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1.
Eur J Sport Sci ; 23(5): 774-788, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35380916

RESUMEN

Previous research has explored the demands of amateur boxing-specific activity; however, no holistic review of the acute responses to such activity currently exists. This paper aimed to provide a systematic review of the available literature on the acute physiological, endocrine, biochemical, and performance responses to amateur boxing-specific activity. Following a search of EBSCOhost, SPORTDiscus, PubMed and Google Scholar databases, 25 studies were identified as meeting the inclusion criteria for the review. The methodological quality of the included studies was assessed via a modified Downs and Black checklist. Random-effects meta-analysis of standardised mean differences (SMD) revealed large (SMD = 4.62) increases in pre-post blood lactate (BLa), cortisol (SMD = 1.33), myoglobin (Mb) (SMD = 1.43), aspartate transaminase (AST) (SMD = 1.37), and alanine aminotransferase (ALT) (SMD = 0.97), in addition to moderate increases in creatine kinase (CK) (SMD = 0.65). Small pre-post increases in counter-movement jump (CMJ) height (SMD = 0.33) were observed. Consistently greater pre-post alterations were observed in competitive bouts, followed by sparring, and less so in boxing-specific simulations. Considerable physiological, endocrine, and biochemical responses are elicited following amateur boxing. Interestingly, neuromuscular and task-specific performance may not deteriorate following boxing-specific activity. The findings of the review may assist in the designing and periodising of boxing-specific training, dependent on the desired physical adaptations, training phase, and recovery status of the amateur boxer.HighlightsAmateur boxing elicits a considerable acute physiological, hormonal, and biochemical response.Such responses are typically greater in competitive bouts, followed by sparring, and less so in simulated activity.The considerable demands of amateur boxing-specific activity do not appear to negatively affect neuromuscular or task-specific performance.Amateur boxers may be conditioned to preserve performance despite the acute demands of the sport, or the lack of performance decrement may reflect the short duration of amateur boxing.


Asunto(s)
Boxeo , Humanos , Boxeo/fisiología , Atletas , Examen Físico , Movimiento/fisiología , Análisis y Desempeño de Tareas
2.
Int J Sports Physiol Perform ; 17(11): 1621-1633, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36167315

RESUMEN

PURPOSE: The purpose of this study was to assess the efficacy of upper-body punch-specific isometric (ISO) and elastic resistance (ER) conditioning activities (CAs) on the punch force and neuromuscular performance of amateur boxers. METHODS: Ten male senior elite amateur boxers (19.7 [1.2]| y; height 180.9 [7.0] cm; mass 78.7 [9.6] kg) visited the laboratory on 4 separate occasions. Initially, the participants performed baseline physical tests comprising bench-press 1-repetition maximum and countermovement jumps. On the other 3 occasions, the boxers performed maximal punches against a vertically mounted force plate and maximal countermovement jumps prior to and following an ISO or ER CA, as well as a control trial. RESULTS: No interactions between CA × time were found in all performance variables. As observed by mean changes, effect sizes, and signal:noise ratio, both the ISO and ER, but not the control trial, consistently produced small to moderate, worthwhile increases in punch force and rate of force development, with the greatest increases in performance typically observed in the ISO trial. No meaningful improvements were observed in countermovement jump performance in all trials, indicative of a localized postactivation performance enhancement effect. CONCLUSION: In conclusion, the ISO and ER CAs may be implemented in an amateur boxers' warm-up to acutely enhance punch-force variables, although the ISO punch appears to be the superior CA to improve punch-specific performance. The CAs used in the present study may also be relevant to other combat sports inclusive of a striking element.


Asunto(s)
Boxeo , Deportes , Ejercicio de Calentamiento , Humanos , Masculino , Boxeo/fisiología , Adulto Joven
3.
PLoS One ; 17(3): e0264910, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35294451

RESUMEN

The present study aimed to propose a new multidimensional taekwondo-specific test to estimate aerobic power, anaerobic fitness, and agility. Out of sixty-five male volunteers, forty-six, forty-eight, and fifty athletes (18-35 years; black- and red-belt level) were included in the final analysis for aerobic, anaerobic, and agility assessments, respectively. Maximum oxygen uptake (VO2max, using a graded exercise test on a treadmill), anaerobic power (using the 30-s Wingate anaerobic test, WAnT), and agility performance (using the agility T-Test) were measured via non-specific laboratory and field tests across a two-week period. The taekwondo-specific aerobic-anaerobic-agility (TAAA) test comprised six 20-s intervals of shuttle sprints over a 4-m distance, and the execution of roundhouse kicks alternating the legs at the end of each distance, with 10-s rest intervals between the sets. The multiple linear regression revealed that the difference between heart rate (HR) after and 1 minute after the TAAA test (p < 0.001), and body mass index (BMI; p = 0.006) were significant to estimate VO2max. Likewise, there was a very large (R = 0.79) and large (R = 0.55) correlation between the average and maximum number of kicks performed in the TAAA test and the WAnT mean and peak power, respectively (p < 0.001). Moreover, a linear relationship was found between the T-Test and agility performance acquired in the TAAA test (R = 0.74; p < 0.001). The TAAA test can be considered a valid simple tool for monitoring VO2max, anaerobic fitness, and agility in male taekwondo athletes.


Asunto(s)
Rendimiento Atlético , Artes Marciales , Anaerobiosis , Rendimiento Atlético/fisiología , Prueba de Esfuerzo/métodos , Humanos , Masculino , Artes Marciales/fisiología , Oxígeno , Consumo de Oxígeno/fisiología
4.
Eur J Appl Physiol ; 121(12): 3283-3295, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34417881

RESUMEN

As a nitric oxide (NO) enhancer, citrulline malate (CM) has recently been touted as a potential ergogenic aid to both resistance and high-intensity exercise performance, as well as the recovery of muscular performance. The mechanism has been associated with enhanced blood flow to active musculature, however, it might be more far-reaching as either ammonia homeostasis could be improved, or ATP production could be increased via greater availability of malate. Moreover, CM might improve muscle recovery via increased nutrient delivery and/or removal of waste products. To date, a single acute 8 g dose of CM on either resistance exercise performance or cycling has been the most common approach, which has produced equivocal results. This makes the effectiveness of CM to improve exercise performance difficult to determine. Reasons for the disparity in conclusions seem to be due to methodological discrepancies such as the testing protocols and the associated test-retest reliability, dosing strategy (i.e., amount and timing), and the recent discovery of quality control issues with some manufacturers stated (i.e., citrulline:malate ratios). Further exploration of the optimal dose is therefore required including quantification of the bioavailability of NO, citrulline, and malate following ingestion of a range of CM doses. Similarly, further well-controlled studies using highly repeatable exercise protocols with a large aerobic component are required to assess the mechanisms associated with this supplement appropriately. Until such studies are completed, the efficacy of CM supplementation to improve exercise performance remains ambiguous.


Asunto(s)
Rendimiento Atlético , Citrulina/análogos & derivados , Malatos/farmacología , Sustancias para Mejorar el Rendimiento/farmacología , Citrulina/farmacología , Suplementos Dietéticos , Humanos
5.
J Strength Cond Res ; 32(9): 2529-2541, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29781933

RESUMEN

Bridge, CA, Sparks, SA, McNaughton, LR, Close, GL, Hausen, M, Gurgel, J, and Drust, B. Repeated exposure to taekwondo combat modulates the physiological and hormonal responses to subsequent bouts and recovery periods. J Strength Cond Res 32(9): 2529-2541, 2018-This study examined the physiological and hormonal responses to successive taekwondo combats using an ecologically valid competition time structure. Ten elite male international taekwondo competitors (age 19 ± 3 years) took part in a simulated championship event. The competitors performed 4 combats that were interspersed with different recovery intervals (63 ± 4, 31 ± 3 and 156 ± 5 minutes, respectively). Heart rate (HR) was measured during the combats and venous blood samples were obtained both before and after each combat to determine the plasma metabolite and hormone concentrations. The plasma noradrenaline (21.8 ± 12.8 vs. 15.0 ± 7.0 nmol·l) and lactate (13.9 ± 4.2 vs. 10.5 ± 3.2 mmol·l) responses were attenuated (p < 0.05) between combat 1 and 4. Higher (p < 0.05) HR responses were evident in the final combat when compared with the earlier combats. Higher (p < 0.05) resting HR (139 ± 10 vs. 127 ± 12 b·min), plasma lactate (3.1 ± 1.2 vs. 2.0 ± 0.7 mmol·l), glycerol (131 ± 83 vs. 56 ± 38 µmol·l) and nonesterified free fatty acid (0.95 ± 0.29 vs. 0.71 ± 0.28 mmol·l) concentrations were measured before combat 3 compared with combat 1. Repeated exposure to taekwondo combat using an ecologically valid time structure modulates the physiological and hormonal responses to subsequent bouts and recovery periods. Strategies designed to assist competitors to effectively manage the metabolic changes associated with the fight schedule and promote recovery between the bouts may be important during championship events.


Asunto(s)
Artes Marciales/fisiología , Adolescente , Adulto , Biomarcadores/sangre , Frecuencia Cardíaca/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Norepinefrina/sangre , Adulto Joven
6.
Front Physiol ; 7: 536, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27891098

RESUMEN

Little is currently known regarding competitor influence on pacing at the start of an event and in particular the subsequent effect on the remaining distance. The purpose of the present study was to investigate the influence of starting pace on the physiological and psychological responses during cycling time trials (TT) utilizing an innovative approach allowing pace to be accurately and dynamically replicated, as well as deceptively manipulated. Ten competitive male cyclists completed five 16.1 km TT, two baseline trials performed alone (BLs), and three with a simulated, dynamic avatar of which they were to match the pace of for the initial 4 km. The avatar represented either the cyclist's fastest BL performance (NORM), 105% (FAST), or 95% (SLOW), of fastest BL performance (FBL). Physiological and psychological responses were measured every quartile of the TT. Despite manipulating a starting speed of ± 5% of fastest previous performance, there was no effect on overall 16.1 km TT performance. Manipulated starting strategies did however evoke different physiological and perceptual responses. Whole trial differences found that SLOW produced lower HR, VO2, BLa and RPE than FBL (p ≤ 0.03) and higher SE than FAST (p ≤ 0.03). Additionally, FAST had greater internal attention than NORM (p < 0.04). Over time all psychological and physiological variables had a significant condition × quartile interaction in the initial or second quartile mediated by the prescribed starting strategies. Furthermore, RPE, affect, and internal attention remained elevated throughout FAST despite an attenuation in pace during self-selection of pace. There were no differences in performance time when manipulating a 16.1 km cycling TT starting strategy. A slow start, encouraged greater positive perceptions, and less negative physiological consequences than a faster start, and produces no impairment to performance time. It would therefore be considered an advantage in a non-drafting event, not to follow pace of fellow, superior competitors at the start of an event but perform a more negative pacing strategy, with the potential for a greater speed increase against opponents in the latter stages.

7.
Front Physiol ; 7: 399, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27713701

RESUMEN

The provision of performance-related feedback during exercise is acknowledged as an influential external cue used to inform pacing decisions. The provision of this feedback in a challenging or deceptive context allows research to explore how feedback can be used to improve performance and influence perceptual responses. However, the effects of deception on both acute and residual responses have yet to be explored, despite potential application for performance enhancement. Therefore, this study investigated the effects of challenging and deceptive feedback on perceptual responses and performance in self-paced cycling time trials (TT) and explored whether changes in performance are sustained in a subsequent TT following the disclosure of the deception. Seventeen trained male cyclists were assigned to either an accurate or deceptive feedback group and performed four 16.1 km cycling TTs; (1 and 2) ride-alone baseline TTs where a fastest baseline (FBL) performance was identified, (3) a TT against a virtual avatar representing 102% of their FBL performance (PACER), and (4) a subsequent ride-alone TT (SUB). The deception group, however, were initially informed that the avatar accurately represented their FBL, but prior to SUB were correctly informed of the nature of the avatar. Affect, self-efficacy and RPE were measured every quartile. Both groups performed PACER faster than FBL and SUB (p < 0.05) and experienced lower affect (p = 0.016), lower self-efficacy (p = 0.011), and higher RPE (p < 0.001) in PACER than FBL. No significant differences were found between FBL and SUB for any variable. The presence of the pacer rather than the manipulation of performance beliefs acutely facilitates TT performance and perceptual responses. Revealing that athletes' performance beliefs were falsely negative due to deceptive feedback provision has no effect on subsequent perceptions or performance. A single experiential exposure may not be sufficient to produce meaningful changes in the performance beliefs of trained individuals beyond the acute setting.

8.
Amino Acids ; 48(11): 2581-2587, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27380030

RESUMEN

Taurine (TAU) has been shown to improve exercise time to exhaustion and 3-km running performance; however, no studies have considered the effect of acute TAU ingestion on short duration cycling time trial (TT) performance. The aim of this study was to determine the effects of a single oral acute dose of 1000 mg of TAU on a laboratory simulated 4-km cycling TT. Eleven trained male cyclists performed three, 4-km TTs. The first of the trials was a familiarisation, followed by two subsequent trials which were performed two hours after the consumption of either 1000 mg of TAU or placebo (P), using a double-blind randomised crossover design. Capillary blood samples were obtained prior to the start and immediately after each TT for the measurement of lactate, pH and HCO3-. There was no effect of TAU (p = 0.731, d = 0.151) on performance (390 ± 27 and 388 ± 21 s for TAU and P, respectively), nor were there any condition main effects for VO2, lactate, pH, or HCO3- (p > 0.05) despite post TT changes in lactate (7.3 ± 2.5 mmol l-1, p < 0.001, d = 2.86, 7.6 ± 2.0 mmol l-1 p < 0.001, d = 3.75); pH (-0.255 ± 0.1, p < 0.001, d = 2.62, -0.258 ± 0.09, p < 0.001, d = 2.87); HCO3- (-13.58 ± 2.7 mmol l-1, p < 0.001, d = 5.04 vs. -13.36 ± 2.3, p < 0.001, d = 5.72 for TAU and P, respectively). The findings of this study suggest that a pre-exercise dose of 1000 mg TAU offers no performance advantage during 4-km TT nor does it alter the blood buffering responses in trained cyclists.


Asunto(s)
Ciclismo , Resistencia Física/efectos de los fármacos , Taurina/administración & dosificación , Adulto , Método Doble Ciego , Humanos , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad
9.
J Strength Cond Res ; 30(2): 561-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26815179

RESUMEN

This work examined the influence of an acute dose of sodium bicarbonate (NaHCO3) on buffering capacity and performance during a repeated sprint ability (RSA) protocol. Eleven (mean ± SD: age 24.6 ± 6.1 years; mass 74.9 ± 5.7 kg; height 177.2 ± 6.7 cm) participated in the study, undertaking 4 test sessions. On the first visit to the laboratory, each participant ingested 300 mg · kg(-1) of NaHCO3 (in 450 ml of flavored water) and blood samples were obtained at regular intervals to determine the individual times peak pH and HCO3. In subsequent visits, participants ingested 300 mg · kg(-1) of NaHCO3, 270 mg · kg(-1) body mass (BM) of NaCI, or no drink followed by a RSA cycling protocol (10 × 6 seconds sprints with 60 seconds recovery), which commenced at each individuals predetermined ingestion peak pH response time. Blood samples were obtained before exercise and after the first, fifth, and 10th sprint to determine the blood pH, HCO3, and lactate (La) responses. Total work completed during the repeated sprint protocol was higher (p ≤ 0.05) in the NaHCO3 condition (69.8 ± 11.7 kJ) compared with both the control (59.6 ± 12.2 kJ) and placebo (63.0 ± 8.3 kJ) conditions. Peak power output was similar (p > 0.05) between the 3 conditions. Relative to the control and placebo conditions, NaHCO3 ingestion induced higher (p ≤ 0.05) blood pH and HCO3 concentrations before exercise and during the bouts, and higher lactate concentrations (p ≤ 0.05) after the final sprint. Results suggest that NaHCO3 improves the total amount of work completed during RSA through enhanced buffering capacity.


Asunto(s)
Rendimiento Atlético/fisiología , Ciclismo/fisiología , Sustancias para Mejorar el Rendimiento/farmacología , Bicarbonato de Sodio/farmacología , Adulto , Biomarcadores/sangre , Tampones (Química) , Estudios Cruzados , Método Doble Ciego , Prueba de Esfuerzo , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Ácido Láctico/sangre , Masculino , Sustancias para Mejorar el Rendimiento/administración & dosificación , Bicarbonato de Sodio/administración & dosificación , Adulto Joven
10.
J Sci Med Sport ; 19(9): 771-6, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26726003

RESUMEN

OBJECTIVES: Feedback deception is used to explore the importance of expectations on pacing strategy and performance in self-paced exercise. The deception of feedback from a previous performance explores the importance of experience knowledge on exercise behaviour. This study aimed to explore the acute and residual effects of the deception of previous performance speed on perceptual responses and performance in cycling time trials. DESIGN: A parallel-group design. METHODS: Twenty cyclists were assigned to a control or deception group and performed 16.1km time trials. Following a ride-alone baseline time trial (FBL), participants performed against a virtual avatar representing their FBL performance (PACER), then completed a subsequent ride-alone time trial (SUB). The avatar in the deception group, however, was unknowingly set 2% faster than their FBL. RESULTS: Both groups performed faster in PACER than FBL and SUB (p<0.05), but SUB was not significantly different to FBL. Affect was more negative and Ratings of Perceived Exertion (RPE) were higher in PACER than FBL in the deception group (p<0.05). CONCLUSIONS: The presence of a visual pacer acutely facilitated time trial performance, but deceptive feedback had no additional effect on performance. The deception group, however, experienced more negative affect and higher RPE in PACER, whereas these responses were absent in the control group. The performance improvement was not sustained in SUB, suggesting no residual performance effects occurred.


Asunto(s)
Rendimiento Atlético/fisiología , Ciclismo/fisiología , Decepción , Ejercicio Físico/fisiología , Adulto , Rendimiento Atlético/psicología , Ciclismo/psicología , Fenómenos Biomecánicos , Estudios de Casos y Controles , Ejercicio Físico/psicología , Retroalimentación , Humanos , Modelos Lineales , Masculino , Percepción , Autoeficacia , Factores de Tiempo
11.
Med Sci Sports Exerc ; 47(11): 2423-30, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25970660

RESUMEN

PURPOSE: Deceptive manipulations of performance intensity have previously been investigated in cycling time trials (TT) but used different magnitudes, methods, and task durations. This study examines previously used magnitudes of deception during 16.1-km TT and explores yet unexamined psychological responses. METHODS: Twelve trained cyclists completed five TT, performing two baseline trials alone, one against a simulated dynamic avatar representing 102% of fastest baseline trial (TT(102%)), one against a 105% avatar (TT(105%)), and one against both avatars (TT(102%,105%)). RESULTS: Deceptive use of competitors to disguise intensity manipulation enabled accomplishment of performance improvements greater than their perceived maximal (1.3%-1.7%). Despite a similar improvement in performance, during TT(102%,105%), there was significantly lower affect and self-efficacy to continue pace than those during TT(105%) (P < 0.05), significantly lower self-efficacy to compete than that during TT(102%) (P = 0.004), and greater RPE than that during TTFBL (P < 0.001). CONCLUSIONS: Because the interpretation of performance information and perceptions depends on the manner in which it is presented, i.e., "framing effect," it could be suggested that the summative effect of two opponents could have evoked negative perceptions despite eliciting a similar performance. Magnitudes of deception produce similar performance enhancement yet elicit diverse psychological responses mediated by the external competitive environment the participants were performing in.


Asunto(s)
Ciclismo/fisiología , Ciclismo/psicología , Decepción , Percepción/fisiología , Esfuerzo Físico/fisiología , Adulto , Retroalimentación Fisiológica , Humanos , Masculino , Autoeficacia
12.
Med Sci Sports Exerc ; 47(4): 825-32, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25121516

RESUMEN

UNLABELLED: The psychological construct of affect is proposed to significantly contribute to pacing decisions during exercise. Borg's RPE scale, another important regulator of work rate, is criticized as an inadequate measure of the multiple perceptual responses experienced. This study aimed to examine power output distribution and associated changes in affect, self-efficacy, perceptual cues, HR, and respiratory gases during both 16.1- and 40-km self-paced cycling time trials (TT). Secondly, the differentiation between physical perceptions of exertion and sense of effort in self-paced exercise was investigated. METHOD: Fifteen trained male cyclists completed 16.1- and 40-km TT using a CompuTrainer cycle ergometer. Time, power output distribution, affect, self-efficacy, physical RPE (P-RPE), task effort and awareness (TEA), HR, and respiratory gases were measured throughout each TT. Linear mixed models explored associations of these variables with power output distribution and the relationship between P-RPE and TEA. RESULTS: Similar pacing strategies were adopted in the 16.1- and 40-km TT (P = 0.31), and the main effects were found for affect (P = 0.001) and RER (P < 0.001). Interactions between affect (P = 0.037) and RER (P = 0.004), with condition, indicated closer associations with power output distribution in 16.1 km than that in 40 km TT. P-RPE was not significantly different from TEA (P = 0.053). CONCLUSION: A significant association between affect and power output distribution suggests that affective responses are task dependent even in self-paced exercise, and a greater association is demonstrated in higher intensity, 16.1 km TT. Furthermore, physical perceptions of exertion are not clearly differentiated from the sense of effort in self-paced exercise.


Asunto(s)
Afecto/fisiología , Ciclismo/fisiología , Ciclismo/psicología , Percepción , Esfuerzo Físico/fisiología , Adulto , Señales (Psicología) , Frecuencia Cardíaca , Humanos , Masculino , Estudios Prospectivos , Intercambio Gaseoso Pulmonar , Autoeficacia
13.
Int J Sports Physiol Perform ; 10(1): 39-45, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24896154

RESUMEN

UNLABELLED: Power meters have traditionally been integrated into the crank set, but several manufacturers have designed new systems located elsewhere on the bike, such as inside the pedals. PURPOSE: This study aimed to determine the validity and reliability of the Keo power pedals during several laboratory cycling tasks. METHODS: Ten active male participants (mean ± SD age 34.0 ± 10.6 y, height 1.77 ± 0.04 m, body mass 76.5 ± 10.7 kg) familiar with laboratory cycling protocols completed this study. Each participant was required to complete 2 laboratory cycling trials on an SRM ergometer (SRM, Germany) that was also fitted with the Keo power pedals (Look, France). The trials consisted of an incremental test to exhaustion followed by 10 min rest and then three 10-s sprint tests separated by 3 min of cycling at 100 W. RESULTS: Over power ranges of 75 to 1147 W, the Keo power-pedal system produced typical error values of 0.40, 0.21, and 0.21 for the incremental, sprint, and combined trials, respectively, compared with the SRM. Mean differences of 21.0 and 18.6 W were observed between trials 1 and 2 with the Keo system in the incremental and combined protocols, respectively. In contrast, the SRM produced differences of 1.3 and 0.6 W for the same protocols. CONCLUSIONS: The power data from the Keo power pedals should be treated with some caution given the presence of mean differences between them and the SRM. Furthermore, this is exacerbated by poorer reliability than that of the SRM power meter.


Asunto(s)
Ciclismo/fisiología , Prueba de Esfuerzo/instrumentación , Adulto , Análisis Costo-Beneficio , Diseño de Equipo/economía , Prueba de Esfuerzo/economía , Humanos , Masculino , Fuerza Muscular/fisiología , Reproducibilidad de los Resultados , Adulto Joven
14.
Sports Med ; 44(6): 713-33, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24549477

RESUMEN

Taekwondo has evolved into a modern-day Olympic combat sport. The physical and physiological demands of modern-day taekwondo competition require athletes to be competent in several aspects of fitness. This review critically explores the physical and physiological characteristics of taekwondo athletes and presents implications for training and research. International taekwondo athletes possess low levels of body fat and a somatotype that characterises a blend of moderate musculoskeletal tissue and relative body linearity. While there is some variation in the maximum oxygen uptake of taekwondo athletes, moderate to high levels of cardio-respiratory fitness are necessary to support the metabolic demands of fighting and to facilitate recovery between consecutive matches. Taekwondo athletes demonstrate high peak anaerobic power characteristics of the lower limbs and this attribute appears to be conducive to achieving success in international competition. The ability to generate and sustain power output using both concentric and 'stretch-shortening cycle' muscle actions of the lower limbs may be important to support the technical and tactical actions in combat. Taekwondo competitors also display moderate to high maximum dynamic strength characteristics of the lower and upper extremities, and moderate endurance properties of the trunk and hip flexor musculature. The dynamic nature of the technical and tactical actions in the sport demand high flexibility of the lower limbs. More extensive research is required into the physical and physiological characteristics of taekwondo athletes to extend existing knowledge and to permit specialised conditioning for different populations within the sport.


Asunto(s)
Artes Marciales/fisiología , Aptitud Física/fisiología , Composición Corporal , Humanos , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Somatotipos
15.
Sports Med ; 43(12): 1243-57, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24002790

RESUMEN

The aim of an optimal pacing strategy during exercise is to enhance performance whilst ensuring physiological limits are not surpassed, which has been shown to result in a metabolic reserve at the end of the exercise. There has been debate surrounding the theoretical models that have been proposed to explain how pace is regulated, with more recent research investigating a central control of exercise regulation. Deception has recently emerged as a common, practical approach to manipulate key variables during exercise. There are a number of ways in which deception interventions have been designed, each intending to gain particular insights into pacing behaviour and performance. Deception methodologies can be conceptualised according to a number of dimensions such as deception timing (prior to or during exercise), presentation frequency (blind, discontinuous or continuous) and type of deception (performance, biofeedback or environmental feedback). However, research evidence on the effects of deception has been perplexing and the use of complex designs and varied methodologies makes it difficult to draw any definitive conclusions about how pacing strategy and performance are affected by deception. This review examines existing research in the area of deception and pacing strategies, and provides a critical appraisal of the different methodological approaches used to date. It is hoped that this analysis will inform the direction and methodology of future investigations in this area by addressing the mechanisms through which deception impacts upon performance and by elucidating the potential application of deception techniques in training and competitive settings.


Asunto(s)
Rendimiento Atlético/fisiología , Decepción , Ejercicio Físico/fisiología , Fatiga/fisiopatología , Deportes/fisiología , Metabolismo Energético , Humanos
16.
Int J Sports Physiol Perform ; 6(3): 344-57, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21911860

RESUMEN

PURPOSE: To examine the activity profiles of elite male competitors during international Taekwondo competition in relation to fin, feather, and heavy weight categories. METHODS: Twelve male Taekwondo competitors equally representing fin, feather, and heavy weight divisions were studied during the 2005 World Taekwondo Championships using a time-motion system developed to analyze the activities and activity phases. The frequency and duration of activities were recorded and assimilated into four independent activity phases: fighting activity, preparatory activity, nonpreparatory activity and stoppage activity. The total number of exchanges and kicks were also calculated for each combat. RESULTS: For all weight groupings the mean ± SD fighting time was 1.7 ± 0.3 s, preparatory time 6.4 ± 2.1 s, nonpreparatory time 3.0 ± 0.6 s, referee stoppage time 2.8 ± 0.9 s and 28 ± 6 exchanges and 31 ± 7 kicks were performed. Differences in the mean fighting time (fin: 1.4 ± 0.2 s vs heavy: 1.8 ± 0.3 s; P = .03; effect size [ES] = 1.57), preparatory time (fin: 5.3 ± 1.0 s vs feather: 8.2 ± 2.6 s; P = .03; ES = 1.47) and the total number of exchanges (feather: 24 ± 6 vs heavy: 32 ± 5; P = .03; ES = 1.44) were identified between the weight categories. CONCLUSIONS: The activity profile in international Taekwondo competition was modulated by competitors' weight category. These findings suggest that conditioning sessions may need to be specialized to the requirements of specific weight categories.


Asunto(s)
Rendimiento Atlético , Peso Corporal , Artes Marciales , Actividad Motora , Análisis de Varianza , Fenómenos Biomecánicos , Humanos , Masculino , Factores de Tiempo , Estudios de Tiempo y Movimiento
17.
Int J Sports Physiol Perform ; 4(4): 485-93, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20029099

RESUMEN

PURPOSE: To investigate the physiological responses and perceived exertion during international Taekwondo competition. METHODS: Eight male Taekwondo black belts (mean +/- SD, age 22 +/- 4 y, body mass 69.4 +/- 13.4 kg, height 1.82 +/- 0.10 m, competition experience 9 +/- 5 y) took part in an international-level Taekwondo competition. Each combat included three 2-min rounds with 30 s of recovery between each round. Heart rate (HR) was recorded at 5-s intervals during each combat. Capillary blood lactate samples were taken from the fingertip 1 min before competition, directly after each round and 1 min after competition. Competitors' rating of perceived exertion (RPE) was recorded for each round using Borg's 6-to-20 scale. RESULTS: HR (round 1: 175 +/- 15 to round 3: 187 +/- 8 beats x min(-1); P < .05), percentage of HR maximum (round 1: 89 +/- 8 to round 3: 96 +/- 5% HRmax; P < .05), blood lactate (round 1: 7.5 +/- 1.6 to round 3: 11.9 +/- 2.1 mmol x L(-1); P < .05) and RPE (round 1: 11 +/- 2 to round 3: 14 +/- 2; P < .05; mean +/- SD) increased significantly across rounds. CONCLUSIONS: International-level Taekwondo competition elicited near-maximal cardiovascular responses, high blood lactate concentrations, and increases in competitors' RPE across combat. Training should therefore include exercise bouts that sufficiently stimulate both aerobic and anaerobic metabolism.


Asunto(s)
Artes Marciales/fisiología , Esfuerzo Físico/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Adulto Joven
18.
J Strength Cond Res ; 21(3): 718-23, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17685682

RESUMEN

The purpose of this study was to evaluate the heart rate (HR) responses of specific Taekwondo training activities, practiced by experienced practitioners in a natural training environment. Eight male experienced Taekwondo practitioners, with 3- 13 years (5.4 +/- 3.2 years) experience took part in a 5-day Taekwondo training camp. Continuous HR measures were recorded at 5-second intervals during 6 training sessions; each session was observed and notated, and a diary of training activities was recorded. The HR responses were assimilated into 8 fundamental training activities for analysis: elastics, technical combinations, step sparring, pad work, forms, basic techniques and forms, sparring drills, and free sparring. Taekwondo training elicited HR into 64.7-81.4% of HR maximum (%HRmax). Moderate relative exercise intensities (64.7-69.4%HRmax) were elicited by elastics, technical combinations, and step sparring. The remaining 5 training activities elicited hard relative exercise intensities (74.7-81.4%HRmax). One-way repeated-measures analysis of variance with post hoc analysis revealed that elastics, technical combinations, and step sparring elicited significantly lower relative intensities than the remaining training activities (p < 0.05). Furthermore, forms, basic techniques and forms, sparring drills, and free sparring elicited significantly higher relative intensities than the remaining training activities (p < 0.05). In conclusion, all Taekwondo training activities in this study seemed suitable for cardiovascular conditioning, although different training activities stressed the cardiovascular system to different degrees. Practically, this suggests coaches need to structure Taekwondo training sessions based not only on the technical and tactical needs of practitioners but also in a manner that enables sufficient cardiovascular conditioning for competition.


Asunto(s)
Frecuencia Cardíaca/fisiología , Artes Marciales/fisiología , Educación y Entrenamiento Físico , Adulto , Análisis de Varianza , Humanos , Masculino , Aptitud Física/fisiología
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