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The Journal of Visualized Experiments (JoVE) is a peer reviewed, PubMed-indexed video journal. Our mission is to increase the productivity of scientific research.

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Articles by Emerson Franchini in JoVE

 JoVE General

Fastställande av bidrag Energy Systems under träning


JoVE 3413 3/20/2012

1, 2, 1,3, 1, 1, 4

1Laboratory of Applied Nutrition, School of Physical Education and Sport, University of Sao Paulo, 2Aerobic Performance Research Group, School of Physical Education and Sport, University of Sao Paulo, 3Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of Sao Paulo, 4Martial Arts and Combat Sports Research Group, School of Physical Education and Sport, University of Sao Paulo

Detta protokoll möjliggör forskare inriktade på motion och idrott vetenskaperna för att bestämma den relativa bidrag av tre olika energisystem till den totala energiförbrukningen under en stor variation av övningar.

Other articles by Emerson Franchini on PubMed

Specificity of Practice in Acquisition of the Technique of O-soto-gari in Judo

Perceptual and Motor Skills. Dec, 2002  |  Pubmed ID: 12578266

Retention and transfer of the technique of o-soto-gari by 32 9-yr.-old children was optimized by conditions of acquisition similar to those of competition.

Physical Fitness and Anthropometrical Profile of the Brazilian Male Judo Team

Journal of Physiological Anthropology. Mar, 2007  |  Pubmed ID: 17435345

The present study had as objectives (1) to compare the morphological and functional characteristics of the male judo players of the Brazilian Team A (n=7) with the judo players of Teams B and C (reserves; n=15), and (2) to verify the association between the variables measured. Thus, 22 athletes from the seven Olympic weight categories were submitted to: a body composition evaluation (body mass, height, ten skinfolds, eight circumferences, three bone diameters and percent body fat estimation); the Special Judo Fitness Test (SJFT); maximal strength tests (one repetition-maximum, 1 RM, in bench press, row, and squat); and the Cooper test. One-way analysis of covariance was used to compare the groups. The relationships between variables were determined by the Pearson coefficient correlation. The significance level was fixed at 5%. No significant difference was found in any variable between them. The main significant correlations observed were between the following variables: VO2max and number of throws in the SJFT (r=0.79); percent body fat and estimated VO2max (r=-0.83) and number of throws in the SJFT (r=-0.70); chest circumference and bench press 1 RM (r=0.90) and in the row (r=0.80); and thigh circumference and squat 1 RM (r=0.86). However, there was no significant correlation between circumferences and 1 RM/kg of body mass. According to these results the main conclusions are: (1) the physical variables measured do not discriminate performance when analysis is directed to the best athletes; (2) a higher percent body fat is negatively correlated with performance in activities with body mass locomotion (Cooper test and the SJFT); (3) judo players with higher aerobic power performed better in high-intensity intermittent exercise; (4) judo players with bigger circumferences present bigger absolute maximal strength.

Energy System Contributions in Indoor Rock Climbing

European Journal of Applied Physiology. Oct, 2007  |  Pubmed ID: 17602238

The present study cross-sectionally investigated the influence of training status, route difficulty and upper body aerobic and anaerobic performance of climbers on the energetics of indoor rock climbing. Six elite climbers (EC) and seven recreational climbers (RC) were submitted to the following laboratory tests: (a) anthropometry, (b) upper body aerobic power, and (c) upper body Wingate test. On another occasion, EC subjects climbed an easy, a moderate, and a difficult route, whereas RC subjects climbed only the easy route. The fractions of the aerobic (W(AER)), anaerobic alactic (W(PCR)) and anaerobic lactic (W[La(-)]) systems were calculated based on oxygen uptake, the fast component of excess post-exercise oxygen uptake, and changes in net blood lactate, respectively. On the easy route, the metabolic cost was significantly lower in EC [40.3 (6.5) kJ] than in RC [60.1 (8.8) kJ] (P < 0.05). The respective contributions of the W (AER), W (PCR), and W[La(-)] systems in EC were: easy route = 41.5 (8.1), 41.1 (11.4) and 17.4% (5.4), moderate route = 45.8 (8.4), 34.6 (7.1) and 21.9% (6.3), and difficult route = 41.9 (7.4), 35.8 (6.7) and 22.3% (7.2). The contributions of the W (AER), W (PCR), and W[La(-)] systems in RC subjects climbing an easy route were 39.7 (5.0), 34.0 (5.8), and 26.3% (3.8), respectively. These results indicate that the main energy systems required during indoor rock climbing are the aerobic and anaerobic alactic systems. In addition, climbing economy seems to be more important for the performance of these athletes than improved energy metabolism.

Acute Effect of Two Aerobic Exercise Modes on Maximum Strength and Strength Endurance

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Nov, 2007  |  Pubmed ID: 18076237

The purpose of this study was to evaluate the effects of 2 modes of aerobic exercise (continuous or intermittent) on maximum strength (1 repetition maximum, 1RM) and strength endurance (maximum repetitions at 80% of 1RM) for lower- and upper-body exercises to test the acute hypothesis in concurrent training (CT) interference. Eight physically active men (age: 26.9 +/- 4.2 years; body mass: 82.1 +/- 7.5 kg; height: 178.9 +/- 6.0 cm) were submitted to: (a) a graded exercise test to determine V(.-)O2max (39.26 +/- 6.95 ml x kg(-1) x min(-1)) and anaerobic threshold velocity (3.5 mmol x L(-1)) (9.3 +/- 1.27 km x h(-1)); (b) strength tests in a rested state (control); and (c) 4 experimental sessions, at least 7 days apart. The experimental sessions consisted of a 5-kilometer run on a treadmill continuously (90% of the anaerobic threshold velocity) or intermittently (1:1 minute at V(.-)O2max). Ten minutes after the aerobic exercise, either a maximum strength or a strength endurance test was performed (leg press and bench press exercises). The order of aerobic and strength exercises followed a William's square distribution to avoid carryover effects. Results showed that only the intermittent aerobic exercise produced an acute interference effect on leg strength endurance, decreasing significantly (p < 0.05) the number of repetitions from 10.8 +/- 2.5 to 8.1 +/- 2.2. Maximum strength was not affected by the aerobic exercise mode. In conclusion, the acute interference hypothesis in concurrent training seems to occur when both aerobic and strength exercises produce significant peripheral fatigue in the same muscle group.

Technical Variation in a Sample of High Level Judo Players

Perceptual and Motor Skills. Jun, 2008  |  Pubmed ID: 18712208

Technical actions performed by two groups of judokas who won medals at World Championships and Olympic Games during the period 1995-2001 were analyzed. In the Super Elite group (n = 17) were the best athletes in each weight category. The Elite group (n = 16) were medal winners who were not champions and did not win more than three medals. Super Elite judokas used a greater number of throwing techniques which resulted in scores, even when expressed relative to the total number of matches performed, and these techniques were applied in more directions than those of Elite judokas. Further, the number of different throwing techniques and the variability of directions in which techniques were applied were significantly correlated with number of wins and the number of points and ippon scored. Thus, a greater number of throwing techniques and use of directions for attack seem to be important in increasing unpredictability during judo matches.

Physiological, Performance, and Nutritional Profile of the Brazilian Olympic Wushu (kung-fu) Team

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jan, 2009  |  Pubmed ID: 19077742

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.

Taekwondo: Physiological Responses and Match Analysis

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jul, 2009  |  Pubmed ID: 19528839

The aim of the present study was to determine the time structure and physiological responses during Songahm Taekwondo (TKD) competition and to compare these variables between winner and non-winner athletes. Fourteen men subjects were analyzed. Blood lactate concentration (LA) and heart rate (HR) were determined before and after the match. The match was filmed for the determination of the number of techniques used, the duration of effort and rest periods (RPs), and the interval between high-intensity movements (HM). Post-match LA was 7.5 +/- 3.8 mmol x L(-1), HR was 183 +/- 9 b.x min(-1), and HM was 31 +/- 16 seconds. The mean effort time (8 +/- 2 seconds) did not differ from mean interval time (8 +/- 3 seconds). Winners used a smaller total number of techniques, but post-match LA or HR did not differ from that of non-winners. In conclusion, the glycolytic metabolism was not the predominant energy source and the physiological responses did not differ between winners and non-winners. Coaches and sports scientists should prepare a technical or physical training session considering the low glycolytic contribution in this sport, hence the training protocol should involve high-intensity movements interspersed with longer RPs to provide the creatine phosphate recovery, with special attention given to the technical quality of TKD skills and not to higher technique volume during a simulation of matches.

Effects of Recovery Type After a Judo Match on Blood Lactate and Performance in Specific and Non-specific Judo Tasks

European Journal of Applied Physiology. Nov, 2009  |  Pubmed ID: 19636586

The objective of the present study was to verify if active recovery (AR) applied after a judo match resulted in a better performance when compared to passive recovery (PR) in three tasks varying in specificity to the judo and in measurement of work performed: four upper-body Wingate tests (WT); special judo fitness test (SJFT); another match. For this purpose, three studies were conducted. Sixteen highly trained judo athletes took part in study 1, 9 in study 2, and 12 in study 3. During AR judokas ran (15 min) at the velocity corresponding to 70% of 4 mmol l(-1) blood lactate intensity (approximately 50% VO(2) peak), while during PR they stayed seated at the competition area. The results indicated that the minimal recovery time reported in judo competitions (15 min) is long enough for sufficient recovery of WT performance and in a specific high-intensity test (SJFT). However, the odds ratio of winning a match increased ten times when a judoka performed AR and his opponent performed PR, but the cause of this phenomenon cannot be explained by changes in number of actions performed or by changes in match's time structure.

Energy Systems Contributions in 2,000 M Race Simulation: a Comparison Among Rowing Ergometers and Water

European Journal of Applied Physiology. Nov, 2009  |  Pubmed ID: 19707782

This study investigated the energy system contributions of rowers in three different conditions: rowing on an ergometer without and with the slide and rowing in the water. For this purpose, eight rowers were submitted to 2,000 m race simulations in each of the situations defined above. The fractions of the aerobic (W (AER)), anaerobic alactic (W (PCR)) and anaerobic lactic (W ([La-])) systems were calculated based on the oxygen uptake, the fast component of excess post-exercise oxygen uptake and changes in net blood lactate, respectively. In the water, the metabolic work was significantly higher [(851 (82) kJ] than during both ergometer [674 (60) kJ] and ergometer with slide [663 (65) kJ] (P < or = 0.05). The time in the water [515 (11) s] was higher (P < 0.001) than in the ergometers with [398 (10) s] and without the slide [402 (15) s], resulting in no difference when relative energy expenditure was considered: in the water [99 (9) kJ min(-1)], ergometer without the slide [99.6 (9) kJ min(-1)] and ergometer with the slide [100.2 (9.6) kJ min(-1)]. The respective contributions of the W (AER), W (PCR) and W ([La-]) systems were water = 87 (2), 7 (2) and 6 (2)%, ergometer = 84 (2), 7 (2) and 9 (2)%, and ergometer with the slide = 84 (2), 7 (2) and 9 (1)%. VO2, HR and lactate were not different among conditions. These results seem to indicate that the ergometer braking system simulates conditions of a bigger and faster boat and not a single scull. Probably, a 2,500 m test should be used to properly simulate in the water single-scull race.

Prevalence, Magnitude, and Methods of Rapid Weight Loss Among Judo Competitors

Medicine and Science in Sports and Exercise. Mar, 2010  |  Pubmed ID: 19952804

To identify the prevalence, magnitude, and methods of rapid weight loss among judo competitors.

Rapid Weight Loss Followed by Recovery Time Does Not Affect Judo-related Performance

Journal of Sports Sciences. Jan, 2010  |  Pubmed ID: 20035492

In this study, we investigated the effects of rapid weight loss followed by a 4-h recovery on judo-related performance. Seven weight-cycler athletes were assigned to a weight loss group (5% body weight reduction by self-selected regime) and seven non-weight-cyclers to a control group (no weight reduction). Body composition, performance, glucose, and lactate were assessed before and after weight reduction (5-7 days apart; control group kept weight stable). The weight loss group had 4 h to re-feed and rehydrate after the weigh-in. Food intake was recorded during the weight loss period and recovery after the weigh-in. Performance was evaluated through a specific judo exercise, followed by a 5-min judo combat and by three bouts of the Wingate test. Both groups significantly improved performance after the weight loss period. No interaction effects were observed. The energy and macronutrient intake of the weight loss group were significantly lower than for the control group. The weight loss group consumed large amounts of food and carbohydrate during the 4-h recovery period. No changes were observed in lactate concentration, but a significant decrease in glucose during rest was observed in the weight loss group. In conclusion, rapid weight loss did not affect judo-related performance in experienced weight-cyclers when the athletes had 4 h to recover. These results should not be extrapolated to inexperienced weight-cyclers.

The Need of a Weight Management Control Program in Judo: a Proposal Based on the Successful Case of Wrestling

Journal of the International Society of Sports Nutrition. 2010  |  Pubmed ID: 20441594

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.

Is Acute Static Stretching Able to Reduce the Time to Exhaustion at Power Output Corresponding to Maximal Oxygen Uptake?

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jun, 2010  |  Pubmed ID: 20508470

This study analyzed the effect of an acute static stretching bout on the time to exhaustion (Tlim) at power output corresponding to VO2max. Eleven physically active male subjects (age 22.3+/-2.8 years, VO2max 2.7+/-0.5 L.min) completed an incremental cycle ergometer test, 2 muscle strength tests, and 2 maximal tests to exhaustion at power output corresponding to VO2max with and without a previous static stretching bout. The Tlim was not significantly affected by the static stretching (164+/-28 vs. 150+/-26 seconds with and without stretching, respectively, p=0.09), but the time to reach VO2max (118+/-22 vs. 102+/-25 seconds), blood-lactate accumulation immediately after exercise (10.7+/-2.9 vs. 8.0+/-1.7 mmol.L), and oxygen deficit (2.4+/-0.9 vs. 2.1+/-0.7 L) were significantly reduced (p

Effect of a Kickboxing Match on Salivary Cortisol and Immunoglobulin A

Perceptual and Motor Skills. Aug, 2010  |  Pubmed ID: 21058596

The hypothesis that salivary cortisol would increase and salivary immunoglobulin A (IgA) decrease after a kickboxing match was tested among 20 male athletes. Saliva samples collected before and after the match were analyzed. Salivary cortisol and salivary IgA concentrations (absolute concentration, salivary IgAabs) and the secretion rate of IgA (salivary IgArate) were measured by enzyme-linked immunosorbent assay. A Wilcoxon test for paired samples showed significant increases in salivary cortisol from pre- to postmatch. No significant changes were observed in salivary IgAabs or secretory IgArate and saliva flow rate. This study indicates that a kickboxing match might increase salivary concentration and thereafter it could be considered a significant source of exercise-related stress. On the other hand, the effect of a kickboxing match on mucosal immunity seems not to be relevant.

Physiological Profiles of Elite Judo Athletes

Sports Medicine (Auckland, N.Z.). Feb, 2011  |  Pubmed ID: 21244106

To be successful in international competitions, judo athletes must achieve an excellent level of physical fitness and physical condition during training. This article reviews the physiological profiles of elite judo athletes from different sex, age and weight categories. Body fat is generally low for these athletes, except for the heavyweight competitors. In general, elite judo athletes presented higher upper body anaerobic power and capacity than non-elite athletes. Lower body dynamic strength seems to provide a distinction between elite and recreational judo players, but not high-level judo players competing for a spot on national teams. Even maximal isometric strength is not a discriminant variable among judo players. However, more studies focusing on isometric strength endurance are warranted. Although aerobic power and capacity are considered relevant to judo performance, the available data do not present differences among judo athletes from different competitive levels. Typical maximal oxygen uptake values are around 50-55 mL/kg/min for male and 40-45 mL/kg/min for female judo athletes. As for other variables, heavyweight competitors presented lower aerobic power values. The typical differences commonly observed between males and females in the general population are also seen in judo athletes when analysing anaerobic power and capacity, aerobic power, and maximal strength and power. However, further research is needed concerning the differences among the seven weight categories in which judo athletes compete.

Relationship Between Attack and Skipping in Taekwondo Contests

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Jun, 2011  |  Pubmed ID: 21512402

The purpose of this study was to determine the relationship between attack time (AT) and skipping time (ST) during the 2007 Taekwondo World Championship and 2008 Beijing Olympic Games. A total of 22 matches (65 rounds, 13 semifinals, and 8 finals) from the World Championship and 23 matches (63 rounds, 22 rounds with 16 athletes each and 1 quarterfinal round) from the Olympic Games, both in the male category, were assessed using time-motion analysis. The AT was considered as the total time during which the athlete attacked or tried to attack, whereas ST was the total time without attempting to attack. The ratio of AT to ST was ∼ 1:7 based on the data pooled from the 2 competitions. The AT/ST ratio was significantly lower for the World Championship than for the Olympic Games (p ≤ 0.05). In the Olympic Games, no consistent differences across weight divisions were found. However, during the World Championship, the heavier weight divisions (>78 kg) exhibited a lower average AT, lower summed AT, lower attack numbers (ANs)and higher average ST than lighter weight divisions (<58 kg, p ≤ 0.05). For both competitions, the ST was lower, and the ANs and AT/ST ratio were higher in round 3 than in round 1 or 2. In conclusion, the results of this study suggest that matches in the Olympic Games were less cadenced than in the World Championship, but that in both competitions, the intensity of the match increased in round 3. Practically, these data suggest that coaches need to structure Taekwondo training sessions in a manner that allows the work/pause ratio to mirror the physical demand imposed during competitions.

A Review of Time-motion Analysis and Combat Development in Mixed Martial Arts Matches at Regional Level Tournaments

Perceptual and Motor Skills. Apr, 2011  |  Pubmed ID: 21667772

Mixed martial arts (MMA) have become a fast-growing worldwide expansion of martial arts competition, requiring high level of skill, physical conditioning, and strategy, and involving a synthesis of combat while standing or on the ground. This study quantified the effort-pause ratio (EP), and classified effort segments of stand-up or groundwork development to identify the number of actions performed per round in MMA matches. 52 MMA athletes participated in the study (M age = 24 yr., SD = 5; average experience in MMA = 5 yr., SD = 3). A one-way analysis of variance with repeated measurements was conducted to compare the type of action across the rounds. A chi-squared test was applied across the percentages to compare proportions of different events. Only one significant difference (p < .05) was observed among rounds: time in groundwork of low intensity was longer in the second compared to the third round. When the interval between rounds was not considered, the EP ratio (between high-intensity effort to low-intensity effort plus pauses) was 1:2 to 1:4. This ratio is between ratios typical for judo, wrestling, karate, and taekwondo and reflects the combination of ground and standup techniques. Most of the matches ended in the third round, involving high-intensity actions, predominantly executed during groundwork combat.

Acute Effects and Postactivation Potentiation in the Special Judo Fitness Test

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Feb, 2011  |  Pubmed ID: 20375739

The purpose of this study was to compare the acute short-term effects of (1) plyometric exercise, (2) combined strength and plyometric exercise (contrast), and (3) maximum strength performance in the Special Judo Fitness Test (SJFT). Eight male judo athletes (mean ± SD, age, 19 ± 1 years; body mass, 60.4 ± 5 kg; height, 168.3 ± 5.4 cm) took part in this study. Four different sessions were completed; each session had 1 type of intervention: (a) SJFT control, (b) plyometric exercises + SJFT, (c) maximum strength + SJFT, and (d) contrast + SJFT. The following variables were quantified: throws performed during series A, B, and C; total number of throws; heart rate immediately and 1 minute after the test; and test index. Significant differences were found in the number of throws during series A: the plyometric exercise (6.4 ± 0.5 throws) was superior (p < 0.05) to the control condition (5.6 ± 0.5 throws). Heart rate 1 minute after the SJFT was higher (p < 0.01) during the plyometric exercise (192 ± 8 bpm) than during the contrast exercise (184 ± 9 bpm). The contrast exercise (13.58 ± 0.72) resulted in better index values than the control (14.67 ± 1.30) and plyometric exercises (14.51 ± 0.54). Thus, this study suggests that contrast and plyometric exercises performed before the SJFT can result in improvements in the test index and anaerobic power of judo athletes, respectively.

Fit-climbing Test: a Field Test for Indoor Rock Climbing

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Sep, 2011  |  Pubmed ID: 21904243

The aim of this study was to develop an indoor rock-climbing test on an artificial wall (Fitclimbing test). Thirteen climbers (elite group (EG) = 6; recreational group (RG) = 7) performed the following tests: 1) familiarization in the Fit-climbing test; 2) the Fit-climbing test, and 3) a retest to evaluate the Fit-climbing test's reliability. Gas exchange, blood lactate concentration, handgrip strength, and heart rate were measured during the test. Oxygen uptake during the Fit-climbing test was not different between groups (EG = 8.4 ± 1.1 L; RG = 7.9 ± 1.5 L, p > 0.05). EG performance (120 ± 7 movements) was statistically higher than RG climbers' performance (78 ± 13 movements) during theFit-climbing test. Consequently, the oxygen cost per movement during the Fit-climbing test of the EG was significantly higher than the RG (p < 0.05). Handgrip strength was higher in the EG when compared with the RG in both pre- and post- Fit-climbing test (p < 0.05). There were no significant differences in any other variables analysed during the Fit-climbing test (p > 0.05). Furthermore, the performance in the Fit-climbing test presented high reliability (intraclass correlation coefficient = 0.97). Therefore, the performance during the Fit-climbing test may be an alternative to evaluate rockclimbers because of its specificity and relation to oxygen cost per movement during climbing.

Reinterpreting the History of Women's Judo in Japan

The International Journal of the History of Sport. 2011  |  Pubmed ID: 21910277

This paper reassesses the role of women in judo in Japan, from its secluded and restricted beginnings in the late nineteenth century to the gradual changes in gender and social paradigms triggered by the influence of Western feminist struggle from the 1960s onwards. Judo has been considered in theory an inclusive martial art because its creator, Jigoro Kano, stressed safety, etiquette and moral teachings irrespective of age, size or gender of its adherents. However, the social and cultural environment in Japan has traditionally discriminated against women both outside and inside the dojo (training place). We treat this issue historically, considering the broader context of the Japanese social, political and cultural developments.

Energy System Contributions to the Special Judo Fitness Test

International Journal of Sports Physiology and Performance. Sep, 2011  |  Pubmed ID: 21911859

This study investigated the energy system contributions of judo athletes to the Special Judo Fitness Test (SJFT).

Tracking 10-year Competitive Winning Performance of Judo Athletes Across Age Groups

Perceptual and Motor Skills. Aug, 2011  |  Pubmed ID: 21987915

Little information is available concerning early specialization and competitive success in judo across the early training years. Thus, the present objective was to verify the stability of individual competitive performance of a state-level championship for judo athletes who had been previously successful. For this, 406 athletes from six age groups (9 to 20+ years old) of each sex were followed for 10 years. Using recorded data from the São Paulo State Judo Federation beginning in 1999, the scores and standings for these judo players were analyzed. The proportion of medal winners during this period was not constant, differing from the grand mean in all groups of both 204 males and 202 females. At the end of this period, only 7% of the male and 5% of the female athletes had maintained their competitive levels. Successful competitive performance in early judo competition was not associated with success later in adulthood.

Salivary Cortisol and Immunoglobulin A Responses to Simulated and Official Jiu-Jitsu Matches

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Oct, 2011  |  Pubmed ID: 22027851

The aim of the present study was to compare the salivary cortisol (sC) and the salivary immunoglobulin A (sIgA) responses to simulated and official Brazilian Jiu-Jitsu (BJJ) matches. Saliva samples were collected from nine male BJJ athletes before (pre) and after (post) two simulated (SM) and two official matches (OM) performed during two different competitions. Salivary cortisol, sIgA concentrations (absolute concentration of sIgA [sIgAabs] and the secretion rate of sIgA [sIgArate]) were measured by enzyme linked immunosorbent assay. For sC, there was an effect of condition (SM vs. OM) (p < 0.05) and a time effect (pre and post) (p < 0.05). sC was lower during SM as compared to OM and lower at pre-, when compared to, post-measurements. No changes were observed for sIgA measurements. In summary, both simulated and official BJJ matches can raise sC levels. Moreover, the higher sC resting levels, observed before OM, suggest that psychological factors associated with high physical-physiological demands from official BJJ competitions maximize stress hormone responses. In addition, the present findings suggest that the acute effect of BJJ matches on mucosal immunity is minimal and it seems unlikely that changes in cortisol play a major role in the alterations in sIgA levels in response to BJJ matches. The findings of the present study suggest that the use of sC can provide valuable information for coaches regarding athletes' responses to competition. In addition, psychological strategies should be implemented before events, to improve the manner by which BJJ athletes cope with the stress inherent to official matches.

Anthropometric, Physiological, Performance, and Nutritional Profile of the Brazil National Canoe Polo Team

Journal of Sports Sciences. 2012  |  Pubmed ID: 22168392

Abstract The purpose of this study was to determine the physiological, anthropometric, performance, and nutritional characteristics of the Brazil Canoe Polo National Team. Ten male canoe polo athletes (age 26.7 ± 4.1 years) performed a battery of tests including assessments of anthropometric parameters, upper-body anaerobic power (Wingate), muscular strength, aerobic power, and nutritional profile. In addition, we characterized heart rate and plasma lactate responses and the temporal pattern of the effort/recovery during a simulated canoe polo match. The main results are as follows: body fat, 12.3 ± 4.0%; upper-body peak and mean power, 6.8 ± 0.5 and 4.7 ± 0.4 W · kg(-1), respectively; 1-RM bench press, 99.1 ± 11.7 kg; peak oxygen uptake, 44.3 ± 5.8 mL · kg(-1) · min(-1); total energy intake, 42.8 ± 8.6 kcal · kg(-1); protein, carbohydrate, and fat intakes, 1.9 ± 0.1, 5.0 ± 1.5, and 1.7 ± 0.4 g · kg(-1), respectively; mean heart rate, 146 ± 11 beats · min(-1); plasma lactate, 5.7 ± 3.8 mmol · L(-1) at half-time and 4.6 ± 2.2 mmol · L(-1) at the end of the match; effort time (relative to total match time), 93.1 ± 3.0%; number of sprints, 9.6 ± 4.4. The results of this study will assist coaches, trainers, and nutritionists in developing more adequate training programmes and dietary interventions for canoe polo athletes.

Postactivation Potentiation: Effect of Various Recovery Intervals on Bench Press Power Performance

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Mar, 2012  |  Pubmed ID: 22297412

Ferreira, SLA, Panissa, VLG, Miarka, B, and Franchini, E. Postactivation potentiation: effect of various recovery intervals on bench press power performance. J Strength Cond Res 26(3): 739-744, 2012-Postactivation potentiation (PAP) is a strategy used to improve performance in power activities. The aim of this study was to determine if power during bench press exercise was increased when preceded by 1 repetition maximum (1RM) in the same exercise and to determine which time interval could optimize PAP response. For this, 11 healthy male subjects (age, 25 ± 4 years; height, 178 ± 6 cm; body mass, 74 ± 8 kg; bench press 1RM, 76 ± 19 kg) underwent 6 sessions. Two control sessions were conducted to determine both bench press 1RM and power (6 repetitions at 50% 1RM). The 4 experimental sessions were composed of a 1RM exercise followed by power sets with different recovery intervals (1, 3, 5, and 7 minutes), performed on different days, and determined randomly. Power values were measured via Peak Power equipment (Cefise, Nova Odessa, São Paulo, Brazil). The conditions were compared using an analysis of variance with repeated measures, followed by a Tukey test. The significance level was set at p < 0.05. There was a significant increase in PAP in concentric contractions after 7 minutes of recovery compared with the control and 1-minute recovery conditions (p < 0.05). Our results indicated that 7 minutes of recovery has generated an increase in PAP in bench press and that such a strategy could be applied as an interesting alternative to enhance the performance in tasks aimed at increasing upper-body power performance.

Reliability and Construct Validity of the Karate Specific Aerobic Test (KSAT)

Journal of Strength and Conditioning Research / National Strength & Conditioning Association. Feb, 2012  |  Pubmed ID: 22344054

The aim of this study was to examine absolute and relative reliability and external responsiveness of the Karate specific aerobic test (KSAT). This study comprised 43 male karatekas, 19 of them participated in the first study to establish test-retest reliability and 40, selected on the bases of their karate experience and level of practice, participated in the second study to identify external responsiveness of the KSAT. The latter group was divided into two categories: national level group (Gn) and regional level group (Gr). Analysis showed excellent test-retest reliability of time to exhaustion (TE), with intraclass correlation coefficient ICC(3,1) >0.90, standard error of measurement SEM <5%: (3.2%) and mean difference (bias) ± the 95% limits of agreement: -9.5±78.8 s. There was a significant difference between test-retest session in peak lactate concentration (Peak [La]) (9.12±2.59 mmol.l vs 8.05±2.67 mmol.l; p<0.05), but not in peak heart rate (HRpeak) and rating of perceived exertion (RPE) (196±9 bpm vs 194±9 bpm and 7.6±0.93 vs 7.8±1.15; p>0.05), respectively. National level karate athletes (1032±101-s) were better than regional level (841±134-s) on time to exhaustion (TE) performance during KSAT (p<0.001). Thus, KSAT provided good external responsiveness. The area under the receiver operator characteristics (ROC) curve was >0.70 (0.86; CI 95%: 0.72-0.95). Significant difference was detected on Peak [La] between national (6.09±1.78mmol.l) and regional level (8.48±2.63mmol.l) groups, but not in HRpeak (194±8 bpm vs 195±8 bpm) and RPE (7.57±1.15 vs 7.42±1.1) respectively. The result of this study indicates that KSAT provides excellent absolute and relative reliabilities. The KSAT can effectively distinguish karate athletes of different competitive levels. Thus, the KSAT may be suitable for field assessment of aerobic fitness of karate practitioners.

Methods of Body Mass Reduction by Combat Sports' Athletes

International Journal of Sport Nutrition and Exercise Metabolism. Feb, 2012  |  Pubmed ID: 22349031

The aim of this study was to investigate the methods adopted to reduce body mass (BM) in competitive athletes from the grappling (judo, jiu-jitsu) and striker (karate and taekwondo) combat sports' athletes in the State of Minas Gerais Brazil. An exploratory methodology was employed through descriptive research, using a standardized questionnaire with objective questions self-administered to 580 athletes (25.0±3.7 yrs, 74.5±9.7 kg and 16.4±5.1% of body fat). Regardless of the sport, 60% of the athletes reported using a method of rapid weight loss (RWL) through increased energy expenditure. Strikers tend to begin reducing BM during adolescence. Furthermore, 50% of the samples used saunas and plastic clothing, and only 26.1% received advice from a nutritionist. We conclude that a high percentage of athletes use RWL methods. In addition, a high percentage of athletes use unapproved or prohibited methods, such as diuretics, saunas and plastic clothing. The age at which combat sports' athletes reduce BM for the first time is also worry, especially among strikers.

Methods of Body-mass Reduction by Combat Sport Athletes

International Journal of Sport Nutrition and Exercise Metabolism. Apr, 2012  |  Pubmed ID: 22465869

The aim of this study was to investigate the methods adopted to reduce body mass (BM) in competitive athletes from the grappling (judo, jujitsu) and striking (karate and tae kwon do) combat sports in the state of Minas Gerais, Brazil. An exploratory methodology was employed through descriptive research, using a standardized questionnaire with objective questions self-administered to 580 athletes (25.0 ± 3.7 yr, 74.5 ± 9.7 kg, and 16.4% ± 5.1% body fat). Regardless of the sport, 60% of the athletes reported using a method of rapid weight loss (RWL) through increased energy expenditure. Strikers tend to begin reducing BM during adolescence. Furthermore, 50% of the sample used saunas and plastic clothing, and only 26.1% received advice from a nutritionist. The authors conclude that a high percentage of athletes uses RWL methods. In addition, a high percentage of athletes uses unapproved or prohibited methods such as diuretics, saunas, and plastic clothing. The age at which combat sport athletes reduce BM for the first time is also worrying, especially among strikers.

Energy Demands in Taekwondo Athletes During Combat Simulation

European Journal of Applied Physiology. Apr, 2012  |  Pubmed ID: 21769736

The purpose of this study was to investigate energy system contributions and energy costs in combat situations. The sample consisted of 10 male taekwondo athletes (age: 21 ± 6 years old; height: 176.2 ± 5.3 cm; body mass: 67.2 ± 8.9 kg) who compete at the national or international level. To estimate the energy contributions, and total energy cost of the fights, athletes performed a simulated competition consisting of three 2 min rounds with a 1 min recovery between each round. The combats were filmed to quantify the actual time spent fighting in each round. The contribution of the aerobic (W (AER)), anaerobic alactic (W (PCR)), and anaerobic lactic [Formula: see text] energy systems was estimated through the measurement of oxygen consumption during the activity, the fast component of excess post-exercise oxygen consumption, and the change in blood lactate concentration in each round, respectively. The mean ratio of high intensity actions to moments of low intensity (steps and pauses) was ~1:7. The W (AER), W (PCR) and [Formula: see text] system contributions were estimated as 120 ± 22 kJ (66 ± 6%), 54 ± 21 kJ (30 ± 6%), 8.5 kJ (4 ± 2%), respectively. Thus, training sessions should be directed mainly to the improvement of the anaerobic alactic system (responsible by the high-intensity actions), and of the aerobic system (responsible by the recovery process between high-intensity actions).

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