Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 149
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Eur J Appl Physiol ; 124(2): 595-606, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37656280

RESUMO

PURPOSE: The physiological examination of boxing has been limited to systemic response in amateur athletes. The demands of professional boxing have been overlooked, despite the different competition format. We sought to determine the physiological demands placed on skeletal muscle in professional boxing. METHODS: Ten male professional boxers (age 26 ± 5 years, height 177 ± 4 cm, weight 71 ± 6 kg) were recruited for this observational study. On different days, the athletes completed 6 × 3 min rounds of pad, bag or spar-based training with 1 min recovery between each round. Prior to each session, participants put on a heart rate monitor and near-infrared spectroscopy attached to the belly of the rectus femoris muscle to record heart rate and muscle oxygenation. RESULTS: There were significantly less punches thrown in sparring compared to other training modalities (p < 0.001). Skeletal muscle oxygenation across training modalities consisted of a delay, fast desaturation and steady state. Across rounds there was a significant increase in time delay for desaturation (p = 0.016), rate of fast desaturation (p < 0.001) and duration of fast desaturation (p = 0.019). There was a significant difference in sparring for the heart rate where skeletal muscle oxygenation changes occurred compared to pads or bag sessions (p < 0.001). CONCLUSION: The findings highlight differences in the skeletal muscle response to the different training modalities. Practitioners need to be aware of the muscular demands of each session to allow optimal adaptation across a training camp. Training needs to allow the skeletal muscle to achieve a new oxygenation steady state rapidly to promote efficient performance across rounds.


Assuntos
Boxe , Humanos , Masculino , Adulto Jovem , Adulto , Boxe/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Fenômenos Fisiológicos Respiratórios , Músculo Esquelético , Músculo Quadríceps
2.
J Integr Neurosci ; 23(5): 102, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38812391

RESUMO

BACKGROUND: Repetitive mild traumatic brain injury (rmTBI) often occurs in individuals engaged in contact sports, particularly boxing. This study aimed to elucidate the effects of rmTBI on phase-locking value (PLV)-based graph theory and functional network architecture in individuals with boxing-related injuries in five frequency bands by employing resting-state electroencephalography (EEG). METHODS: Twenty-fore professional boxers and 25 matched healthy controls were recruited to perform a resting-state task, and their noninvasive scalp EEG data were collected simultaneously. Based on the construction of PLV matrices for boxers and controls, phase synchronization and graph-theoretic characteristics were identified in each frequency band. The significance of the calculated functional brain networks between the two populations was analyzed using a network-based statistical (NBS) approach. RESULTS: Compared to controls, boxers exhibited an increasing trend in PLV synchronization and notable differences in the distribution of functional centers, especially in the gamma frequency band. Additionally, attenuated nodal network parameters and decreased small-world measures were observed in the theta, beta, and gamma bands, suggesting that the functional network efficiency and small-world characteristics were significantly weakened in boxers. NBS analysis revealed that boxers exhibited a significant increase in network connectivity strength compared to controls in the theta, beta, and gamma frequency bands. The functional connectivity of the significance subnetworks exhibited an asymmetric distribution between the bilateral hemispheres, indicating that the optimized organization of information integration and segregation for the resting-state networks was imbalanced and disarranged for boxers. CONCLUSIONS: This is the first study to investigate the underlying deficits in PLV-based graph-theoretic characteristics and NBS-based functional networks in patients with rmTBI from the perspective of whole-brain resting-state EEG. Joint analyses of distinctive graph-theoretic representations and asymmetrically hyperconnected subnetworks in specific frequency bands may serve as an effective method to assess the underlying deficiencies in resting-state network processing in patients with sports-related rmTBI.


Assuntos
Boxe , Concussão Encefálica , Eletroencefalografia , Rede Nervosa , Humanos , Masculino , Adulto , Adulto Jovem , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Concussão Encefálica/fisiopatologia , Boxe/fisiologia , Ondas Encefálicas/fisiologia , Feminino , Encéfalo/fisiopatologia
3.
J Strength Cond Res ; 38(5): 948-950, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38662886

RESUMO

ABSTRACT: Peveler, WW, Schoffstall, J, Coots, J, Kilian, J, and Glauser, J. The effects of boxing glove design on thumb position when making a fist for striking. J Strength Cond Res 38(5): 948-950, 2024-It has been suggested that boxing glove design alters thumb position increasing the risk of injury. The purpose of this study was to determine the effects of boxing glove design on thumb joint angles when making a fist. Ten experienced fighters participated in this study. A DEXA scan was used to produce an x-ray image of thumb position for all conditions (no gloves and 10-oz boxing gloves). Mean values for dependent measures were compared using a paired-sample T test and an alpha of 0.05. The carpometacarpal (CMC) joint angle was significantly different between no glove (14.1 ± 6.54°) and boxing glove (34.2 ± 7.60°) at p ≤ 0.001. The metacarpophalangeal (MP) joint angle was significantly different between no glove (132.6 ± 12.74°) and boxing glove (149.40 ± 8.15°) at p ≤ 0.001. The IP joint angle was not significantly different between no glove (135.50 ± 19.12°) and boxing glove (144.40 ± 17.39°) at p = 0.269. The perpendicular distance from the second metacarpal of the hand to the center of the MP joint was significantly different between no glove (0.48 ± 0.54 cm) and boxing glove (1.84 ± 0.29 cm) at p ≤ 0.001. Use of a boxing glove resulted in abduction of the thumb away from the hand and increased CMC and MP joint angles that were significantly different in relation to making a fist without a glove. Information from this study may provide insight into the high rate of thumb injury and provide insight for future boxing glove design.


Assuntos
Desenho de Equipamento , Polegar , Humanos , Polegar/fisiologia , Adulto , Masculino , Boxe/fisiologia , Articulação Metacarpofalângica/fisiologia , Articulações Carpometacarpais , Adulto Jovem , Luvas Protetoras
4.
J Strength Cond Res ; 38(9): 1627-1634, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38985931

RESUMO

ABSTRACT: Dunican, IC, Galpin, A, Turner, M, and Reale, R. Sleep behaviors and nutritional knowledge in amateur and professional combat sport athletes. J Strength Cond Res 38(9): 1627-1634, 2024-Combat sports is a term applied to various competitive contact sports involving 2 competitors engaging in a bout or contest under a specific ruleset. Little is known about combat sports athletes' sleep and nutritional knowledge. This study aimed to assess (a) sleep behaviors, (b) alcohol and shiftwork disorders, and (c) the nutritional knowledge of combat sports athletes. Subjects completed various demographic questions and estimations of their weight management practices and validated surveys, including the Athlete Sleep Behavior Questionnaire, Shiftwork Disorder (SWD) Screening Questionnaire, Alcohol Use Disorders Identification Test, and the Abridged Nutrition for Sports Knowledge Questionnaire. A total of 844 combat sports athletes completed the survey, 79% male, height of 177 ± 10 (cm), and body mass of 79 ± 15 (kg). Subjects were categorized into their specific combat sport type (e.g., boxing or Brazilian jiu-jitsu [BJJ]) and by their level (professional or amateur). Sleep quality was average for all combat sport types and risk prevalence of shiftwork disorder at 11%. Mann-Whitney U tests revealed that amateurs, compared with professional strikers ( p = 0.046, CLES = 0.80), boxers ( p = 0.01, CLES = 0.78), and BJJ ( p = 0.046, CLES = 0.61) athletes, consumed significantly more alcohol. A Friedman test showed significant ( p < 0.001, W = 0.51) differences in weight between time points, with most combat sports athletes reducing weight for competition. An overall nutritional knowledge average of 55% was reported. This study highlights a critical gap in the knowledge and practices of combat sports athletes in relation to sleep behaviors and disorders, alcohol consumption, and nutritional knowledge, emphasizing the need for targeted educational interventions.


Assuntos
Atletas , Conhecimentos, Atitudes e Prática em Saúde , Sono , Humanos , Masculino , Feminino , Sono/fisiologia , Atletas/estatística & dados numéricos , Adulto Jovem , Adulto , Inquéritos e Questionários , Boxe/fisiologia , Artes Marciais/fisiologia , Adolescente , Jornada de Trabalho em Turnos
5.
J Strength Cond Res ; 38(6): 1063-1071, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349345

RESUMO

ABSTRACT: Finlay, MJ, Greig, M, Bridge, CA, and Page, RM. Post-activation performance enhancement of punch force and neuromuscular performance in amateur boxing: Toward a more individualized and "real-world" approach. J Strength Cond Res 38(6): 1063-1071, 2024-Previous research on post-activation performance enhancement has been applied in several sporting settings, although this is lacking in a boxing setting. This study explored the effectiveness of 2 upper-body conditioning activities in improving punch-specific performance during an amateur boxing-simulated bout. On 3 separate occasions, 10 male senior elite amateur boxers performed the following conditioning activities before a boxing-specific simulation protocol: isometric (ISO) punch, elastic resistance (ER) punch, and a control trial. Boxers performed maximal punches against a vertically mounted force plate, and countermovement jumps (CMJ) at baseline, before round 1, after each round, and 4 minutes after the simulation. Both conditioning activities, but not the control trial, produced small worthwhile increases (effect size ≥ 0.20; equal to or greater than the smallest worthwhile change) in punch force, although worthwhile increases in rate of force development were limited to the cross during the ISO trial. No group-based improvements in CMJ performance were observed. Individual analysis revealed that 6 boxers improved punch-specific performance to the greatest extent in the ISO trial; in contrast, only 1 boxer did so in the ER trial. Three boxers exhibited similar performance increases across trials. In conclusion, both conditioning activities may be applied to an amateur boxer's warm-up to acutely enhance punch-specific performance. The ISO conditioning activity seems most effective; however, the interindividual variability suggests a need for protocols to be individualized to each athlete. The conditioning activities in the present study may be applied to sparring, competitive bouts, or to other combat sports.


Assuntos
Desempenho Atlético , Boxe , Força Muscular , Humanos , Masculino , Desempenho Atlético/fisiologia , Boxe/fisiologia , Adulto Jovem , Força Muscular/fisiologia , Treinamento Resistido/métodos , Treinamento Resistido/instrumentação , Contração Isométrica/fisiologia , Adulto , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Músculo Esquelético/fisiologia
6.
J Sports Sci ; 40(5): 509-517, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34930100

RESUMO

Head impacts and neurocognition were quantified in 27 intercollegiate male boxers engaged in two, two-minute sparring rounds. Head impacts were measured using Instrumented Boxing Headgear (IBH). Pre and post-sparring neurocognitive performance was compared using two computerized neuropsychological test batteries (CNTs): Immediate Post-concussion Assessment and Cognitive Testing (ImPACT™) and Automated Neuropsychological Assessment Metrics - Military Battery (ANAM4® MIL). An average of 27.63 ± 17.87 impacts above the 9.6 g IBH threshold were recorded per boxer, with average peak linear acceleration of 23.48 ± 15.20 g and average peak rotational acceleration of 1761.40 ± 1064.34 rad/s2. Small, but measurable declines in delayed memory and improvement in response time from pre- to post-bout were noted. Number of impacts and concussion history predicted degraded memory performance. This is a unique quantification of head impacts in collegiate boxing, which were similar in frequency and location, but lower in magnitude as compared to amateur boxing. Improved understanding of impact kinematics may enhance safety in boxing and other contact sports. Subtle post-bout decrements in delayed memory performance and mild improvement in response time reinforce prior research and provide evidence of congruence in our two CNT assessments, which may facilitate comparisons of outcomes across settings utilizing these tests.


Assuntos
Boxe , Concussão Encefálica , Aceleração , Boxe/fisiologia , Concussão Encefálica/diagnóstico , Cognição , Humanos , Masculino , Testes Neuropsicológicos
7.
J Strength Cond Res ; 36(7): 1966-1971, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35510889

RESUMO

ABSTRACT: Stone, BL, Ashley, JD, Skinner, RM, Polanco, JP, Walters, MT, Schilling, BK, and Kellawan, JM. Effects of a short-term heat acclimation protocol in elite amateur boxers. J Strength Cond Res 36(7): 1966-1971, 2022-Boxing requires proficient technical and tactical skills coupled with high levels of physiological capacity. Although heat and humidity negatively affect acute exercise performance, short-term exercise training in hot and humid environments can lead to physiological adaptations that enhance exercise performance in both hot and thermoneutral conditions. In highly trained endurance athletes, exercise-induced acclimation can occur in as little as 5 days (known as short-term heat acclimation [STHA]). However, the impact of a 5-day heat acclimation (5-DayHA) in combat athletes, such as elite amateur boxers, is unknown. The aim of the present investigation was to determine whether a 5-DayHA improves aerobic performance in a thermoneutral environment and causes positive physiological adaptations in elite boxers. Seven elite amateur boxers underwent a 5-DayHA protocol, consisting of 60-minute exercise sessions in an environmental chamber at 32 °C and 70% relative humidity. Repeat sprint test (RST) evaluated aerobic performance in a thermoneutral environment 24 hours before and after the 5-DayHA. Presession and postsession hydration status (urine specific gravity) and body mass were assessed. After a 5-DayHA period, boxers significantly improved RST performance (13 ± 7 to 19 ± 7 sprints, d = 0.92, p = 0.03) but not pre-exercise hydration status (1.02 ± 0.01 to 1.01 ± 0.01, d = 0.82, p = 0.07). Therefore, these findings suggest 5-DayHA enhances aerobic performance in elite-level amateur boxers and may provide a viable training option for elite combat athletes.


Assuntos
Boxe , Temperatura Alta , Aclimatação/fisiologia , Atletas , Boxe/fisiologia , Exercício Físico/fisiologia , Humanos
8.
J Strength Cond Res ; 36(3): 717-722, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32118701

RESUMO

ABSTRACT: Venckunas, T, Bruzas, V, Stasiulis, A, Snieckus, A, Mockus, P, and Kamandulis, S. Cardiorespiratory responses to specific and non-specific exercise in high-profile amateur boxers. J Strength Cond Res 36(3): 717-722, 2022-Our aim was to compare cardiorespiratory responses in 3 types of all-out exercises (upper body, lower body, and punching) in well-trained boxers and peak heart rate (HR) in these tests with HR response to competitive Olympic boxing. On 4 separate occasions, 11 male amateur boxers performed: (a) progressive treadmill running to exhaustion; (b) progressive arm cranking to failure; (c) progressive bag punching to maximal exertion; and (d) competitive boxing fight (3 × 3 minutes format). Expired gas and HR were measured in all tasks except in the full-contact competitive fight where only HR was recorded. Peak oxygen uptake (55.3 ± 5.9 ml·kg-1·min-1) was highest during treadmill running. Peak respiratory exchange ratio was highest during bag punching (1.26 ± 0.09), but did not differ between arm cranking and running. Peak HR of the boxing fight (197.7 ± 5.9 b·min-1) did not differ from that of running (196.5 ± 8.7 b·min-1), but was smaller in arm cranking (179.8 ± 9.2) and bag punching (184.1 ± 12.2 b·min-1). The correlation coefficients between peak HR achieved during competitive fighting and that achieved during running, arm cranking and bag punching were 0.720 (p = 0.013), 0.597 (p = 0.052), and 0.702 (p = 0.035), respectively. In conclusion, in high-profile amateur boxers, running evoked a higher cardiorespiratory activation than arm cranking or bag punching, whereas punching elicited the highest input of anaerobic glycolysis. Peak HR of competitive fighting was the same as during running and much higher than during arm cranking or bag punching.


Assuntos
Boxe , Esportes , Braço , Boxe/fisiologia , Exercício Físico , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
9.
J Strength Cond Res ; 34(4): 1040-1051, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30789570

RESUMO

Lenetsky, S, Brughelli, M, Nates, RJ, Neville, JG, Cross, MR, and Lormier, AV. Defining the phases of boxing punches: A mixed-method approach. J Strength Cond Res 34(4): 1040-1051, 2020-Current research on punching in boxing has explored both kinematic and kinetic variables; however, there is no shared structure in the literature to describe these findings. A common method used to provide a shared structure in other sporting tasks is the definition of movement phases. To define the phases of 4 punches used in boxing (lead punches and rear straight and hook punches), 10 experienced and competitive boxers (age = 25.6 ± 5.97 years, height = 179.5 ± 7.72 cm, body mass = 95.66 ± 21.82 kg, and years training = 10.3 ± 5.97 years) were tested while performing maximal-effort punches. Ground reaction forces (GRFs), electromyographic, high-speed video (HSV), and striking dynamometry data were collected during all punches. A mixed-method approach was used to define the phases for each punch type based on the GRF measurements and impact timing from the striking dynamometer. Electromyographic and HSV data were then used to develop a more holistic understanding of punching actions by elaborating on the description of each phase. The final outcome of this approach has produced definitions for the phases of straight and hook punches, a greater qualitative understanding of said punches, and most importantly, a structure for current and future punching-related research, and a context to improve coach/sport scientist communication.


Assuntos
Boxe/fisiologia , Movimento/fisiologia , Adulto , Fenômenos Biomecânicos , Eletromiografia , Humanos , Masculino , Dinamômetro de Força Muscular , Esportes , Gravação de Videoteipe , Adulto Jovem
10.
J Strength Cond Res ; 34(2): 308-312, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31469761

RESUMO

López-Laval, I, Sitko, S, Muñiz-Pardos, B, Cirer-Sastre, R, and Calleja-González, J. Relationship between bench press strength and punch performance in male professional boxers. J Strength Cond Res 34(2): 308-312, 2020-This study investigated the relationship between punching performance and the velocity at which different loads were lifted during the bench press (BP) exercise in 12 professional boxers (age = 22.6 ± 4 years; height = 177.7 ± 5 cm; body mass 70.6 ± 6.43 kg; years of boxing experience = 6.5 ± 3.5 years; weight class = from light to super welterweight). To determine the maximal punching velocity (PVmax) during both rear arm (RA) and lead arm (LA) punching, an accelerometer (Crossbow; Willow Technologies, Sussex, United Kingdom) was placed inside the boxing glove while executing 3 jabs at a maximal velocity with each arm. Upper-body strength was assessed through the direct 1-repetition maximum (1RM) BP test, and the maximum velocity at different percentages of 1RM was obtained with a linear encoder. The main finding was that RA PVmax was correlated with the BP velocity at all submaximal intensities (p < 0.05). Nevertheless, LA PVmax did not correlate with BP velocity at any intensity. When the correlated BP submaximal intensities were introduced in linear regression models, the velocity at 80% 1RM was the only predictor of RA PVmax (r = 0.75; p < 0.01) in professional boxers. Additional body mass adjustment to the regression model significantly affected the predictive value (r = 0.65; p < 0.005). Results encourage coaches and trainers to use BP exercise with high loads (i.e., 80% of 1RM) because this could be a reliable predictor of performance during the specific boxing action. Future research is needed to determine exercises and intensities that could explain LA PVmax because significant associations were not found.


Assuntos
Desempenho Atlético/fisiologia , Boxe/fisiologia , Força Muscular/fisiologia , Levantamento de Peso/fisiologia , Acelerometria/instrumentação , Estudos Transversais , Humanos , Modelos Lineares , Masculino , Adulto Jovem
11.
J Strength Cond Res ; 34(4): 1052-1061, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30358696

RESUMO

Finlay, MJ, Greig, M, McCarthy, J, and Page, RM. Physical response to pad- and bag-based boxing-specific training modalities. J Strength Cond Res 34(4): 1052-1061, 2020-This study examined the differences in the physical response elicited from a contemporary Boxing-Specific Exercise Protocol (BSEP) performed using a punch bag and a pad routine. Fourteen male elite amateur boxers (age = 22 ± 2 years; height = 176.9 ± 7.3 cm; body mass = 78.8 ± 8.7 kg; and V[Combining Dot Above]O2max = 55.94 ± 5.96 ml·kg·min) were recruited. The BSEP comprised 3 × 3-minute rounds. Average (HRave) and peak (HRpeak) heart rate, average (V[Combining Dot Above]O2ave) and peak oxygen consumption (V[Combining Dot Above]O2peak), blood lactate (BLa) concentrations, rating of perceived exertion (RPE), and both triaxial and uniaxial PlayerLoad metrics were recorded during each trial. The PlayerLoad metrics were recorded at both the cervical and lumbar spine. BLa increased significantly across rounds, with higher values recorded in the pad trial (pad = 2.7 ± 0.8 mmol·L; bag = 2.3 ± 0.9 mmol·L). A similar response was also identified for the HRave (pad = 160 ± 9 b·min; bag = 150 ± 16 b·min) and V[Combining Dot Above]O2ave data (pad = 38.00 ± 0.31 ml·kg·min; bag = 34.40 ± 1.06 ml·kg·min). A significant main effect for time was also recorded for the RPE data; however, there were no significant differences between trials. Conversely, the triaxial (PLTotal) and medial-lateral (PLML) data were higher in the punch bag trial. There was also a main effect for time for all the PlayerLoad metrics. PLTotal, PLML, and vertical PlayerLoad were significantly higher in the lumbar region when compared with the cervical region. With implications for boxing-specific conditioning, the pad routine was more physiologically demanding, but less mechanically demanding than the bag routine.


Assuntos
Boxe/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Cross-Over , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Consumo de Oxigênio/fisiologia , Adulto Jovem
12.
Medicina (Kaunas) ; 55(6)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216765

RESUMO

Background and objectives: Boxing is a popular combat sport that requires high intensity and cooperation. However, there are limited data about the influence of boxing matches on blood parameters. The purpose of the present study was to investigate the match-induced changes in the metabolic, hormonal, and inflammatory status in male elite boxers. Materials and methods: High-level 20 male boxers with more than 5 years experience in boxing voluntarily participated in this study. Venous blood samples of the boxers, before and after combat, were taken for determination of the plasma parameters. Results: Our results indicated that a 9-min boxing match caused significant increases in plasma energy fuels (glucose and lactate), metabolic hormones (insulin, adrenocorticotropic hormone (ACTH), cortisol, and growth hormone), inflammatory markers (interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α)), muscle damage indicators (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)), and oxidative stress marker (SOD). A decrease in total oxidant status (TOS) was also considered. However, there were no significant alterations in the plasma levels of androgenic hormone (free and total testosterone), anabolic hormone (IGF-1), lipids (total cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL)), kidney function markers (creatinine and urea), and minerals (iron (Fe) and magnesium (Mg)). Conclusion: Elevations in the level of energy fuels and metabolic hormones of the boxers could be taken as a reflection of high-energy turnover during combat performance. The increases in inflammatory and tissue damage indicators may possibly be an indication of traumatic injury. Understanding the biochemical changes that occur during boxing match could be valuable to optimize the performance improvement of the athletes.


Assuntos
Atletas , Boxe/fisiologia , Metabolismo/fisiologia , Hormônio Adrenocorticotrópico/análise , Hormônio Adrenocorticotrópico/sangue , Adulto , Alanina Transaminase/análise , Alanina Transaminase/sangue , Aspartato Aminotransferases/análise , Aspartato Aminotransferases/sangue , Glucose/análise , Hormônio do Crescimento/análise , Hormônio do Crescimento/sangue , Humanos , Hidrocortisona/análise , Hidrocortisona/sangue , Insulina/análise , Insulina/sangue , Interleucina-1beta/análise , Interleucina-1beta/sangue , Ácido Láctico/análise , Ácido Láctico/sangue , Masculino , Estresse Oxidativo/fisiologia , Tailândia
13.
Arch Phys Med Rehabil ; 99(5): 927-933, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29428343

RESUMO

OBJECTIVE: To evaluate whether virtual reality games (VRGs) in stroke survivors produce significant and reproducible heart rate and oxygen consumption (V˙o2) responses during their execution, corresponding to an intensity between the anaerobic threshold (AT) and the respiratory compensation point (RCP). DESIGN: Single-subject, repeated-measure design. SETTING: Stroke survivors registered from a rehabilitation program. PARTICIPANTS: Chronic hemiparetic stroke survivors (N=12; 10 men; mean age ± SD, 58±12y) rated at 3 or 4 in the Functional Ambulation Categories. INTERVENTIONS: Participants underwent, in a random order, 2 identical sessions of VRGs (console Xbox 360 + Kinect) and 1 control session (38min watching a movie). The VRG sessions were composed of 4 sets of VRGs (3min of tennis, 1min for changing the game, and 4min of boxing) interspaced with 2 minutes of rest. MAIN OUTCOME MEASURES: Heart rate and V˙o2 were measured during the experimental sessions and compared with heart rate and V˙o2 obtained at AT and RCP assessed during a maximal cardiopulmonary exercise test. RESULTS: Heart rate and V˙o2 during VRGs had good reproducibility (intraclass correlation coefficients, ≥.91 and ≥.85, respectively; coefficients of variation, ≤6.7% and ≤13.7%, respectively). Heart rate during VRGs was similar to AT and significantly lower than RCP (P≤.05), while V˙o2 was significantly lower than AT and RCP (P<.05). CONCLUSIONS: An acute session of VRGs composed of tennis and boxing games using the console XBox 360 + Kinect promotes reproducible responses of heart rate and V˙o2 that corresponded, respectively, to AT and below AT, characterizing a low-intensity aerobic stimulus.


Assuntos
Exercício Físico , Paresia/reabilitação , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Jogos de Vídeo , Idoso , Limiar Anaeróbio , Boxe/fisiologia , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Paresia/etiologia , Acidente Vascular Cerebral/complicações , Tênis/fisiologia , Realidade Virtual
14.
J Strength Cond Res ; 32(7): 1838-1842, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29420389

RESUMO

Lenetsky, S, Brughelli, M, Nates, RJ, Cross, MR, and Lormier, AV. Variability and reliability of punching impact kinetics in untrained participants and experienced boxers. J Strength Cond Res 32(7): 1838-1842, 2017-Striking impact kinetics are central to performance in combat sports. Despite a multitude of assessment, few in the literature have explored the variability and reliability of punching force assessment. Consequently, this study assessed the variability and reliability of measured punching impact kinetics in untrained and experienced boxers using a recently developed and validated method of striking dynamometry. Intrasession (both cohorts) and intersession (untrained only) measures of impulse, peak, and mean force were determined across 4 punch types (jabs, crosses, lead, and rear hand hooks) using coefficient of variation (CV), intraclass correlation coefficients (ICCs), and typical error of measurement (TEM). Moderate (ICC <0.67 or CV >10%) to small (ICC >0.67 and CV <10%) variability was found for intrasession results of both groups, the majority having small variability. Intersession findings of the untrained cohort had a similar spread of variability, but with the majority exhibiting moderate variability. All variables except for mean force of the cross in the experienced boxer cohort were found to exhibit a "moderated" magnitude of reliability determined by standardized TEM scores (TEM = 0.60-1.19) during intrasession testing. All variables had moderate reliability during intersession. This method was found to have acceptable variability and reliability when monitoring punching impact kinetics.


Assuntos
Boxe/fisiologia , Acelerometria , Adulto , Humanos , Cinética , Masculino , Força Muscular , Reprodutibilidade dos Testes , Adulto Jovem
15.
J Strength Cond Res ; 32(5): 1214-1221, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28800004

RESUMO

Kamandulis, S, Bruzas, V, Mockus, P, Stasiulis, A, Snieckus, A, and Venckunas, T. Sport-specific repeated sprint training improves punching ability and upper-body aerobic power in experienced amateur boxers. J Strength Cond Res 32(5): 1214-1221, 2018-High-intensity interval training improves endurance and performance, but it is unclear whether sprint-type upper-body interval training is similarly effective. This study explored the effects of 4-week sport-specific sprint interval training on punch characteristics and endurance capacity in boxers. Experienced male amateur boxers (n = 18) participated in this 4-week training study and were divided into an experimental group (EG) and a control group (CG) (n = 9 per group). Both groups completed standard low-intensity training. The EG also completed 3 rounds (14 sets of 3-second all-out punching with a 10-second rest) of a simulated fight using a punching bag with a 1-minute rest between rounds 3 times per week, whereas the CG performed the same 3 rounds of a simulated fight at low intensity. Three rounds of 14 sets of 3-second all-out punching of a bag ergometer with a 10-second rest were performed to measure punching abilities. Peak oxygen consumption and peak power were measured during progressive arm cranking before and after training. In response to training peak oxygen consumption and peak power in arm-cranking test increased in EG, also punching force increased and maintenance of punching frequency and punch force improved during the simulated fight, which resulted in greater cumulative force throughout the 3 rounds. There were no changes in the CG. The study shows that 1 month of all-out punching training (3 sessions per week with ∼2 minutes of all-out punching per session) improved both upper-body aerobic power and punching abilities in experienced amateur boxers.


Assuntos
Boxe/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Humanos , Masculino , Descanso
16.
J Strength Cond Res ; 32(4): 1005-1012, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29570596

RESUMO

Finlay, MJ, Greig, M, and Page, RM. Quantifying the physical response to a contemporary amateur boxing simulation. J Strength Cond Res 32(4): 1005-1012, 2018-This study examined the physical response to a contemporary boxing-specific exercise protocol (BSEP), based on notational analysis of amateur boxing. Nine male senior elite amateur boxers completed a 3 × 3-minute BSEP, with a 1-minute passive recovery period interspersing each round. Average (HRave) and peak (HRpeak) heart rates, average (V[Combining Dot Above]O2ave) and peak oxygen consumptions (V[Combining Dot Above]O2peak), blood lactate (BLa) concentrations, rating of perceived exertion, and both triaxial and uniaxial PlayerLoad metrics were recorded during the completion of the BSEP. Blood lactate concentration increased significantly in each round (Round 1 = 2.4 ± 1.3 mmol·L; Round 2 = 3.3 ± 1.7 mmol·L; Round 3 = 4.3 ± 2.6 mmol·L). Significantly lower HRave and HRpeak values were found in the first round (HRave: 150 ± 15 b·min; HRpeak: 162 ± 12 b·min) when compared with the second (HRave: 156 ± 16 b·min; HRpeak: 166 ± 13 b·min) and third (HRave: 150 ± 15 b·min; HRpeak: 169 ± 14 b·min). No significant differences were found in any of the V[Combining Dot Above]O2 or PlayerLoad metrics recorded during the BSEP. The BSEP based on notational analysis elicited a fatigue response across rounds, confirming its validity. The BSEP can be used as a training tool for boxing-specific conditioning with implications for reduced injury risk, and to assess the physical response to boxing-specific interventions. Moreover, the BSEP can also be manipulated to suit all levels of participants or training phases, with practical applications in performance monitoring and microcycle periodization.


Assuntos
Boxe/fisiologia , Adulto , Exercício Físico/fisiologia , Fadiga/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Ácido Láctico/sangue , Masculino , Óxido Nítrico , Consumo de Oxigênio/fisiologia , Adulto Jovem
17.
Ergonomics ; 61(2): 255-264, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28679350

RESUMO

Work breaks are known to have positive effects on employees' health, performance and safety. Using a sample of twelve employees working in a stressful and cognitively demanding working environment, this experimental field study examined how different types of work breaks (boxing, deep relaxation and usual breaks) affect participants' mood, cognitive performance and neurophysiological state compared to a control condition without any break. In a repeated measures experimental design, cognitive performance was assessed using an auditory oddball test and a Movement Detection Test. Brain cortical activity was recorded using electroencephalography. Individual's mood was analysed using a profile of mood state. Although neurophysiological data showed improved relaxation of cortical state after boxing (vs. 'no break' and 'deep relaxation'), neither performance nor mood assessment showed similar results. It remains questionable whether there is a universal work break type that has beneficial effects for all individuals. Practitioner Summary: Research on work breaks and their positive effects on employees' health and performance often disregards break activities. This experimental field study in a stressful working environment investigated the effect of different work break activities. A universal work break type that is beneficial for this workplace could not be identified.


Assuntos
Boxe , Relaxamento , Descanso , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia , Carga de Trabalho , Adulto , Afeto , Boxe/fisiologia , Boxe/psicologia , Cognição , Eletroencefalografia , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Relaxamento/fisiologia , Relaxamento/psicologia , Descanso/fisiologia , Descanso/psicologia , Carga de Trabalho/psicologia
18.
Psychol Res ; 81(5): 1051-1058, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27465395

RESUMO

While self-controlled practice has been shown to enhance motor learning with various populations and novel tasks, it remains unclear if such effects would be found with athletes completing familiar tasks. Study 1 used a single case-study design with a world-champion kickboxer. We investigated whether giving the athlete a choice over the order of punches would affect punching velocity and impact force. Separated by 1 min of rest, the athlete completed 2 rounds of 12 single, maximal effort punches (lead straight, rear straight, lead hook and rear hook) delivered to a punching integrator in a counterbalanced order over six testing days. In one round the punches were delivered in a predetermined order while in the second round the order was self-selected by the athlete. In the choice condition, the world champion punched with greater velocities (6-11 %) and impact forces (5-10 %). In Study 2, the same testing procedures were repeated with 13 amateur male kickboxers over 2 testing days. Similar to Study 1, the athletes punched with significantly greater velocities (6 %, p < 0.05) and normalised impact forces (2 %, p < 0.05) in the choice condition. These findings complement research on autonomy support in motor learning by demonstrating immediate advantages in force production and velocity with experienced athletes.


Assuntos
Atletas/psicologia , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Boxe/fisiologia , Boxe/psicologia , Comportamento de Escolha/fisiologia , Atividade Motora/fisiologia , Adulto , Humanos , Masculino
19.
J Sports Sci ; 35(8): 719-726, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27173991

RESUMO

This study investigated (i) the prevalence of hypohydration and (ii) association between urinary indices of hydration status and confounding factors (e.g., urine protein content, water intake) in elite youth boxers during their weight-stable phase before competition. Sixteen national champion boxers (all male, 17 ± 1 y) were measured on 3 occasions (baseline, day 3, day 10), 30-day prior to competition. Body mass, total body water, urine specific gravity (USG), osmolality (UOSM) and total protein content (TPC) were evaluated to determine hydration status and fluid balance. Overall macronutrient and water intake were assessed using dietary records. Both UOSM and USG increased from day 3 to day 10 by 16% and 0.4% (P < 0.001), despite athletes being in their weight-stability period, and regardless of ad libitum fluid intake. Hypohydration was universally prevalent among all athletes on both test days with USG: 1.027 ± 0.003 g · mL-1 and UOSM: 1035 ± 108 mOsmol · kg-1. An inverse association between mean UOSM values and mean water intake was observed (R = -0.52, P = 0.04), while TPC was not associated with any urinary dehydration markers (USG, P = 0.51; UOSM, P = 0.61). The present outcomes find that the most prevalent urinary dehydration markers used to classify hydration status in competition exhibit large variability, even during weight-stable periods.


Assuntos
Boxe/fisiologia , Comportamento Competitivo/fisiologia , Desidratação/diagnóstico , Equilíbrio Hidroeletrolítico/fisiologia , Adolescente , Biomarcadores/urina , Índice de Massa Corporal , Desidratação/urina , Dieta , Ingestão de Líquidos , Humanos , Masculino , Proteinúria , Urina/química
20.
J Strength Cond Res ; 31(1): 95-105, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27191695

RESUMO

Cunniffe, B, Ellison, M, Loosemore, M, and Cardinale, M. Warm-up practices in elite boxing athletes: Iimpact on power output. J Strength Cond Res 31(1): 95-105, 2017-This study evaluated the performance impact of routine warm-up strategies in elite Olympic amateur boxing athletes and physiological implications of the time gap (GAP) between warm-up and boxing activity. Six male boxers were assessed while performing standardized prefight warm-up routines. Core and skin temperature measurements (Tcore and Tskin), heart rate, and upper- and lower-body power output (PO) were assessed before and after warm-up, during a 25-minutes GAP and after 3 × 2 minutes rounds of sparring. Reflected temperature (Tc) was also determined using high-resolution thermal images at fixed time-points to explore avenues for heat loss. Despite individual differences in warm-up duration (range 7.4-18.5 minutes), increases in Tcore and Tskin occurred (p ≤ 0.05). Corresponding increases (4.8%; p ≤ 0.05) in countermovement jump (CMJ) height and upward-rightward shifts in upper-body force-velocity and power-velocity curves were observed. Athletes remained inactive during the 25-minutes GAP with a gradual and significant increase in Tc occurring by the end of GAP suggesting the likelihood of heat loss. Decreases in CMJ height and upper-body PO were observed after 15 minutes and 25 minutes GAP (p ≤ 0.05). By the end of GAP period, all performance variables had returned to pre-warm-up values. Results suggest routine warm-ups undertaken by elite boxers have acute effects on power-generating capacity. Gradual decreases in performance variables are evident with inactivity and seem related to alterations in body temperature. Considering the constraints of major competitions and time spent in air conditioned holding areas before fights, practitioners should be aware of the potential of nullifying the warm-up effects.


Assuntos
Desempenho Atlético/fisiologia , Boxe/fisiologia , Exercício de Aquecimento/fisiologia , Adulto , Atletas , Temperatura Corporal/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA