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The purpose of this study was to check the chance of winning an Olympic medal considering the participation or not in the World Championship and the outcome in case of participation. We analyzed a total of 390 athletes (200 males and 190 females) competing in the Olympic Games. A logistic regression was used to measure the magnitude of association between winning a medal in the Olympic Games and participation in the World Championships. The odds ratio of winning a medal in the Olympic Games was 12.7, 21.2 and 8.2 times greater for World Championship medallists when compared to non-medallists in the World Championship for all athletes, females only, and males only, respectively. Furthermore, high-level athletes who did not compete in the World Championship had also increased odds ratio of winning an Olympic medal compared to those who participated in the World Championship with no medal: this was 6.6 times greater for the whole group, 6.7 for females only and 6.5 for males only. Our results show that increased odds ratios of winning an Olympic medal were found for judo athletes competing in the World Championship and winning a medal in it, as well as for those avoiding this competition. [ABSTRACT FROM AUTHOR]

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Study aim: Martial arts and combat sports have been an alternative for individuals seeking the health benefits of physical activity and exercise, but little is known about its practitioners’ quality of life. Therefore, this study aimed to investigate the quality of life of practitioners of five of the most common modalities in Brazil.

Kickboxing is one of the modern combat sports. The psychophysiological demands of a kickboxing competition require athletes to achieve high thresholds of several aspects of physical fitness. The aim of the current review is to critically analyse and appraise the kickboxer's anthropometric, physiological, physical and psychological attributes with the activity profile and injury epidemiology in order to provide practical recommendations for training as well as new areas of scientific research. The available information shows that both amateur and elite-level male kickboxers are characterized by a higher proportion of mesomorphy with a well-developed muscle mass and low body fat percentage. While there is some variation in the maximum oxygen uptake of kickboxers, moderate to high cardio-respiratory levels are reported for these athletes. Regardless of kickboxers' level, a high peak and mean anaerobic power output were reported. High-level kickboxing performance also requires well-developed muscle power in both the upper and lower limbs. Psychological factors contribute to success that requires high levels of self-confidence, motivation, dispositional hope and optimism, mental toughness/resiliency, and adaptive perfectionism. Psychological attributes also distinguished successful from less successful kickboxers. The activity-to-rest ratio was higher in elite (1:1) than both amateur and national-level (from 1:2 to 1:5) kickboxers, with no significant differences between rounds (round 1 =1:4, and rounds 2 and 3 = 1:5) as well as between winners and losers in amateur and national-level simulated combats. These particular psychophysiological characteristics and performance aspects of kickboxers influence performance and could serve as guidance for training. Finally, kickboxing is characterized by chronic repetitive head trauma, which causes hypopituitarism due to traumatic brain injury (TBI). Future investigations into the physical, physiological and psychological characteristics related to age, gender and competitive levels of kickboxers are required to enrich the current knowledge and to help create the most suitable training programme. [ABSTRACT FROM AUTHOR]

Human performance efficiency and effectiveness in different sports depend to a large extent on the size, weight and proportion of the physique of the athlete. The aim of this study was to identify morphological characteristics of Brazilian Jiu-Jitsu (BJJ) athletes. The sample consisted of 25 highly trained male athletes who were classified according to their fighting style; guard fighter (GF) vs. pass fighter (PF). The athletes were assessed for somatotype, body composition and proportionality. For the whole group of athletes the somatotype was 2.23±0.68, 6.33±1.14, and 1.75±0.87 for endomorph, mesomorph and ectomorph components, respectively. Muscle and adipose tissue percentages were 52.34±2.15% and 19.30±2.51%, respectively. PF were significantly more mesomorph (p< 0.05) and less ectomorph (p< 0.05) than GF. Also, PF had significantly higher phantom Z score for bone mass vs. GF (0.51±0.57 vs. 0.01±0.54; p<0.05), and significantly lower muscle mass- bone mass ratio (4.55±0.31 vs. 4.77±0.56; p<0.05), height (1.71±0.06 vs. 1.77±0.07; p<0.05) and height weight ratio (40.58±1.11 vs. 41.84±1.22). Our results show that morphological characteristics are related to different fighting styles in BJJ athletes. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study was to examine the influence of karate practice level (national vs international level) and sex (women vs men) on physiological and perceptual responses in three modern karate training modalities (tactical-technical (TT), technical-development (TD), and randori). Method: The study included 18 karatekas participating in an eight-session training camp of four TT, two TD, and two randori. During each session, the percentage of maximal heart rate (HR), blood lactate concentration [La-], and rating of perceived exertion (RPE) were assessed. Results: The main results showed that the percentage of maximal HR was significantly higher in women than in men regardless of practice level or training modality (70.3 ± 4.1 vs 66.2 ± 6.3, respectively). Moreover, [La-] and RPE were significantly lower in international-level karatekas compared with their national-level counterparts whatever the sex or training modality ([La-] = 11.4 ± 2.6 vs 8.3 ± 2.4 mmol · L-1and RPE = 3.6 ± 1.2 vs 4.3 ± 1.5, respectively). Last, physiological and perceptual responses were significantly higher during randori in comparison with TT and TD for both sexes. Conclusion: The combination of [La-] and RPE thus seems to be a good indicator for discriminating between national- and international-level karatekas, and randori seems to be an effective means to reproduce official karate sparring. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the performance, as well as neuromuscular activity, in a strength task in subjects with different training backgrounds. Participants (n = 26) were divided into three groups according to their training backgrounds (aerobic, strength or mixed) and submitted to three sessions: (1) determination of the maximum oxygen uptake during the incremental treadmill test to exhaustion and familiarization of the evaluation of maximum strength (1RM) for the half squat; (2) 1RM determination; and (3) strength exercise, four sets at 80% of the 1RM, in which the maximum number of repetitions (MNR), the total weight lifted (TWL), the root mean square (RMS) and median frequency (MF) of the electromyographic (EMG) activity for the second and last repetition were computed. There was an effect of group for MNR, with the aerobic group performing a higher MNR compared to the strength group (P = 0.045), and an effect on MF with a higher value in the second repetition than in the last repetition (P = 0.016). These results demonstrated that individuals with better aerobic fitness were more fatigue resistant than strength trained individuals. The absence of differences in EMG signals indicates that individuals with different training backgrounds have a similar pattern of motor unit recruitment during a resistance exercise performed until failure, and that the greater capacity to perform the MNR probably can be explained by peripheral adaptations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare performance and physiological responses during arm and leg aerobic power tests of combat duration in male child, cadet and senior judo athletes. Power output and physiological parameters, i.e., peak oxygen uptake (VO2peak), peak ventilation, peak heart rate, lactate, and rate of perceived exertion, of 7 child (under 15 years: age class U15, 12.7 ± 1.1 yrs), 10 cadet (U17, 14.9 ± 0.7 yrs) and 8 senior (+20, 29.3 ± 9.2 yrs) male judo athletes were assessed during incremental tests of combat duration on an arm crank and a cycle ergometer. Children as well as cadets demonstrated higher upper body relative VO2peak than seniors (37.3 ± 4.9, 39.2 ± 5.0 and 31.0 ± 2.1 ml∙kg-1∙min-1, respectively); moreover, upper and lower body relative VO2peak decreased with increasing age (r = -0.575, p < 0.003 and r = -0.580, p < 0.002, respectively). Children showed lower blood lactate concentrations after cranking as well as after cycling when compared to seniors (7.8 ± 2.4 vs. 11.4 ± 2.1 mmol∙l-1 and 7.9 ± 3.0 vs. 12.0 ± 1.9 mmol∙l-1, respectively); furthermore, blood lactate values after cranking increased with age (r = 0.473, p < 0.017). These differences should be considered in planning the training for judo athletes of different age classes. [ABSTRACT FROM AUTHOR]

Objective: Although some scientific information on electronic body protectors in taekwondo is available, no research has been done to assess the impact of kicks in a competitive situation. The purpose of this study, then, was to assess the energy absorbed by these protectors from kicks performed in an actual taekwondo competition. Methods: Subjects consisted of junior (14-17 years) and senior (?18 years) male taekwondo-in, who participated in an open tournament. Data on the energy imparted by valid kicks in Joules (J) were collected from a public visual electronic monitor. Results: Energy was higher for the seniors: 264.31 ± 56.63 J versus 224.38 ± 48.23 J for the juniors (eta2 = 0.121). The seniors scored lower in percent impact but the effect was trivial: 123.46 ± 24.77% versus 136.70 ± 26.33% (eta2 = 0.087). Conclusions: The difference between senior and junior taekwondo-in in absolute energy generated was small, while the difference in relative energy impact was trivial in favour of the junior taekwondo athletes. [ABSTRACT FROM AUTHOR]

This study compared measurements of upper body aerobic fitness in elite (EC; n = 7) and intermediate rock climbers (1C; n = 7), and a control group (C; n = 7). Subjects underwent an upper limb incremental test on hand cycle ergometer, with increments of 23 W-min"1, until exhaustion. Ventilation (VE) data were smoothed to 10 s averages and plotted against time for the visual determination of the first ( VT1 ) and second (VT2) ventilatory thresholds. Peak power output was not different among groups [EC= 130.9 (±11.8) W; 1C=122.1 (±28.4) W; C = 115.4 (±15.1) W], but time to exhaustion was significantly higher in EC than 1C and C. VO2Peai< was significantly higher in EC [36.8 (±5.7) mLkg-1.min-1] and IC [35.5 (±5.2) mLkg-'.mirT1] than C [28.8 (±5.0) mL.kg-1.min-1], but there was no difference between EC and IC. VT1 was significantly higher inECthanC[EC=69.0(±9.4)W;lC = 62.4(±13.0) W; C = 52.1 (±11.8) W], but no significant difference was observed in VT2 [EC = 103.5 (±18.8) W; IC = 92.0 (±22.0) W; C=85.6 (±19.7) W]. These results show that elite indoor rock climbers elicit higher aerobic fitness profile than control subjects when measured with an upper body test. [ABSTRACT FROM AUTHOR]

The objective of this study was to propose an alternative method (MAODALT) to estimate the maximal accumulated oxygen deficit (MAOD) using only one supramaximal exhaustive test. Nine participants performed the following tests: (a) a maximal incremental exercise test, (b) six submaximal constant workload tests, and (c) a supramaximal constant workload test. Traditional MAOD was determined by calculating the difference between predicted O2 demand and accumulated O2 uptake during the supramaximal test. MAODALT was established by summing the fast component of excess post-exercise oxygen consumption and the O2 equivalent for energy provided by blood lactate accumulation, both of which were measured during the supramaximal test. There was no significant difference between MAOD (2.82 ± 0.45 L) and MAODALT (2.77 ± 0.37 L) (p=0.60). The correlation between MAOD and MAODALT was also high (r=0.78; p=0.014). These data indicate that the MAODALT can be used to estimate the MAOD. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine physiological, nutritional, and performance profiles of elite Olympic Wushu (kung-fu) athletes. Ten men and four women elite athletes took part in the study. They completed the following tests: body composition, nutritional assessment, upper-body Wingate Test, vertical jump, lumbar isometric strength, and flexibility. Blood lactate was determined at rest and after the Wingate Test. Blood lactate was also determined during a training session (combat and Taolu training). We found low body fat (men: 9.5 +/- 6.3%; women: 18.0 +/- 4.8%), high flexibility (sit-and-reach-men: 45.5 +/- 6.1 cm; women: 44.0 +/- 6.3 cm), high leg power (vertical jump-men: 37.7 +/- 8.4 cm; women: 32.3 +/- 1.1 cm), high lumbar isometric strength (men: 159 +/- 13 cm; women: 94 +/- 6 cm), moderate arm mean and peak power (Wingate Test-men: 4.1 +/- 0.4 and 5.8 +/- 0.5 Wxkg, respectively; women: 2.5 +/- 0.3 and 3.4 +/- 0.3 W.kg, respectively), and elevated blood lactate after the Wingate Test (men: 10.8 +/- 2.0 mmolxL; women: 10.2 +/- 2.0 mmolxL) and during training (combat: 12.0 +/- 1.8 mmolxL; Taolu: 7.7 +/- 3.3 mmolxL). Men athletes consume a high-fat, low-carbohydrate diet, whereas women consume a moderate, high-carbohydrate diet. Energy consumption was markedly variable. In conclusion, Olympic Wushu seems to be a highly anaerobic-dependent combat sport. Low body fat, high flexibility, leg anaerobic power, isometric strength, and moderately high arm anaerobic power seem to be important for successful competitive performance. [ABSTRACT FROM AUTHOR]

A Feynman-Kac formula for Schro¨dinger operators including a one-center point interaction in R3 plus a bounded potential is proved. Functional integration methods on similar Kac's averages with point interactions allow us to construct bounded self-adjoint semigroups in L2(R3), with bounded below Schrodinger generators, when V+ ∊ Lloc2 and V− belongs to a large class of L2 + L−8 potentials. Moreover, a pointwise bound on the range of the semigroup is given. [Copyright &y& Elsevier]

Abstract: Objective: The objective of this work was to verify if there was a difference in throwing speed performance between heavier and lighter weight categories in judo. Methods and subjects: Sixteen (16) judoists 18±3 years old, eight considered in the lightweight category (<66kg) and eight considered in the heavyweight (>73kg) category, participated in the study after signing a term of informed consent. A force–velocity test was used to determine the anaerobic power, strength, and pedal speed for each subject. In addition, three trials of Nage-komi exercise, each comprised of a set of Osoto-gari (15s), Uchi-mata (15s) and Seoi-nage (15s) throws were performed by each subject to ascertain throwing speed. Throws within the sets were intersected by one period of three minutes passive rest, while the trials were separated by one period of 10 minutes passive rest. Heart rate and the greatest number of throws within each set were measured for three trials. One-way analysis of variance (Anova) was used to compare the number of throws between the two weight categories and a “Student” test when the difference was significant. A correlation was used to examine the link between the different parameters. Results: The force–velocity test did not show a significant difference in pedal speed between the two categories. However, there was a significant difference between the two categories when throwing speed was measured by the number of throws (p <0.05) executed during the Seoi-nage (p <0.01) and Uchi-mata (p <0.05) techniques. There was however, no significant difference between the two categories in Osoto-gari technique. Conclusion: The throwing speed of judoists represented by the number of throws is significantly different between the two categories. The lighter category has more speed than the heavier category using the arm technique (Seoi-nage), while the heavier category has more speed using the leg technique with half turn of the attacker''s body (Uchi-mata). As a result, throwing speed is related to the type of technique used and not weight category. [Copyright &y& Elsevier]

Abstract Judo competitions are divided into weight classes. However, most athletes reduce their body weight in a few days before competition in order to obtain a competitive advantage over lighter opponents. To achieve fast weight reduction, athletes use a number of aggressive nutritional strategies so many of them place themselves at a high health-injury risk. In collegiate wrestling, a similar problem has been observed and three wrestlers died in 1997 due to rapid weight loss regimes. After these deaths, the National Collegiate Athletic Association had implemented a successful weight management program which was proven to improve weight management behavior. No similar program has ever been discussed by judo federations even though judo competitors present a comparable inappropriate pattern of weight control. In view of this, the basis for a weight control program is provided in this manuscript, as follows: competition should begin within 1 hour after weigh-in, at the latest; each athlete is allowed to be weighed-in only once; rapid weight loss as well as artificial rehydration (i.e., saline infusion) methods are prohibited during the entire competition day; athletes should pass the hydration test to get their weigh-in validated; an individual minimum competitive weight (male athletes competing at no less than 7% and females at no less than 12% of body fat) should be determined at the beginning of each season; athletes are not allowed to compete in any weight class that requires weight reductions greater than 1.5% of body weight per week. In parallel, educational programs should aim at increasing the athletes', coaches' and parents' awareness about the risks of aggressive nutritional strategies as well as healthier ways to properly manage body weight.

Background and objective Inadequate sleep patterns may be considered a trigger to development of several metabolic diseases. Additionally, sleep deprivation and poor sleep quality can negatively impact performance in exercise training. However, the impact of sleep duration and sleep quality on performance during incremental maximal test performed by healthy men is unclear. Therefore, the purpose of the study was to analyze the association between sleep pattern (duration and quality) and performance during maximal incremental test in healthy male individuals. Methods A total of 28 healthy males volunteered to take part in the study. Sleep quality, sleep duration and physical activity were subjectively assessed by questionnaires. Sleep pattern was classified by sleep duration (> 7 h or < 7 h of sleep per night) and sleep quality according to the sum of measured points and/or scores by the Pittsburgh Sleep Quality Index (PSQI). Incremental exercise test was performed at 35 watts for untrained subjects, 70 watts for physically active subjects and 105 watts for well-trained subjects. Results HR max was correlated with sleep quality (r = 0.411, p = 0.030) and sleep duration (r = − 0.430, p = 0.022). Participants reporting good sleep quality presented higher values of W max , VO 2max and lower values of HR max when compared to participants with altered sleep. Regarding sleep duration, only W max was influenced by the amount of sleeping hours per night and this association remained significant even after adjustment by VO 2max . Conclusion Sleep duration and quality are associated, at least in part, with performance during maximal incremental test among healthy men, with losses in W max and HR max . In addition, our results suggest that the relationship between sleep patterns and performance, mainly in W max , is independent of fitness condition. [ABSTRACT FROM AUTHOR]

Oculopharyngeal Muscular Dystrophy (OPMD) is a myopathy characterize by ptosis and marked swallowing impairment. Dysphagia may also occur in some mitochondrial diseases. Previous reports focused on the proximal (skeletal) parts of oesophagus only. We tried to analyse proximal and distal oesophageal function and the role of parasympathetic system and myenteric plexus in such disorders. Four male dysphagic patients, 3 affected by sporadic OPMD and 1 with single mitochondrial DNA deletion and “OMPD- like” phenotype, were studied. Both adrenergic and cholinergic functions of autonomic system were investigated. High resolution manometry with 22 perfused channels was used to assess the oesophageal function. Beside the involvement of the proximal portion of the oesophagus (striated muscle), smooth muscles seemed also to be affected in OPMD patients; normal peristaltic waves were found in only about 50% of swallows. In the patient with mitochondrial DNA deletion absent peristalsis involving both striated and smooth muscle in 100% of swallows was observed. Since autonomic tests were normal in all patients, progressive reduction of peristalsis in the oesophageal distal part could be related to myenteric plexus derangement or to smooth cell muscle disease. [ABSTRACT FROM AUTHOR]