the elite athlete's status or performance in combat sports. Hence, a greater number of candidate genes should be included in future studies to practically utilize the genetic information.

Psycho-physiological aspects of small combats in taekwondo: impact of area size and within-round sparring partners.

The study investigated physiological and psychological responses to taekwondo combat sessions as a function of different area sizes and within-round sparring partners. Twenty-four adolescent (age: 17 ± 1years) male (n = 12) and female (n = 12) taekwondo athletes participated in the study. Each athlete confronted 1 (1vs.1; no sparring partner change) or 2 (1vs.2; within-round sparring partner change every minute) opponents in different area sizes (i.e., 4 × 4 m, 6 × 6 m, and 8 × 8 m) for 2 min. Blood lactate concentration ([La]) was measured before and after bouts. Heart rate (HR) was measured throughout the contests and rating of perceived exertion was assessed after bouts. Mean HR (HRmean) and percentage of maximum HR (%HRmax) determined during a 20-m multistage shuttle run test were used for analysis. Mood states were assessed before and after bouts and physical enjoyment was analyzed after bouts. The results showed higher HRmean and %HRmax values for the 1vs.1 compared to the 1vs.2 condition (p < 0.001) and [La] values were higher at post-combat measurements (p < 0.001). Moreover, tension and fatigue were higher in 6 × 6 m compared with 8 × 8 m (p = 0.022 and p = 0.023, respectively) and anger was higher in 6 × 6 m and 8 × 8 m in comparison with 4 × 4 m (p = 0.012 and p = 0.043, respectively). Confusion increased from before to after bouts (p < 0.001), from 4 × 4 m and 6 × 6 m area sizes to 8 × 8 m (p = 0.001 and p = 0.018, respectively), and from 1vs.1 to 1vs.2 (p < 0.001). Furthermore, vigour decreased from before to after bouts (p < 0.01). Taekwondo combat sessions are a specific conditioning exercise for athletes. Thus, coaches can use the 1vs.1 condition to elicit higher HR responses and 6 × 6 m area size to induce higher psychological stress, mimicking what occurs during a competition.