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1.
Percept Mot Skills ; 130(3): 1168-1184, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36992665

RESUMEN

This study was conducted to determine whether the relative age effect (RAE) is present in different age groups, weight categories, sexes, and across different time frames in international-level judo competition. A total of 9451 judo athletes competing at the Olympic Games and/or World Championships in the Cadet, Junior and/or Senior age groups between 1993 and 2020 were considered. Athletes' birthdate distributions were grouped in four quartiles (Q1: January-March; Q2: April-June; Q3: July-September; Q4: October-December) and compared to a day-corrected theoretical distribution using Chi-squared analysis. Poisson regression was also used to evaluate the ability to explain weekly birth count. RAE was more prevalent in males than females (p < .05), and for Cadets and Juniors compared to Seniors (p < .05). Heavyweight and middleweight categories presented RAEs in Senior and Junior males, while for females it was present in Cadet heavyweights (p < .05). RAE was more prevalent in recent years (2009-2021) for Senior male judo athletes (p < .05). Poisson analysis illustrated some nuanced information, including RAE detection during an earlier time frame, not readily apparent with the traditional analysis.


Asunto(s)
Rendimiento Atlético , Artes Marciales , Femenino , Humanos , Masculino , Factores de Edad , Atletas
2.
Artículo en Inglés | MEDLINE | ID: mdl-36554612

RESUMEN

Physical fitness is one of the most important physical and mental health aspects for children with Autism Spectrum Disorder (ASD). This study aimed to test the effects of a long-term adapted judo program on the health-related physical fitness of children with ASD. The participants were recruited from various associations of families and schools for children with special needs. Twenty-one children were assigned to an experimental group and nineteen to a control group. The experimental group participated in a six-month adapted judo program consisting of 90 min of practice each week. Health-related physical fitness was measured using the indicators obtained from the ALPHA-fitness battery, the estimated VO2max and the waist/height ratio0.5. Changes within and between groups were analyzed using linear mixed models for repeated measures designs and test-retest reliability of tests requiring a maximum score using the Intraclass Correlation Coefficient (ICC). A judo program tailored for children with ASD can improve the cardio-metabolic health and cardiorespiratory fitness of its participants. The problems involved with administering physical aptitude tests that involve maximum effort or performance in children with ASD cast serious doubts on the reproducibility of their results.


Asunto(s)
Trastorno del Espectro Autista , Artes Marciales , Humanos , Niño , Reproducibilidad de los Resultados , Aptitud Física , Ejercicio Físico
3.
J Int Soc Sports Nutr ; 19(1): 638-649, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36419615

RESUMEN

Background: The demands of typical daily activities require a constant level of alertness and attention. Multi-ingredient, caffeine-containing supplements have been shown to improve measures of cognitive performance. As many of these supplements become readily available, efficacy of each should be evaluated. Therefore, the purpose of this study is to examine the effects of the 4D dietary supplement on cognition, reaction time, and reactive agility. Methods: Seventeen healthy males (n = 8) and females (n = 9) between the ages of 18-40 years old (22.8 ± 2.9 years; 167.3 ± 9.6 cm; 65.4 ± 10.9 kg) participated in this double-blind, randomized crossover study. Participants completed three baseline reaction time assessments on the Dynavision and one baseline multiple object tracking assessment on the Neurotracker. Participants then consumed the oral multi-ingredient supplement containing 150 mg of caffeine or non-caffeinated placebo, mixed with 24 ounces of water, and rested for 45 minutes. Following the rest period, participants completed an additional three reaction time assessments and one multiple object tracking (MOT) assessment, as well as 6-12 trials of the Y-reactive agility test. Repeated measures ANOVAs were used to evaluate YRA performance and change values for Dynavision RT, Dynavision score, and MOT speed with either 4D dietary supplement or placebo. Results: A significant time × supplement interaction was shown for MOT speed (p = .040, d = .543). Change scores in MOT speed were significantly different from zero following 4D (mean: 0.224 au; 95% confidence interval: 0.050 to 0.398 au) but not placebo supplementation (mean: -0.046 au; 95% confidence interval: -0.220 to 0.127 au). No time × supplement interaction was shown for Dynavision RT (p = .056, d = -.499) or Dynavision score (p = .093, d = .434). No differences were shown for YRA scores following supplementation for the right side (p = .241, d = -.295) or left side (p = .378, d = -.220). Conclusion: The 4D dietary supplement appears to improve measures of cognition, specifically attention/spatial awareness, but not reaction time or reactive agility. Future research should examine the effects of this supplement with a larger, less heterogeneous sample and/or in conjunction with an exercise intervention.


Asunto(s)
Cafeína , Suplementos Dietéticos , Masculino , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Cafeína/farmacología , Estudios Cruzados , Tiempo de Reacción , Descanso
4.
J Am Nutr Assoc ; 41(6): 541-550, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34252340

RESUMEN

OBJECTIVE: The purpose of the present study was to examine the effect of capsiate supplementation on energy intake, self-reported appetite-related sensations, energy expenditure, fat oxidation, and autonomic parameters with and without an exercise intervention. METHODS: Thirteen healthy men completed four randomized trials: two trials for the control condition (without exercise), one with capsiate supplementation (CTRLcap) and one with a placebo (CTRLpla), and two trials for the exercise condition, one with capsiate supplementation (EXcap) and one with placebo (EXpla). Exercise sessions were performed 150 min after the consumption of a standardized breakfast, and supplementation 115 min after consumption of breakfast. An ad libitum buffet was offered 200 min following the completion of the standardized breakfast, and energy intake (EI) and relative energy intake (REI) (relative energy intake = energy intake - energy expenditure related to exercise) were evaluated. RESULTS: There were no significant effects on EI, self-reported appetite sensations, fat oxidation, and energy expenditure. REI was reduced in conditions involving EX when compared to CTRL. A low-frequency to high-frequency ratio for heart rate variability was higher in CTRLcap (1.6 ± 1.1) vs. CTRLpla (1.2 ± 0.9) (p = 0.025; d = 0.39). CONCLUSION: Acute capsiate supplementation combined with aerobic exercise has limited effects on the examined variables (EI, REI, fat oxidation, energy expenditure, and autonomic parameters), while changes in the autonomic nervous system function in the absence of exercise may have occurred without influencing other variables. CLINICAL TRIAL REGISTRATION: ensaiosclinicos.gov.br number, RBR-5pckyr https://ensaiosclinicos.gov.br/rg/RBR-5pckyr.


Asunto(s)
Apetito , Ingestión de Energía , Apetito/fisiología , Capsaicina/análogos & derivados , Suplementos Dietéticos , Ingestión de Energía/fisiología , Ejercicio Físico/fisiología , Humanos , Masculino
5.
Artículo en Inglés | MEDLINE | ID: mdl-34444263

RESUMEN

The public health lockdown prompted by the novel coronavirus (COVID-19) pandemic, which included school closures that may have potentially serious consequences for people with disabilities or special educational needs, disrupted an ongoing adapted judo training intervention in children with Autism Spectrum Disorder (ASD). The purpose of this study was to compare repetitive behaviours, social interaction, social communication, emotional responses, cognitive style and maladaptive speech scores across four time-points: baseline, after an eight-week control period, after an eight-week judo intervention and after an eight-week lockdown period due to COVID-19. The sample consisted of 11 children diagnosed with ASD according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-V), with an intelligence quotient (IQ) range between 60 and 70. Significant improvements were shown following the judo intervention period compared to the baseline and control periods. However, the same values significantly declined during the COVID-19 lockdown period resulting in values lower than those recorded at baseline, and following the control period and the judo intervention. The decline in psychosocial and behavioural scores are likely due to the stress caused by the sudden halt in activity and the increase in sedentary practices associated with the lockdown.


Asunto(s)
Trastorno del Espectro Autista , COVID-19 , Artes Marciales , Trastorno del Espectro Autista/epidemiología , Trastorno del Espectro Autista/terapia , Niño , Control de Enfermedades Transmisibles , Humanos , SARS-CoV-2
6.
Nutrients ; 13(6)2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34071875

RESUMEN

Numerous health conditions affecting the musculoskeletal, cardiopulmonary, and nervous systems can result in physical dysfunction, impaired performance, muscle weakness, and disuse-induced atrophy. Due to its well-documented anabolic potential, creatine monohydrate has been investigated as a supplemental agent to mitigate the loss of muscle mass and function in a variety of acute and chronic conditions. A review of the literature was conducted to assess the current state of knowledge regarding the effects of creatine supplementation on rehabilitation from immobilization and injury, neurodegenerative diseases, cardiopulmonary disease, and other muscular disorders. Several of the findings are encouraging, showcasing creatine's potential efficacy as a supplemental agent via preservation of muscle mass, strength, and physical function; however, the results are not consistent. For multiple diseases, only a few creatine studies with small sample sizes have been published, making it difficult to draw definitive conclusions. Rationale for discordant findings is further complicated by differences in disease pathologies, intervention protocols, creatine dosing and duration, and patient population. While creatine supplementation demonstrates promise as a therapeutic aid, more research is needed to fill gaps in knowledge within medical rehabilitation.


Asunto(s)
Creatina , Suplementos Dietéticos , Rehabilitación , Adolescente , Adulto , Niño , Creatina/farmacología , Creatina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Enfermedades Musculares/tratamiento farmacológico , Enfermedades Musculares/fisiopatología , Enfermedades Musculares/rehabilitación , Adulto Joven
7.
J Sports Sci ; 38(13): 1531-1538, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32252597

RESUMEN

We quantified the peak age of judokas during the World Championships (WC) and Olympic Games (OG) according to sex, weight category and competitive achievement and determined the relationship between competition year and athlete age. A retrospective study including 12,005 athletes who took part in the last 16 WC and 6 OG. Athletes were divided by sex, weight category and competitive achievement. Overall, females were younger than males, and older athletes competed at the OG compared to the WC. A weight category effect was also observed, with lighter athletes being younger than heavier athletes (p < 0.05). A competitive achievement effect was found for females, with athletes being defeated in the eliminatory phases being younger than those advancing further in the competitions (p < 0.05). Significant associations (p < 0.05) were shown between competition year and age category for males at the WC and for females at both the WC and OG. In general, lighter athletes are younger than heavier ones (p < 0.05). No difference in age was found  between males concerning their competitive achievement in WC and OG, whereas younger females are defeated in the eliminatory phases (p < 0.05).


Asunto(s)
Logro , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Artes Marciales/fisiología , Adulto , Factores de Edad , Peso Corporal , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores Sexuales , Adulto Joven
8.
J Autism Dev Disord ; 50(4): 1418-1424, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31848796

RESUMEN

To examine the preliminary efficacy of an 8-week judo program to promote moderate-to-vigorous physical activity (MVPA) and reduce sedentary behavior (SB) in youth with Autism Spectrum Disorder (ASD). Fourteen children diagnosed with ASD participated in a weekly judo program over a period of 8 weeks. Participants wore an Actigraph accelerometer to measure activity levels at baseline and post-judo. All 14 children attended at least 75% of the 8 judo classes. Percentage of time spent in daily MVPA (8% vs 4%, p = .05) increased following the intervention. A high rate of participation and an increase in time spent in MVPA was observed following the 8-week program. Further research to examine causal mechanisms is warranted.


Asunto(s)
Trastorno del Espectro Autista/rehabilitación , Terapia por Ejercicio/métodos , Promoción de la Salud/métodos , Artes Marciales , Adolescente , Niño , Ejercicio Físico , Femenino , Humanos , Masculino
9.
J Am Coll Nutr ; 38(2): 149-161, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30277420

RESUMEN

OBJECTIVE: The present study evaluated the effects of repeated-sprint training in normobaric hypoxia and ß-alanine supplementation (BA) on aerobic and anaerobic performance in recreationally active men. METHODS: Participants were randomly assigned to one of the following groups: normoxia/ß-alanine (NB, n = 11), normoxia/placebo (NP, n = 8), normobaric hypoxia/ß-alanine (HB, n = 10) and normobaric hypoxia/placebo (HP, n = 9). All participants completed 8 training sessions over 4 weeks on a cycle ergometer either in normobaric hypoxia (oxygen fraction: FiO2 = 14.2%) or normoxia (FiO2 = 20.9%). Participants were instructed to consume a daily dosage of 6.4 g of BA or placebo. Changes in performance in a graded exercise test, repeated-sprint test (RST), and 3-minute all-out test (3MT) were examined before and after training and supplementation. RESULTS: No between-group differences were observed for training volume or supplementation compliance. Anthropometric and hematological measures remained unchanged before and after intervention in all groups. A main effect of training condition was shown for oxygen consumption and power output at respiratory compensation point, average power output during the last sprint of the RST, heart rate recovery following the RST, and total work during the 3MT. These measures in the normobaric hypoxia groups were significantly (p < 0.05) higher than the normoxia groups, except for the heart rate recovery following the RST. A main effect of supplement was detected in anaerobic working capacity, with postintervention values in the BA groups being significantly (p < 0.05) higher than the placebo groups. CONCLUSIONS: Repeated-sprint training in hypoxia improved aerobic performance, exercise tolerance, cardiovascular recovery, and overall working capacity, while BA maintained the anaerobic working capacity. However, BA did not provide additional benefits with respect to attenuating fatigue or enhancing repeated-sprint performance.


Asunto(s)
Rendimiento Atlético/fisiología , Suplementos Dietéticos , Entrenamiento de Intervalos de Alta Intensidad/métodos , Hipoxia/fisiopatología , beta-Alanina/farmacología , Adulto , Ciclismo/fisiología , Prueba de Esfuerzo , Tolerancia al Ejercicio/efectos de los fármacos , Voluntarios Sanos , Humanos , Hipoxia/terapia , Masculino , Consumo de Oxígeno , Carrera/fisiología , Adulto Joven
10.
Amino Acids ; 51(1): 49-60, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30003336

RESUMEN

ß-alanine supplementation increases muscle carnosine content and improves anaerobic exercise performance by enhancing intracellular buffering capacity. ß-alanine ingestion in its traditional rapid-release formulation (RR) is associated with the symptoms of paresthesia. A sustained-release formulation (SR) of ß-alanine has been shown to circumvent paresthesia and extend the period of supply to muscle for carnosine synthesis. The purpose of this investigation was to compare 28 days of SR and RR formulations of ß-alanine (6 g day-1) on changes in carnosine content of the vastus lateralis and muscle fatigue. Thirty-nine recreationally active men and women were assigned to one of the three groups: SR, RR, or placebo (PLA). Participants supplementing with SR and RR formulations increased muscle carnosine content by 50.1% (3.87 mmol kg-1ww) and 37.9% (2.62 mmol kg-1ww), respectively. The change in muscle carnosine content in participants consuming SR was significantly different (p = 0.010) from those consuming PLA, but no significant difference was noted between RR and PLA (p = 0.077). Although participants ingesting SR experienced a 16.4% greater increase in muscle carnosine than RR, fatigue during maximal voluntary isometric contractions was significantly attenuated in both SR and RR compared to PLA (p = 0.002 and 0.024, respectively). Symptoms of paresthesia were significantly more frequent in RR compared to SR, the latter of which did not differ from PLA. Results of this study demonstrated that only participants consuming the SR formulation experienced a significant increase in muscle carnosine. Differences in the muscle carnosine response between these formulations may have practical significance for athletic populations in which small changes may have important implications on performance.


Asunto(s)
Carnosina/biosíntesis , Preparaciones de Acción Retardada/administración & dosificación , Suplementos Dietéticos , Músculo Esquelético/efectos de los fármacos , Parestesia/prevención & control , beta-Alanina/administración & dosificación , Adulto , Carnosina/agonistas , Método Doble Ciego , Esquema de Medicación , Ejercicio Físico , Femenino , Humanos , Contracción Isométrica/efectos de los fármacos , Masculino , Fatiga Muscular/efectos de los fármacos , Fatiga Muscular/fisiología , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Parestesia/metabolismo , Parestesia/fisiopatología
11.
J Strength Cond Res ; 33(8): 2241-2250, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29324576

RESUMEN

Carballeira, E, Morales, J, Fukuda, DH, Granada, ML, Carratalá-Deval, V, López Díaz de Durana, A, and Stout, JR. Intermittent cooling during Judo training in a warm/humid environment reduces autonomic and hormonal impact. J Strength Cond Res 33(8): 2241-2250, 2019-The purpose of this study was to identify the effects of superficial cooling on physiological responses while training in a warm, humid environment during an international Judo training camp. Sixteen judokas (8 women and 8 men) participated in the experiment. Four high-level women and 4 men were randomly assigned to wear a cooling vest (vest group [VG]) during the recovery periods within a training session (i.e., 8 bouts of 5-minute fighting with 5-minute rest) and up to 10 minutes after the session, whereas the remaining athletes in the control group (CG) trained without the use of any cooling aids. No differences between groups were reported in well-being before the session or in perceived fatigue after the session. The temperature was increased after the training session (p = 0.02) without significant differences between groups; however, CG demonstrated a moderate effect size (ES = 0.95, 90% confidence interval [CI] = 0.09-1.82; probability of superiority [PS] = 74.9%) in contrast to the small effect for VG (ES = 0.28, 90% CI = -0.55 to 1.11; PS = 57.9%). There were time × group interactions for heart rate variability (lnRMSSD) (p = 0.006; VG vs. CG, PS = 79.0%) and the dehydroepiandrosterone-cortisol ratio (DHEA/C ratio) (p = 0.04; VG vs. CG, PS = 99.9%). Vest group preserved the cardiac autonomic control (p > = 0.05; ES = -0.06, 90% CI = -0.88 to 0.76; PS = 51.7%) compared with the large decrement of CG (p < 0.05; ES = -1.18, 90% CI = -2.07 to -0.29; PS = 74.9%). Furthermore, VG showed an increase of DHEA/C (p = 0.002) from presession to postsession based on a moderate decrease of cortisol (p > = 0.05; ES = -0.67, 90% CI = -1.52 to 0.17; PS = 68.2%) with a concomitant small increase of DHEA (p > = 0.05; ES = 0.46, 90% CI = -0.38 to 1.29; PS = 62.7%). Conversely, the CG showed a moderate effect for increased DHEA and a small effect for increased cortisol after training. No significant interactions or main effects were shown for isometric handgrip values. Cooling vests diminished the cardiovascular strain and hormonal impact of the Judo training session in high-level athletes and may be considered for recovery purposes during exercise in warm/humid environments.


Asunto(s)
Frío , Calor , Humedad , Artes Marciales/fisiología , Adolescente , Adulto , Atletas , Temperatura Corporal , Ejercicio Físico/fisiología , Femenino , Fuerza de la Mano/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Percepción , Saliva/química , Adulto Joven
12.
Med Sci Sports Exerc ; 50(11): 2231-2241, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29957728

RESUMEN

PURPOSE: To examine the impact of polyphenol supplementation on the recruitment, mobilization, and activation of monocyte subsets after resistance exercise. METHODS: Thirty-eight recreationally active males (22.1 ± 3.1 yr; 173.9 ± 7.9 cm; 77.8 ± 14.5 kg) were assigned to 28 d of polyphenol blend (PPB) supplementation, placebo (PL), or control (CON). Blood samples were obtained before (PRE) postresistance exercise, immediately (IP) postresistance exercise, 1 h (1H) postresistance exercise, 5 h (5H) postresistance exercise, 24 h (24H) postresistance exercise, and 48 h (48H) postresistance exercise (PPB/PL) or rest (CON). Fine-needle biopsies were obtained from the vastus lateralis at PRE, 1H, 5H, and 48H. Circulating concentrations of macrophage chemoattractant protein-1 (MCP-1) and fractalkine, as well as intramuscular MCP-1 were analyzed via multiplex assay. Changes in the proportions and expression of CD11b on monocyte subsets were assessed via flow cytometry. RESULTS: Circulating MCP-1 increased in PPB and PL at IP with further increases at 5H. Intramuscular MCP-1 was increased at 1H, 5H, and 48H in all groups. Classical monocyte proportions were reduced in PPB and PL at IP, and increased at 1H. Nonclassical monocytes were increased in PPB and PL at IP, whereas intermediate monocytes were increased at IP, and reduced at 1H. Intermediate monocytes were increased in PPB at 24H and 48H. CD11b expression was reduced on PPB compared with PL and CON at PRE on intermediate and nonclassical monocytes. CONCLUSIONS: Resistance exercise may elicit selective mobilization of intermediate monocytes at 24H and 48H, which may be mediated by tissue damage. Additionally, polyphenol supplementation may suppress CD11b expression on monocyte subsets at rest.


Asunto(s)
Antioxidantes/administración & dosificación , Suplementos Dietéticos , Monocitos/metabolismo , Polifenoles/administración & dosificación , Músculo Cuádriceps/metabolismo , Entrenamiento de Fuerza , Antígeno CD11b/sangre , Quimiocina CCL2/sangre , Quimiocina CCL2/metabolismo , Quimiocina CX3CL1/sangre , Humanos , Antígeno de Macrófago-1/sangre , Masculino , Factores de Tiempo , Adulto Joven
13.
Physiol Rep ; 6(2)2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29380956

RESUMEN

The purpose of this study was to examine the effects of 28-days of supplementation with an aqueous proprietary polyphenol blend (PPB) sourced from Camellia sinensis on intramuscular apoptotic signaling following an acute lower-body resistance exercise protocol and subsequent recovery. Untrained males (n = 38, 21.8 ± 2.7 years, 173.4 ± 7.9 cm, 77.6 ± 14.6 kg) were randomized to PPB (n = 14), placebo (PL; n = 14) or control (CON; n = 10). Participants completed a lower-body resistance exercise protocol comprised of the squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis preexercise (PRE), 1-h (1HR), 5-h (5HR), and 48-h (48HR) post-resistance exercise. Apoptotic signaling pathways were quantified using multiplex signaling assay kits to quantify total proteins (Caspase 3, 8, 9) and markers of phosphorylation status (JNK, FADD, p53, BAD, Bcl-2). Changes in markers of muscle damage and intramuscular signaling were analyzed via separate repeated measures analysis of variance (ANOVA). Change in Bcl-2 phosphorylation at 1H was significantly greater in PL compared to CON (P = 0.001). BAD phosphorylation was significantly elevated at 5H in PL compared to PPB (P = 0.015) and CON (P = 0.006). The change in JNK phosphorylation was significantly greater in PPB (P = 0.009), and PL (P = 0.017) compared to CON at 1H, while the change for PL was elevated compared to CON at 5H (P = 0.002). A main effect was observed (P < 0.05) at 1H, 5H, and 48H for p53 and Caspase 8, with Caspase 3 and Caspase 9 elevated at 48H. These data indicate that chronic supplementation with PPB alters apoptotic signaling in skeletal muscle following acute muscle-damaging resistance exercise.


Asunto(s)
Suplementos Dietéticos , Músculo Esquelético/fisiología , Extractos Vegetales/farmacología , Polifenoles/farmacología , Entrenamiento de Fuerza , Apoptosis/fisiología , Humanos , Masculino , Adulto Joven
14.
Nutr Res ; 48: 16-25, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29246277

RESUMEN

ß-Alanine (BA) supplementation results in elevated intramuscular carnosine content, enhancing buffering capacity during intense exercise. Although men have greater muscle carnosine content than women, elevations still appear to occur despite high baseline levels. Recent research has suggested that BA supplementation may also reduce muscle l-histidine. Thus, the purpose of this investigation was to compare 28 days of BA (6 g·d-1) supplementation in men and women on performance and muscle carnosine, l-histidine, and BA. We hypothesized that supplementation would result in similar elevations in carnosine and performance between sexes and decrease l-histidine. Twenty-six men and women were assigned either BA or placebo (PLA). At baseline, a trend toward greater carnosine (P = .069) was observed in men, and intramuscular BA content was significantly (P ≤ .05) greater in men. Statistical analysis was performed using magnitude-based inferences. Changes in muscle carnosine were likely and very likely greater after BA supplementation compared with PLA in men and women, respectively, but changes were unclear between sexes (mean sex difference: 2.50 ± 4.30 mmol·kg-1 ww). The attenuation of exercise fatigue was likely greater in BA compared with PLA, but the change was unclear between sexes (mean sex difference: 14.0 ± 39.0 Nm). Changes in muscle BA following supplementation was unclear in men, likely elevated in women, but unclear between sexes (mean sex difference: 0.03 ± 0.42 mmol·kg-1 ww). Changes in muscle l-histidine were unclear in men and women, and unclear between sexes (mean sex difference: 0.09 ± 0.13 mmol·kg-1 ww). In conclusion, BA supplementation increased muscle carnosine and attenuated fatigue in men and women similarly but did not reduce muscle l-histidine.


Asunto(s)
Carnosina/metabolismo , Suplementos Dietéticos , Fatiga/tratamiento farmacológico , Histidina/metabolismo , Músculo Esquelético/efectos de los fármacos , beta-Alanina/administración & dosificación , Adulto , Ejercicio Físico , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo , Encuestas y Cuestionarios , Adulto Joven
15.
J Am Coll Nutr ; 36(8): 608-616, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28910200

RESUMEN

OBJECTIVE: ß-alanine (BA) is a nonproteogenic amino acid that combines with histidine to form carnosine. The amount taken orally in individual doses, however, is limited due to symptoms of paresthesia that are associated with higher doses. The use of a sustained-release formulation has been reported to reduce the symptoms of paresthesia, suggesting that a greater daily dose may be possible. The purpose of the present study was to determine whether increasing the daily dose of BA can result in a similar increase in muscle carnosine in a reduced time. METHODS: Eighteen men and twelve women were randomized into either a placebo (PLC), 6-g BA (6G), or 12-g BA (12G) groups. PLC and 6G were supplemented for 4 weeks, while 12G was supplemented for 2 weeks. A resting blood draw and muscle biopsy were obtained prior to (PRE) and following (POST) supplementation. Plasma and muscle metabolites were measured by high-performance liquid chromatography. The loss in peak torque (ΔPT) was calculated from maximal isometric contractions before and after 250 isokinetic kicks at 180°·sec-1 PRE and POST. RESULTS: Both 12G (p = 0.026) and 6G (p = 0.004) increased muscle carnosine compared to PLC. Plasma histidine was decreased from PRE to POST in 12G compared to PLC (p = 0.002) and 6G (p = 0.001), but no group x time interaction (p = 0.662) was observed for muscle histidine. No differences were observed for any hematological measure (e.g., complete blood counts) or in symptoms of paresthesia among the groups. Although no interaction was noted in ΔPT, a trend (p = 0.073) was observed. CONCLUSION: Results of this investigation indicate that a BA supplementation protocol of 12 g/d-1, using a sustained-release formulation, can accelerate the increase in carnosine content in skeletal muscle while attenuating paresthesia.


Asunto(s)
Carnosina/metabolismo , Suplementos Dietéticos , Músculo Esquelético/efectos de los fármacos , Fenómenos Fisiológicos en la Nutrición Deportiva , beta-Alanina/administración & dosificación , Adulto , Dieta , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Relación Dosis-Respuesta a Droga , Ejercicio Físico , Femenino , Histidina/sangre , Humanos , Masculino , Músculo Esquelético/metabolismo , Evaluación Nutricional , Parestesia/tratamiento farmacológico , Cooperación del Paciente , Encuestas y Cuestionarios , Adulto Joven , beta-Alanina/sangre
16.
Amino Acids ; 49(8): 1415-1426, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28555251

RESUMEN

Attenuating TNFα/TNFr1 signaling in monocytes has been proposed as a means of mitigating inflammation. The purpose of this study was to examine the effects of a milk protein supplement on TNFα and monocyte TNFr1 expression. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of myoglobin; tumor necrosis factor-alpha (TNFα); and expression of tumor necrosis factor receptor 1 (TNFr1) on classical, intermediate, and non-classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Plasma TNFα concentrations were "likely attenuated" (91.6% likelihood effect) from BL to 30P in the SUPP group compared with PL (d = 0.87; mean effect: 2.3 ± 2.4 pg mL-1). TNFr1 expressions on classical (75.9% likelihood effect) and intermediate (93.0% likelihood effect) monocytes were "likely attenuated" from BL to 2H in the SUPP group compared with PL (d = 0.67; mean effect: 510 ± 670 RFU, and d = 1.05; mean effect: 2500 ± 2300 RFU, respectively). TNFr1 expression on non-classical monocytes was "likely attenuated" (77.6% likelihood effect) from BL to 1H in the SUPP group compared with PL (d = 0.69; mean effect: 330 ± 430 RFU). Ingestion of a milk protein supplement immediately post-exercise appears to attenuate both plasma TNFα concentrations and TNFr1 expression on monocyte subpopulations in resistance-trained men.


Asunto(s)
Suplementos Dietéticos , Proteínas de la Leche/administración & dosificación , Monocitos/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Entrenamiento de Fuerza , Factor de Necrosis Tumoral alfa/sangre , Adulto , Células Cultivadas , Estudios Cruzados , Ingestión de Alimentos , Humanos , Inflamación/metabolismo , Inflamación/prevención & control , Masculino , Monocitos/citología , Adulto Joven
17.
J Strength Cond Res ; 31(3): 817-825, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27548785

RESUMEN

Sterkowicz-Przybycien, K, Miarka, B, and Fukuda, DH. Sex and weight category differences in time-motion analysis of elite judo athletes: implications for assessment and training. J Strength Cond Res 31(3): 817-825, 2017-The purpose of this investigation was to support training program development through the comparison of combat and pause phases during elite male and female judo competition in athletes of varying weight categories. A total of 1,411 video recorded judo matches between athletes who qualified for the 2012 Olympic Games were analyzed. Within the matches, 111,203 competitive situations were categorized as combat (with subphases of approach, gripping, attack, defense, and groundwork) or pause phases. Time-motion analysis data were compared between extra light, light, middle, and heavyweight categories for men and women. Median times varied between sex and weight category groups for individual combat (23.9-28.5 seconds), pause (4.0-8.8 seconds), and combat subphases (p ≤ 0.05). Sex-based differences in accumulated combat and combat subphase times were primarily found in the middleweight athletes. Heavyweight female athletes had longer accumulated groundwork and pause times, extra lightweight women had greater groundwork time, and both extra light and lightweight women had shorter accumulated attack times compared with their male counterparts. No differences between men and women were found for the time to complete an individual combat action; however, the pause phase and most of the combat subphases displayed differences. The lightest and heaviest judo athletes displayed unique characteristics compared with athletes in the other weight categories, particularly in the attack, defense, groundwork, and pause phases. These results have important implications related to training program design and support the need for the development of normative data for male and female judo athletes of varying weight categories.


Asunto(s)
Atletas , Peso Corporal , Artes Marciales/fisiología , Análisis y Desempeño de Tareas , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
18.
J Sports Med Phys Fitness ; 57(6): 872-878, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27054353

RESUMEN

BACKGROUND: This study aimed to analyze the acute effects of a judo training session on muscle strength, delayed-onset muscle soreness (DOMS), and serum creatine kinase (CK) activity. METHODS: Ten male judo athletes participated in this study and performed a 90-min traditional judo training session. The following measurements were performed before and 48 hours after the training: shoulder external/internal rotation isokinetic torque, countermovement jump (CMJ), DOMS, and blood draw for serum CK analysis. Student's t-test with significance level set at 5% and, effect size analysis were used. RESULTS: Significant reduction was found in jump height in the CMJ after the training session (2.9%; moderate effect; P=0.02). No significant differences were observed in any of the measures of shoulder external/internal rotation isokinetic torque (P>0.05). An increase of the serum CK (49.4%; moderate effect; P=0.01) and DOMS (20.6%; large effect; P=0.003) were noted after the training session when compared to baseline. CONCLUSIONS: Judo training session resulted in increased serum CK activity, and muscle soreness. The decrease of CMJ performance indicates impairment in the lower-limbs muscle power production. However, the lack of difference of shoulder external/internal rotation torque before and 48 hours after the training session may indicate that the interval was enough to recover the upper-limbs strength in judokas of this study. These markers of muscle damage can be used to control muscle adaptation progress and to avoid sports-related disorders of athletes with similar characteristics to those evaluated in this study.


Asunto(s)
Creatina Quinasa/sangre , Ejercicio Físico/fisiología , Artes Marciales/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Mialgia/etiología , Adulto , Biomarcadores/sangre , Humanos , Masculino , Rango del Movimiento Articular , Articulación del Hombro , Torque , Adulto Joven
19.
Motor Control ; 21(4): 373-389, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27736310

RESUMEN

This study examined the effect of a 10-week introductory judo course on postural control during a bilateral reactionary gripping task using different stance conditions. A total of 20 volunteers were divided into experimental (JDO) and control (CON) groups. Countermovement jump was measured and center of pressure variables were evaluated while performing a bilateral reactionary gripping task under different stance conditions during pre- and posttesting. No interactions were observed for the center of pressure variables (p > .05), while both countermovement jump power (+165.4 W; p = .036) and height (+3.5 cm; p = .018) significantly improved in the JDO group following the 10-week course. Results indicate that 10 weeks of an introductory judo course has no effect on postural control while performing a bilateral reactionary gripping task using different stance conditions.


Asunto(s)
Ejercicio Físico/fisiología , Fuerza de la Mano/fisiología , Artes Marciales/fisiología , Equilibrio Postural/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
20.
Motor Control ; 21(4): 390-412, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27736312

RESUMEN

The purpose of the present study was to create a probabilistic neural network to clarify the understanding of movement patterns in international judo competitions by gender. Analysis of 773 male and 638 female bouts was utilized to identify movements during the approach, gripping, attack (including biomechanical designations), groundwork, defense, and pause phases. Probabilistic neural network and chi-square (χ2) tests modeled and compared frequencies (p ≤ .05). Women (mean [interquartile range]: 9.9 [4; 14]) attacked more than men (7.0 [3; 10]) while attempting a greater number of arm/leg lever (women: 2.7 [1; 6]; men: 4.0 [0; 4]) and trunk/leg lever (women: 0.8 [0; 1]; men: 2.4 [0; 4]) techniques but fewer maximal length-moment arm techniques (women: 0.7 [0; 1]; men: 1.0 [0; 2]). Male athletes displayed one-handed gripping of the back and sleeve, whereas female athletes executed a greater number of groundwork techniques. An optimized probabilistic neural network model, using patterns from the gripping, attack, groundwork, and pause phases, produced an overall prediction accuracy of 76% for discrimination between men and women.


Asunto(s)
Artes Marciales/fisiología , Movimiento/fisiología , Adulto , Femenino , Humanos , Masculino , Factores Sexuales
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