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1.
Int J Sports Physiol Perform ; 18(4): 347-353, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36780901

RESUMEN

PURPOSE: To examine the effects of acute curcumin (CURC) supplementation on recovery from a soccer match in male professional players. METHODS: In a randomized, placebo-controlled, crossover design, 11 players from the under-23 team of an English Premier League club (age 19 [1] y, body mass 79.4 [7.9] kg, height 180.8 [5.7] cm) consumed 500 mg of CURC or a control (medium-chain triglycerides) immediately and 12 and 36 hours after a 90-minute match. Countermovement jump height (CMJ), reactive strength index (RSI), delayed-onset muscle soreness (DOMS, 0-200 mm), and subjective well-being were measured before and 12, 36, and 60 hours postmatch. Global positioning systems measured external load during matches, and dietary intake was recorded across the testing period. RESULTS: External load and dietary intake did not differ between conditions (P ≥ .246). CURC attenuated deficits in CMJ (P ≤ .004) and RSI (P ≤ .001) and reduced DOMS (P ≤ .004) at all postmatch time points (except 60 h post for RSI). The greatest difference between control and CURC was 12 hours post for CMJ (P < .001, 1.91 [4.40] cm, 95% CI, 1.25 to 2.57, g = 0.36) and RSI (P = .003, 0.40 [0.41] AU, 95% CI, 0.17 to 0.63, g = 0.90) and 36 hours post for DOMS (P < .001, 47 [23] mm, 95% CI, -67 to -27, g = 2.12). CONCLUSIONS: CURC intake <36 hours after a soccer match attenuated DOMS and muscle function deficits, suggesting that CURC may aid recovery in professional male soccer players.


Asunto(s)
Rendimiento Atlético , Curcumina , Fútbol , Adulto , Humanos , Masculino , Adulto Joven , Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Músculos , Mialgia/prevención & control , Fútbol/fisiología , Estudios Cruzados
2.
J Int Soc Sports Nutr ; 18(1): 42, 2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-34090451

RESUMEN

OBJECTIVE: Systemic elevations in pro-inflammatory cytokines are a marker of non-functional over reaching, and betaine has been shown to reduce the secretion of pro-inflammatory cytokines in vitro. The aim of this study was to investigate the effects of betaine supplementation on tumor necrosis factor alpha (TNF-α), interleukins-1 beta (IL-1ß), - 6 (IL-6) and the complete blood cell (CBC) count in professional youth soccer players during a competitive season. METHODS: Twenty-nine soccer players (age, 15.5 ± 0.3 years) were randomly divided into two groups based on playing position: betaine group (BG, n = 14, 2 g/day) or placebo group (PG, n = 15). During the 14-week period, training load was matched and well-being indicators were monitored daily. The aforementioned cytokines and CBC were assessed at pre- (P1), mid- (P2), and post- (P3) season. RESULTS: Significant (p < 0.05) group x time interactions were found for TNF-α, IL-1ß, and IL-6. These variables were lower in the BG at P2 and P3 compared to P1, while IL-1ß was greater in the PG at P3 compared to P1 (p = 0.033). The CBC count analysis showed there was significant group by time interactions for white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), and mean corpuscular hemoglobin concentration (MCHC). WBC demonstrated increases at P3 compared to P2 in PG (p = 0.034); RBC was less at P3 compared to P1 in BG (p = 0.020); Hb was greater at P2 compared to P1, whilst it was less at P3 compared to P3 for both groups. MCHC was greater at P3 and P2 compared to P1 in BG, whereas MCHC was significantly lower at P3 compared to P2 in the PG (p = 0.003). CONCLUSION: The results confirmed that 14 weeks of betaine supplementation prevented an increase in pro-inflammatory cytokines and WBC counts. It seems that betaine supplementation may be a useful nutritional strategy to regulate the immune response during a fatiguing soccer season.


Asunto(s)
Betaína/administración & dosificación , Conducta Competitiva/fisiología , Citocinas/sangre , Suplementos Dietéticos , Fútbol/fisiología , Adolescente , Biomarcadores/sangre , Recuento de Células Sanguíneas , Método Doble Ciego , Índices de Eritrocitos , Hemoglobinometría , Humanos , Interleucina-1beta/sangre , Interleucina-6/sangre , Factor de Necrosis Tumoral alfa/sangre
3.
J Int Soc Sports Nutr ; 18(1): 40, 2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34044858

RESUMEN

BACKGROUND: Carbohydrate (CHO) ingestion enhances exercise performance; however, the efficacy of CHO intake on repeated bouts of exercise simulating a taekwondo tournament is unknown. Therefore, the purpose was to compare the effects of two different doses of CHO on a sports-specific kicking test during a simulated taekwondo tournament compared to placebo (PLA). METHODS: In a double-blind, randomized-placebo controlled, cross-over trial, eleven junior male professional taekwondo athletes (age: 16 ± 0.8 years, body mass: 55.3 ± 7.3 kg) ingested one of three solutions: (i) high dose (C45): 45 g of CHO (60 g∙h- 1), (ii) low dose (C22.5): 22.5 g of CHO (30 g∙h- 1; both solutions containing 2:1 glucose:fructose), or a PLA immediately following each kicking test. The kicking test was repeated 5 times, separated by 45 mins of rest, simulating a typical taekwondo competition day. Ratings of perceived exertion (RPE) and gastrointestinal discomfort (GI) scores were collected immediately after, and blood glucose before each test. RESULTS: The results revealed that C45 and C22.5 did not improve total, successful, or percentage of successful kicks compared to PLA (p > 0.05). Blood glucose was significantly higher following both CHO conditions compared with PLA across all five tests (p < 0.05). There were no differences between treatments or across tests for RPE (p > 0.05). CONCLUSION: CHO intake, independent of the dose, did not alter taekwondo kick performance during a simulated taekwondo tournament.


Asunto(s)
Rendimiento Atlético/fisiología , Sacarosa en la Dieta/administración & dosificación , Fructosa/administración & dosificación , Artes Marciales/fisiología , Adolescente , Bebidas , Glucemia/metabolismo , Índice de Masa Corporal , Conducta Competitiva/fisiología , Estudios Cruzados , Sacarosa en la Dieta/efectos adversos , Método Doble Ciego , Fructosa/efectos adversos , Pirosis/etiología , Humanos , Masculino , Percepción/fisiología , Esfuerzo Físico/fisiología
4.
PLoS One ; 16(5): e0251266, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33970947

RESUMEN

The aim of this study was to quantify typical training load and periodisation practices of MMA athletes. MMA competitors (n = 14; age = 22.4 ± 4.4 years; body mass = 71.3 ± 7.7 kg; stature = 171 ±9.9 cm) were observed during training for 8 consecutive weeks without intervention. Seven athletes were training for competitive bouts whilst the remaining 7 were not. Daily training duration, intensity (RPE), load (sRPE and segRPE), fatigue (short questionnaire of fatigue) and body region soreness (CR10 scale) were recorded. Using Bayesian analyses (BF10≥3), data demonstrate that training duration (weekly mean range = 3.9-5.3 hours), sRPE (weekly mean range = 1,287-1,791 AU), strain (weekly mean range = 1,143-1,819 AU), monotony (weekly mean range = 0.63-0.83 AU), fatigue (weekly mean range = 16-20 AU) and soreness did not change within or between weeks. Between weeks monotony (2.3 ± 0.7 AU) supported little variance in weekly training load. There were no differences in any variable between participants who competed and those who did not with the except of the final week before the bout, where an abrupt step taper occurred leading to no between group differences in fatigue. Training intensity distribution corresponding to high, moderate and low was 20, 33 and 47%, respectively. Striking drills accounted for the largest portion of weekly training time (20-32%), with MMA sparring the least (2-7%). Only striking sparring and wrestling sparring displayed statistical weekly differences in duration or load. Athletes reported MMA sparring and wrestling sparring as high intensity (RPE≥7), BJJ sparring, striking sparring and wrestling drills as moderate intensity (RPE 5-6), and striking drills and BJJ drills as low intensity (RPE≤4). We conclude that periodisation of training load was largely absent in this cohort of MMA athletes, as is the case within and between weekly microcycles.


Asunto(s)
Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Ejercicio Físico/fisiología , Artes Marciales/fisiología , Esfuerzo Físico/fisiología , Estrés Fisiológico/fisiología , Adolescente , Adulto , Teorema de Bayes , Femenino , Humanos , Masculino , Adulto Joven
5.
J Int Soc Sports Nutr ; 18(1): 23, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33726784

RESUMEN

BACKGROUND: Soccer-specific speed-endurance training induces short-term neuromuscular fatigue and performance deterioration over a 72-h recovery period, associated with elevated markers of exercise-induced muscle damage. We compared the effects of whey vs. soy protein supplementation on field activity, performance, muscle damage and redox responses following speed-endurance training in soccer players. METHODS: Ten well-trained, male soccer players completed three speed-endurance training trials, receiving whey protein (WP), soy protein (SP) or an isoenergetic placebo (PL; maltodextrin) according to a randomized, double-blind, crossover, repeated-measures design. A pre-loading period was applied in each trial during which protein supplementation was individually adjusted to reach a total protein intake of 1.5 g/kg/day, whereas in PL protein intake was adjusted at 0.8-1 g/kg/day. Following pre-loading, two speed-endurance training sessions (1 and 2) were performed 1 day apart, over a 3-day experimental period. During each session, field activity and heart rate were continuously monitored using global positioning system and heart rate monitors, respectively. Performance (isokinetic strength of knee extensors and flexors, maximal voluntary isometric contraction, speed, repeated sprint ability, countermovement jump), muscle damage (delayed-onset of muscle soreness, creatine kinase activity) and redox status (glutathione, total antioxidant capacity, protein carbonyls) were evaluated at baseline (pre), following pre-loading (post-load), and during recovery from speed-endurance training. RESULTS: High-intensity and high-speed running decreased (P ≤ 0.05) during speed-endurance training in all trials, but WP and SP mitigated this response. Isokinetic strength, maximal voluntary isometric contraction, 30-m speed, repeated sprint ability and countermovement jump performance were similarly deteriorated during recovery following speed-endurance training in all trials (P ≤ 0.05). 10 m speed was impaired at 24 h only in PL. Delayed-onset of muscle soreness, creatine kinase, total antioxidant capacity and protein carbonyls increased and glutathione decreased equally among trials following speed-endurance training (P ≤ 0.05), with SP inducing a faster recovery of protein carbonyls only at 48 h (P ≤ 0.05) compared to WP and PL. CONCLUSIONS: In conclusion, increasing daily protein intake to 1.5 g/kg through ingestion of either whey or soy protein supplements mitigates field performance deterioration during successive speed-endurance training sessions without affecting exercise-induced muscle damage and redox status markers. TRIAL REGISTRATION: Name of the registry: clinicaltrials.gov. TRIAL REGISTRATION: NCT03753321 . Date of registration: 12/10/2018.


Asunto(s)
Rendimiento Atlético/fisiología , Suplementos Dietéticos , Entrenamiento Aeróbico , Mialgia/prevención & control , Fútbol/fisiología , Proteínas de Soja/administración & dosificación , Proteína de Suero de Leche/administración & dosificación , Antioxidantes/metabolismo , Conducta Competitiva/fisiología , Creatina Quinasa/sangre , Estudios Cruzados , Método Doble Ciego , Glutatión/sangre , Humanos , Masculino , Fatiga Muscular/fisiología , Músculo Esquelético/lesiones , Músculo Esquelético/metabolismo , Oxidación-Reducción , Carbonilación Proteica , Adulto Joven
6.
Curr Sports Med Rep ; 20(2): 87-91, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33560032

RESUMEN

ABSTRACT: Triathlon is a popular sport among recreational and competitive athletes. As triathletes compete in races ranging from 16 to 140.6 miles and train in three disciplines simultaneously, it is difficult to identify injury risk factors. The aim of this study was to evaluate characteristics of a group of recreational triathletes regarding their medical history, training regimen, and injuries. Thirty-four triathletes completed this survey. We found a wide range of body types, training habits, and lifestyle characteristics. As in previous studies, we found a high rate of injuries in our surveyed triathletes. Injury rates were higher in athletes who had completed a longer race and those who reported higher training times per week. Additionally, many individuals have medical problems, use a variety of supplements, and follow specific dietary restrictions, which need to be considered in addition to training when assessing injury risk and recovery from injury.


Asunto(s)
Ciclismo/lesiones , Conducta Competitiva/fisiología , Estilo de Vida , Acondicionamiento Físico Humano , Carrera/lesiones , Natación/lesiones , Adulto , Anciano , Índice de Masa Corporal , Dieta , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores de Tiempo , Adulto Joven
7.
J Sci Med Sport ; 24(2): 195-199, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32847731

RESUMEN

Probiotic supplementation may offer team sport athletes a range of benefits beyond the immune and gastrointestinal systems. OBJECTIVES: To examine the effects of a probiotic formulation on perceptual markers of sleep quality and quantity, and muscle soreness, leg heaviness and motivation in elite rugby union athletes. METHODS: A double-blind randomised controlled trial involving 19 elite male rugby athletes was conducted over 17 weeks encompassing both domestic and international competition. Psychometric variables and salivary biomarkers were assessed twice a week. Athletes were assigned either a daily probiotic (Ultrabiotic 60™) and Saccharomyces boulardii (during international competition) or a placebo. Associations between psychometric scores for perceptual and salivary biomarkers of sleep (melatonin) and inflammation C-reactive protein (CRP) were investigated. RESULTS: Muscle soreness was ∼0.5 units lower (F(1, 343)=42.646, p<0.0001) and leg heaviness scores ∼0.7 units lower (F(1, 334)=28.990, p<0.0001) in the probiotic group compared to the placebo group. Across both groups, as self-reported muscle soreness scores and salivary CRP concentrations increased, sleep quantity, quality and motivation scores decreased. Conversely as muscle soreness scores and CRP decreased, sleep quantity and quality, and motivation scores improved. CONCLUSIONS: A long-term programme of probiotic supplementation in international-level rugby union players may yield favourable effects on self-reported muscle soreness and sleep quality associated with muscle soreness during training and competitions.


Asunto(s)
Rendimiento Atlético/fisiología , Fútbol Americano/fisiología , Mialgia/prevención & control , Probióticos/administración & dosificación , Sueño/fisiología , Adulto , Rendimiento Atlético/psicología , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Conducta Competitiva/fisiología , Método Doble Ciego , Fútbol Americano/lesiones , Fútbol Americano/psicología , Humanos , Pierna/fisiología , Masculino , Melatonina/metabolismo , Motivación , Psicometría , Saliva/metabolismo , Autoinforme , Adulto Joven
8.
Scand J Med Sci Sports ; 31(1): 4-20, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32969103

RESUMEN

Handcycling is a mode of mobility, and sport format within Para-cycling, for those with a lower limb impairment. The exercise modality has been researched extensively in the rehabilitation setting. However, there is an emerging body of evidence detailing the physiological responses to handcycling in the competitive sport domain. Competitive handcyclists utilize equipment that is vastly disparate to that used for rehabilitation or recreation. Furthermore, the transferability of findings from early handcycling research to current international athletes regarding physiological profiles is severely limited. This narrative review aims to map the landscape within handcycling research and document the growing interest at the elite end of the exercise spectrum. From 58 experimental/case studies and four doctoral theses, we provide accounts of the aerobic capacity of handcyclists and the influence training status plays; present research regarding the physiological responses to handcycling performance, including tests of sprint performance; and discuss the finite information on handcyclists' training habits and efficacy of bespoke interventions. Furthermore, given the wide variety of protocols employed and participants recruited previously, we present considerations for the interpretation of existing research and recommendations for future work, all with a focus on competitive sport. The majority of studies (n = 21) reported aerobic capacity, detailing peak rates of oxygen uptake and power output, with values >3.0 L min-1 and 240 W shown in trained, male H3-H4 classification athletes. Knowledge, though, is lacking for other classifications and female athletes. Similarly, little research is available concerning sprint performance with only one from eight studies recruiting athletes with an impairment.


Asunto(s)
Ciclismo/fisiología , Conducta Competitiva/fisiología , Deportes para Personas con Discapacidad/fisiología , Rendimiento Atlético/fisiología , Regulación de la Temperatura Corporal/fisiología , Suplementos Dietéticos , Prueba de Esfuerzo , Humanos , Músculo Esquelético/fisiología , Consumo de Oxígeno , Acondicionamiento Físico Humano/fisiología , Equipo Deportivo
9.
Br J Sports Med ; 55(8): 416, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33097528

RESUMEN

Football is a global game which is constantly evolving, showing substantial increases in physical and technical demands. Nutrition plays a valuable integrated role in optimising performance of elite players during training and match-play, and maintaining their overall health throughout the season. An evidence-based approach to nutrition emphasising, a 'food first' philosophy (ie, food over supplements), is fundamental to ensure effective player support. This requires relevant scientific evidence to be applied according to the constraints of what is practical and feasible in the football setting. The science underpinning sports nutrition is evolving fast, and practitioners must be alert to new developments. In response to these developments, the Union of European Football Associations (UEFA) has gathered experts in applied sports nutrition research as well as practitioners working with elite football clubs and national associations/federations to issue an expert statement on a range of topics relevant to elite football nutrition: (1) match day nutrition, (2) training day nutrition, (3) body composition, (4) stressful environments and travel, (5) cultural diversity and dietary considerations, (6) dietary supplements, (7) rehabilitation, (8) referees and (9) junior high-level players. The expert group provide a narrative synthesis of the scientific background relating to these topics based on their knowledge and experience of the scientific research literature, as well as practical experience of applying knowledge within an elite sports setting. Our intention is to provide readers with content to help drive their own practical recommendations. In addition, to provide guidance to applied researchers where to focus future efforts.


Asunto(s)
Rendimiento Atlético/fisiología , Dieta Saludable , Política Nutricional , Fútbol/fisiología , Traumatismos en Atletas/rehabilitación , Composición Corporal , Conducta Competitiva/fisiología , Diversidad Cultural , Suplementos Dietéticos , Ambiente , Femenino , Humanos , Masculino , Necesidades Nutricionales , Acondicionamiento Físico Humano/fisiología , Viaje
10.
Int J Sport Nutr Exerc Metab ; 31(1): 73-89, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33321472

RESUMEN

Professional rugby league (RL) football is a contact sport involving repeated collisions and high-intensity efforts; both training and competition involve high energy expenditure. The present review summarizes and critiques the available literature relating the physiological demands of RL to nutritional requirements and considers potential ergogenic supplements that could improve players' physical capacity, health, and recovery during the preparatory and competition phases of a season. Although there may not be enough data to provide RL-specific recommendations, the available data suggest that players may require approximately 6-8 g·kg-1·day-1 carbohydrate, 1.6-2.6 g·kg-1·day-1 protein, and 0.7-2.2 g·kg-1·day-1 fat, provided that the latter also falls within 20-35% of total energy intake. Competition nutrition should maximize glycogen availability by consuming 1-4 g/kg carbohydrate (∼80-320 g) plus 0.25 g/kg (∼20-30 g) protein, 1-4 hr preexercise for 80-120 kg players. Carbohydrate intakes of approximately 80-180 g (1.0-1.5 g/kg) plus 20-67 g protein (0.25-0.55 g/kg) 0-2 hr postexercise will optimize glycogen resynthesis and muscle protein synthesis. Supplements that potentially improve performance, recovery, and adaptation include low to moderate dosages of caffeine (3-6 mg/kg) and ∼300 mg polyphenols consumed ∼1 hr preexercise, creatine monohydrate "loading" (0.3 g·kg-1·day-1) and/or maintenance (3-5 g/day), and beta-alanine (65-80 mg·kg-1·day-1). Future research should quantify energy expenditures in young, professional male RL players before constructing recommendations.


Asunto(s)
Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Fútbol Americano/fisiología , Necesidades Nutricionales , Adaptación Fisiológica , Adolescente , Suplementos Dietéticos , Metabolismo Energético , Humanos , Masculino , Estado Nutricional , Sustancias para Mejorar el Rendimiento , Adulto Joven
11.
J Int Soc Sports Nutr ; 17(1): 51, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-33087145

RESUMEN

BACKGROUND: Fish oils were studied as ergogenic aids in a number of mixed physical trial designs showing promising results. However, the heterogeneous purity of the studied supplements, combined with the variety of physical tests employed call for more studies to confirm these findings, ideally with standardised supplements. Our aim was to test a supplement highly concentrated in DHA (DHA:EPA ratio equal to approximately 8:1) on a maximal cycling test to elucidate performance improvements mainly due to DHA. METHODS: A double-blind, placebo controlled, randomised balanced, parallel design, in competitive amateur cyclists was employed. They were all male, older than 18 years old, with training routine of 2 to 4 sessions per week lasting at least one hour each. A ramp cycling test to exhaustion with a subsequent 5 min recovery phase was employed before and after treatment to analyse aerobic metabolism and lactate clearance after the bout. After 30 days of supplementation with 975 mg of re-esterified DHA, the thirty-eight cyclist who completed the study were finally included for statistical analysis. RESULTS: Mean power output at ventilatory threshold 2 (VT2) improved after DHA supplementation both as absolute (△DHA versus △PLA: 6.33-26.54 Watts; CI 95%) and relative (p=0.006) values, paralleled with higher oxygen consumption at VT2 both for absolute (DHA 2729.4 ±304.5, 3045.9 ±335.0; PLA 2792.3 ±339.5, 2845.5 ±357.1; ml·min-1 baseline versus post p=0.025) and relative values (DHA 36.6 ±5.0, 41.2 ±5.4; PLA 37.2 ±5.7, 38.1 ±5.2; ml·kg-1·min-1 baseline versus post p=0.024). Heart rate recovery rate improved during the recovery phase in the DHA group compared to PLA (p=0.005). CONCLUSION: DHA is capable of improving mean power output at the ventilatory threshold 2 (anaerobic ventilatory threshold) in amateur competitive cyclists. It is unclear if these findings are the result of the specific DHA supplement blend or another factor.


Asunto(s)
Umbral Anaerobio/fisiología , Rendimiento Atlético/fisiología , Ciclismo/fisiología , Conducta Competitiva/fisiología , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Sustancias para Mejorar el Rendimiento/administración & dosificación , Adulto , Ácidos Docosahexaenoicos/metabolismo , Método Doble Ciego , Esterificación , Frecuencia Cardíaca , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno , Sustancias para Mejorar el Rendimiento/metabolismo
12.
Nutrients ; 12(9)2020 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-32932611

RESUMEN

Athletes use different combinations of weight loss methods during competition preparation. The aim of this study was to identify and characterize pre-competition weight loss models, which describe these combinations. The second aim was to determine if any existing model pose a higher risk of severe dehydration and whether any of the models could be continued as a lower-risk option. The third aim was to explore whether athletes who used different weight management strategies could be differentiated based on age, sex, training experience or anthropometric parameters. Study participants were randomly selected from Olympic taekwondo competitors and 192 athletes were enrolled. Active (47% weight-reducing athletes), passive (31%) and extreme (22%) models have been described. In the extreme model, athletes combined the highest number of different weight loss methods (3.9 ± 0.9 methods vs. 2.4 ± 0.9 in active and 1.5 ± 0.6 in passive), reduced significantly more body mass than others (6.7 ± 3.5% body mass vs. 4.3 ± 1.9% and 4.5 ± 2.4%; p < 0.01) and all of them used methods with the highest risk of severe dehydration. The active and passive models could be continued as a lower-risk option, if athletes do not combine dehydrating methods and do not prolong the low energy availability phase. The extreme model carried the highest risk of severe dehydration. Every fifth weight-reducing taekwondo athlete may have been exposed to the adverse effects of acute weight loss. Taekwondo athletes, regardless of age, sex, training experience and anthropometric parameters, lose weight before the competition and those characteristics do not differentiate them between models.


Asunto(s)
Conducta Competitiva/fisiología , Deshidratación/etiología , Artes Marciales/fisiología , Pérdida de Peso/fisiología , Adolescente , Antropometría , Atletas , Niño , Análisis por Conglomerados , Femenino , Humanos , Masculino , Polonia , Factores de Riesgo , Adulto Joven
13.
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
14.
Philos Trans R Soc Lond B Biol Sci ; 375(1800): 20190267, 2020 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-32306874

RESUMEN

Dominance hierarchy is often established via repeated agonistic encounters where consistent winners are considered dominant. Human body odour contains cues to psychological dominance and competition, but it is not known whether competition outcome (a marker of a change in dominance hierarchy) affects the hedonic quality of human axillary odour. Therefore, we investigated the effect of winning and losing on odour quality. We collected odour samples from Mixed Martial Arts fighters approximately 1 h before and immediately after a match. Raters then assessed samples for pleasantness, attractiveness, masculinity and intensity. We also obtained data on donors' affective state and cortisol and testosterone levels, since these are known to be associated with competition and body odour quality. Perceived body odour pleasantness, attractiveness and intensity significantly decreased while masculinity increased after a match irrespective of the outcome. Nonetheless, losing a match affected the pleasantness of body odour more profoundly, though bordering formal level of significance. Moreover, a path analysis revealed that match loss led to a decrease in odour attractiveness, which was mediated by participants' negative affective states. Our study suggests that physical competition and to some extent also its outcome affect the perceived quality of human body odour in specific real-life settings, thus providing cues to dominance-related characteristics. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.


Asunto(s)
Conducta Competitiva/fisiología , Odorantes/análisis , Percepción Olfatoria , Olfato , Adulto , República Checa , Humanos , Hidrocortisona/sangre , Masculino , Artes Marciales , Testosterona/sangre , Adulto Joven
15.
J Sports Sci ; 38(7): 795-800, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32122273

RESUMEN

Mouth rinsing has been proposed as a strategy to minimize performance decrements during Ramadan. We investigated the effect of 4 weeks of Ramadan on kicking performance in 27 Taekwondo athletes performing weekly Taekwondo Anaerobic Intermittent Kick Tests (TAIKT). The effects of a placebo, 6.4% glucose and 6-mg/kg caffeine mouth rinses on TAIKT performance and perceived exertion were investigated before, during weekly training sessions, and after Ramadan in a counterbalanced, crossover design. Ramadan had a significant negative impact on the percentage of successful kicks in Week 1 of Ramadan (pre: 76.7±0.4%, Week 1: 69.9±3.2%). The percentage of successful kicks was significantly greater in the caffeine mouth rinse condition compared to the glucose and placebo conditions during the first 3 weeks of Ramadan (caffeine: 38.3±6.8%, glucose: 36.4±6.9%, placebo: 36.0±6.5%). Caffeine decreased perceived exertion during Ramadan (0.74-1.15 AU, p>0.05). Our results showed that Ramadan had a significant negative effect on repeated high-intensity kicking efforts that should be considered when training and competing. Additionally, there were significant positive effects of a caffeine mouth rinse in a sport-specific test. These data suggest that athletes can consider mouth rinsing as a strategy to enhance performance when undertaking training or competition during a period of privation.


Asunto(s)
Rendimiento Atlético/fisiología , Cafeína/administración & dosificación , Azúcares de la Dieta/administración & dosificación , Ayuno/fisiología , Islamismo , Artes Marciales/fisiología , Antisépticos Bucales , Adolescente , Adulto , Conducta Competitiva/fisiología , Estudios Cruzados , Femenino , Humanos , Masculino , Percepción/fisiología , Acondicionamiento Físico Humano , Esfuerzo Físico/fisiología , Adulto Joven
16.
Int J Sports Physiol Perform ; 15(6): 868-873, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32150724

RESUMEN

OBJECTIVE: To assess the discriminative ability of several fitness dimensions and anthropometric attributes for forecasting competitive success in female karate athletes. METHODS: Fitness and anthropometric data from 98 female junior karatekas obtained during the training camps of the Spanish National Karate Federation between 1999 and 2012 were used. Binary logistic-regression models were built to ascertain whether the set of fitness and anthropometric variables could predict future sporting-performance levels. For this purpose, participants were classified as elite (medalist in World or European Championships in the senior category) or subelite (at least a medalist in Spanish National Championships in cadet or junior but not included in the elite group), according to the results achieved up to 2019. RESULTS: Participants who were subsequently classified as elite karatekas showed significant differences in agility, upper- and lower-body muscle power, and general fitness in comparison with those who were classified as subelite in the senior category. A total of 57 junior female karatekas who were subsequently classified as elite (7) or subelite (50) were included in the binary logistic-regression analysis. Resultant models showed significant capacity to predict karate performance. CONCLUSIONS: Assessing physical fitness in junior categories can be a useful resource to determine future karate success. Coaches in this sport should pay special attention to the levels of muscle power and agility shown by their athletes, as both fitness dimensions could be indicators of future sportive success.


Asunto(s)
Rendimiento Atlético/fisiología , Artes Marciales/fisiología , Aptitud Física/fisiología , Adolescente , Distribución de la Grasa Corporal , Estatura , Índice de Masa Corporal , Peso Corporal , Conducta Competitiva/fisiología , Femenino , Humanos , Fuerza Muscular/fisiología
17.
J Sci Med Sport ; 23(5): 512-518, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31843442

RESUMEN

OBJECTIVE: Investigate the acute effects of repeated combat sports matches on vertical jump and handgrip strength performance in grappling and striking modalities. DESIGN: Systematic review. METHODS: PubMed, Scopus, and Web of Science databases were searched. The following eligibility criteria for selecting studies were adopted: Population: Combat sports athletes; Intervention: Official or simulated matches; Comparator: Baseline versus after-matches performance; Outcome: Vertical jump and/or handgrip strength performance. PROSPERO: CRD42019129264 RESULTS: The systematic search resulted in 13 studies, including Brazilian jiu-jitsu, Greco-Roman, judo, taekwondo, and wrestling (freestyle and Greco-Roman) modalities, and a diverse number of repeated matches (i.e. 1-5). None of the studies adopted a randomized and controlled design and, consequently, none of them was classified as high quality. Brazilian jiu-jitsu and freestyle wrestling athletes presented an earlier onset of fatigue in upper and lower limbs, while judo and Greco Roman wrestling presented a later onset, from the third match. In taekwondo athletes, no fatigue was observed in the lower limbs, while handgrip strength decreased. However, studies have reported unclear data regarding the time-course of lower and upper limbs' fatigue following repeated matches in taekwondo. CONCLUSION: Both upper and lower limbs performance were affected after repeated matches in grappling combat sports when assessed by handgrip strength and vertical jump performance. In taekwondo, the studies have shown unclear results concerning the effects of repeated matches on upper and lower limb performance. There is a lack of studies classified as high-quality and investigations into the neuromuscular mechanisms underpinning fatigue after the repeated matches.


Asunto(s)
Rendimiento Atlético/fisiología , Conducta Competitiva/fisiología , Fatiga/fisiopatología , Fuerza de la Mano , Artes Marciales/fisiología , Lucha/fisiología , Humanos
18.
Int J Sports Med ; 41(1): 54-58, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31747701

RESUMEN

This study aimed to investigate exposure adjusted injury incidence rates and profiles associated with training and competition in an elite taekwondo athlete population. 82 athletes were investigated for injuries over a period of 5 years. Individual fight time exposure for training and competition was recorded. The type and location of the injuries were classified and exposure-adjusted injury incidence rates (IIR) were calculated per 1000 h for training and competition. 66 athletes with a mean age of 19.3±4.2 years and 172 injuries were included in the final data assessment. The exposure adjusted IIR was significantly higher during competition (p<0.001) with a rate ratio of 6.33 (95% CI 4.58-8.69). Ankle and foot region as well as hand and wrist were most affected with significant higher IIR in competition (p<0.001). Joint injuries, fractures, and bruising occurred the most. Fractures occurred mainly to the hand and wrist region. Future investigations should focus on exposure adjusted injury data including analyses of the detailed mechanism leading to especially severe injuries to improve specific injury prevention in competition and promote evolution of protective gear.


Asunto(s)
Traumatismos en Atletas/epidemiología , Conducta Competitiva/fisiología , Artes Marciales/lesiones , Acondicionamiento Físico Humano/efectos adversos , Adolescente , Adulto , Traumatismos del Tobillo/epidemiología , Femenino , Traumatismos de los Pies/epidemiología , Traumatismos de la Mano/epidemiología , Humanos , Incidencia , Masculino , Estudios Prospectivos , Traumatismos de la Muñeca/epidemiología , Adulto Joven
19.
Sports Biomech ; 19(5): 665-677, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30274543

RESUMEN

Fractionated reaction time can be used to determine distinct epochs known as pre-motor, response and movement times (MTs) of a reaction time task. The purpose of this study was to compare elite and novice athletes performing a taekwondo kick in terms of the fractionated reaction time and electromyography (EMG) activation patterns of the muscles of the striking lower limb and the lower back. We hypothesised that the pre-motor time, response time (RT) and MT would be the shorter for elite athletes compared to novices. We collected data on 13 elite and 10 novice athletes when performing a roundhouse kick. The experiment included EMG electrodes placed on five low back and lower extremity muscles and an electrogoniometer placed on the kicking knee. We found that pre-motor time was shorter and the RT was longer for elite athletes than novice athletes. Moreover, the integrated EMG of the main knee extensor does not differ between groups though other leg and trunk muscles do. The results allow coaches and teachers to understand this particular taekwondo kicking movement which could ultimately improve the technique in order to establish training and teaching goals.


Asunto(s)
Conducta Competitiva/fisiología , Artes Marciales/fisiología , Músculo Esquelético/fisiología , Tiempo de Reacción , Estimulación Acústica , Adulto , Músculos de la Espalda/fisiología , Fenómenos Biomecánicos , Electromiografía , Femenino , Humanos , Extremidad Inferior/fisiología , Masculino , Adulto Joven
20.
Sports Biomech ; 19(3): 281-294, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29782218

RESUMEN

The aim was to evaluate the effects of judo combat on the athletes' postural control (PC) and physiological loading before, during and after a simulated match. Seventeen under-20 regional and national level athletes completed one modified 7-min match. At baseline, during the combat (3rd and 7th minutes) and 2-min post-match centre of pressure (CoP) parameters were assessed. Heart rate (HR), blood lactate (BLa) and rating of perceived exertion (RPE) and local RPE (LRPE) were collected. Significant increments were observed in CoP mean positioning and velocity at 3rd and 7th minutes, but the CoP deviation in both axes was unaffected. HR and BLa were elevated at 3rd and 7th minutes, and they remained elevated 2-min post-match. However, CoP returned to baseline 2-min post-match. RPE was elevated at 3rd and 7th minutes and the greatest effort was displayed in the Deltoid and Quadriceps. Thus, one simulated judo match stimulates a significant metabolic response and balance is degraded, with the greatest effects on the anterior-posterior axis and it recovers to baseline level after 2 min of passive rest. The physiological load cannot be regarded as a potential predictor variable of CoP. Overall, a judo match predominantly affects the upper body than the other body parts.


Asunto(s)
Conducta Competitiva/fisiología , Artes Marciales/fisiología , Equilibrio Postural/fisiología , Adolescente , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Fuerza Muscular/fisiología , Percepción/fisiología , Esfuerzo Físico/fisiología , Adulto Joven
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