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1.
J Pediatr Orthop ; 37(8): 511-520, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26683504

RESUMEN

BACKGROUND: Although supracondylar humerus fractures are common in young children, the incidence in adolescents is much lower. As a result, there is a paucity of literature to guide treatment. The purpose of this study was to review the treatment and outcomes for a consecutive series of distal humerus fractures in adolescents and to compare outcomes between patients treated with percutaneous skeletal fixation and those treated with open reduction and fixation. METHODS: A retrospective review of patients 10 to 17 years of age who underwent surgical treatment for a distal humerus fracture from 2005 to 2014 was performed. Patients with medial epicondyle fractures and those with insufficient follow-up to document union or return of motion were excluded. Medical records were reviewed to collect demographic data as well as operative approach and method of fixation. Clinical outcomes included range of motion, time to maximum motion, and complications [nerve dysfunction, heterotopic ossification (HO), need for secondary surgery]. Radiographs were reviewed to determine time to union as well as coronal and sagittal alignment. RESULTS: One hundred eighteen adolescents with displaced distal humerus fractures were identified. Eighty-one met inclusion criteria. Forty-four of these were classified as extra-articular [Orthopaedic Trauma Association (OTA) 13-A], and 37 were intra-articular fractures (10 OTA 13-B and 27 OTA 13-C).Although not statistically significant, closed treatment with percutaneous fixation of extra-articular fractures resulted in greater flexion-extension arc of motion at final follow-up (128 vs. 119 degrees, P=0.17) and demonstrated more rapid return of motion (2.8 vs. 3.9 mo, P=0.05) when compared with open treatment despite a longer duration of immobilization and less formal physical therapy. Complications such as HO (P=0.05), nerve dysfunction (P=0.02), and secondary surgery (P=0.001) were more common in the open treatment group.Closed treatment with percutaneous fixation of intra-articular fractures was performed in younger patients of similar size (12.8 vs. 14.4 y, P<0.01; 154 vs. 142 lbs, P=0.5). There were no significant differences between groups in regard to outcomes or complications. There were trends toward increased frequency of HO, nerve dysfunction, and secondary surgery in the open treatment group.Patients with intra-articular fractures were older (14.2 vs. 11.5 y, P<0.001) and heavier (144 vs. 94 lbs, P<0.001) than patients with extra-articular fractures and were more likely to be treated open (74% vs. 11%, P<0.001). Extra-articular fractures demonstrated a greater total arc of motion (126 vs. 118 degrees, P=0.04) at final follow-up despite longer duration of immobilization (23 vs. 15 d, P=0.002), and less physical therapy (27% vs. 73%, P<0.001). Radiographic carrying angle (16.6 vs. 22.3 degrees, P=0.08) and anterior humeral line (95% vs. 81%, P=0.07) trended toward more anatomic alignment in the extra-articular group. Secondary surgery was more common after intra-articular fracture (24% vs. 7%, P=0.03). CONCLUSIONS: Closed reduction and pinning of extra-articular distal humerus fractures in adolescents resulted in predictable clinical and radiographic outcomes and allowed for earlier return of motion and fewer complications when compared with open treatment. Intra-articular distal humerus fractures occur more frequently in older adolescents and are more likely to require open reduction and internal fixation to obtain joint congruity. Patients with intra-articular injuries should be cautioned that regaining full elbow motion may be more difficult, and there is an increased risk for complications and need for additional surgery. Closed reduction and percutaneous fixation of intra-articular injuries appears to be a reasonable option in select patients. LEVEL OF EVIDENCE: Level III-retrospective comparative study.


Asunto(s)
Articulación del Codo/cirugía , Fijación Intramedular de Fracturas/métodos , Fracturas del Húmero/cirugía , Reducción Abierta/métodos , Adolescente , Niño , Articulación del Codo/diagnóstico por imagen , Femenino , Humanos , Fracturas del Húmero/diagnóstico por imagen , Fracturas Intraarticulares/diagnóstico por imagen , Fracturas Intraarticulares/cirugía , Masculino , Radiografía , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento
2.
Eur J Nutr ; 55(4): 1695-705, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26163338

RESUMEN

PURPOSE: To investigate the phytochemical uptake following human consumption of Montmorency tart cherry (L. Prunus cerasus) and influence of selected phenolic acids on vascular smooth muscle cells in vitro. METHODS: In a randomised, double-blinded, crossover design, 12 healthy males consumed either 30 or 60 mL of Montmorency tart cherry concentrate. Following analysis of the juice composition, venous blood samples were taken before and 1, 2, 3, 5 and 8 h post-consumption of the beverage. In addition to examining some aspects of the concentrate contents, plasma concentrations of protocatechuic acid (PCA), vanillic acid (VA) and chlorogenic (CHL) acid were analysed by reversed-phase high-performance liquid chromatography (HPLC) with diode array for quantitation and mass spectrometry detection (LCMS) for qualitative purposes. Vascular smooth muscle cell migration and proliferation were also assessed in vitro. RESULTS: Both the 30 and 60 mL doses of Montmorency cherry concentrate contained high amounts of total phenolics (71.37 ± 0.11; 142.73 ± 0.22 mg/L) and total anthocyanins (62.47 ± 0.31; 31.24 ± 0.16 mg/L), as well as large quantities of CHL (0.205 ± 0.24; 0.410 ± 0.48 mg/L) and VA (0.253 ± 0.84; 0.506 ± 1.68 mg/L). HPLC/LCMS identified two dihydroxybenzoic acids (PCA and VA) in plasma following MC concentrate consumption. Both compounds were most abundant 1-2 h post-initial ingestion with traces detectable at 8 h post-ingestion. Cell migration was significantly influenced by the combination of PCA and VA, but not in isolation. There was no effect of the compounds on cell proliferation. CONCLUSIONS: These data show new information that phenolic compounds thought to exert vasoactive properties are bioavailable in vivo following MC consumption and subsequently can influence cell behaviour. These data may be useful for the design and interpretation of intervention studies investigating the health effects of Montmorency cherries.


Asunto(s)
Hidroxibenzoatos/farmacología , Miocitos del Músculo Liso/efectos de los fármacos , Fitoquímicos/farmacología , Prunus avium/química , Adulto , Antocianinas/sangre , Antocianinas/farmacología , Antioxidantes/análisis , Antioxidantes/farmacología , Bebidas/análisis , Índice de Masa Corporal , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Ácido Clorogénico/sangre , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Estudios de Evaluación como Asunto , Frutas/química , Humanos , Hidroxibenzoatos/sangre , Masculino , Músculo Liso Vascular/citología , Estrés Oxidativo/efectos de los fármacos , Fenoles/sangre , Fenoles/farmacología , Fitoquímicos/sangre , Ácido Vanílico/sangre , Adulto Joven
3.
J Sports Sci ; 33(15): 1544-52, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25573221

RESUMEN

This study investigated the effects of two different hydrostatic pressures (seated or standing) during cold water immersion at attenuating the deleterious effects of strenuous exercise on indices of damage and recovery. Twenty four male well-trained games players (age 23 ± 3 years; body mass 81.4 ± 8.7 kg: [Formula: see text]O2max 57.5 ± 4.9 ml∙kg(-1)∙min(-1)) completed the Loughborough Intermittent Shuttle Test (LIST) and were randomly assigned to either a control, seated cold water immersion or a standing cold water immersion (14 min at 14°C). Maximal isometric voluntary contraction, counter-movement jump, creatine kinase, C-reactive protein, interleukin-6 and delayed onset muscle soreness (DOMS) were measured before and up to 72 h following the LIST. All dependent variables showed main effects for time (P < 0.05) following the LIST, indicating physiological stress and muscle damage following the exercise. There were no significant group differences between control and either of the cold water immersion interventions. Seated cold water immersion was associated with lower DOMS than standing cold water immersion (effect size = 1.86; P = 0.001). These data suggest that increasing hydrostatic pressure by standing in cold water does not provide an additional recovery benefit over seated cold water immersion, and that both seated and standing immersions have no benefit in promoting recovery following intermittent sprint exercise.


Asunto(s)
Crioterapia , Inmersión , Postura/fisiología , Recuperación de la Función/fisiología , Carrera/fisiología , Traumatismos en Atletas/prevención & control , Proteína C-Reactiva/análisis , Creatina Quinasa/sangre , Humanos , Interleucina-6/sangre , Contracción Isométrica/fisiología , Masculino , Mialgia/fisiopatología , Mialgia/prevención & control , Distribución Aleatoria , Adulto Joven
4.
Eur J Sport Sci ; 23(7): 1334-1344, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35771645

RESUMEN

Athletes often undertake intensified training loads prior to competition with the goal of functionally overreaching for temporary performance enhancement; however, little is known about the impact of this on cognitive function. The aim of this study was to investigate the effect of intensified training induced fatigue on cognitive function, psychological state and performance in trained cyclists. Twenty-three trained male cyclists were randomly assigned to an intensified training group or a control group for two-weeks, followed by a two-week taper period. At baseline, one-week, two-weeks and post-taper, participants undertook a series of cognitive, performance, mood and recovery-stress assessments. The training intervention significantly increased training volume, load and strain by 108%, 116% and 151% respectively. Peak and mean power output on a maximal test and time trial significantly decreased by 4.8% and 9.4% following the two-week training intervention compared to baseline, in addition to a 169% change in total mood disturbance and significant disruption to recovery-stress balance. No change in any cognitive measure was observed across the study period. Following a two-week taper, performance, mood and well-being measures returned to baseline. Two weeks of intensified training resulted in overreaching as identified by performance and psychological measures. Cognitive function was not sensitive to intensified training promoting caution with its use as a measure for the early identification of overreaching.HighlightsTwo-weeks of intensified training significantly increased training volume, load and strain eliciting a state of overreaching in trained male cyclists.Intensified training caused deteriorations in physical performance but did not influence cognitive measures.Mood and recovery-stress balance were negatively affected by intensified training but recovered back to baseline following a two-week taper at a reduced training volume.A two-week taper period following two-weeks of intensified training did not result in improved physiological measures, physical performance parameters or mood above initial baseline values highlighting the need for careful consideration over the purpose, desired outcomes and necessity of intensified training on an individualised basis.


Asunto(s)
Ciclismo , Fatiga , Humanos , Masculino , Ciclismo/fisiología , Cognición , Resistencia Física/fisiología
5.
Front Physiol ; 14: 1213733, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37476688

RESUMEN

Purpose: Hot water immersion (HWI) is a strategy theorised to enhance exercise recovery. However, the acute physiological responses to HWI following resistance exercise are yet to be determined. Methods: The effect of HWI on intramuscular temperature (IMT), muscle function, muscle soreness and blood markers of muscle cell disruption and inflammatory processes after resistance exercise was assessed. Sixteen resistance trained males performed resistance exercise, followed by either 10 min HWI at 40°C or 10 min passive recovery (PAS). Results: Post-intervention, the increase in IMT at all depths was greater for HWI compared to PAS, however this difference had disappeared by 1 h post at depths of 1 and 2 cm, and by 2 h post at a depth of 3 cm. There were no differences between groups for muscle function, muscle soreness or any blood markers. Conclusion: These results suggest that HWI is a viable means of heat therapy to support a greater IMT following resistance exercise. Recovery of muscle function and muscle soreness is independent of acute changes in IMT associated with HWI.

6.
Eur J Nutr ; 51(8): 909-16, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22038497

RESUMEN

BACKGROUND: Tart Montmorency cherries have been reported to contain high levels of phytochemicals including melatonin, a molecule critical in regulating the sleep-wake cycle in humans. PURPOSE: The aim of our investigation was to ascertain whether ingestion of a tart cherry juice concentrate would increase the urinary melatonin levels in healthy adults and improve sleep quality. METHODS: In a randomised, double-blind, placebo-controlled, crossover design, 20 volunteers consumed either a placebo or tart cherry juice concentrate for 7 days. Measures of sleep quality recorded by actigraphy and subjective sleep questionnaires were completed. Sequential urine samples over 48 h were collected and urinary 6-sulfatoxymelatonin (major metabolite of melatonin) determined; cosinor analysis was used to determine melatonin circadian rhythm (mesor, acrophase and amplitude). In addition, total urinary melatonin content was determined over the sampled period. Trial differences were determined using a repeated measures ANOVA. RESULTS: Total melatonin content was significantly elevated (P < 0.05) in the cherry juice group, whilst no differences were shown between baseline and placebo trials. There were significant increases in time in bed, total sleep time and sleep efficiency total (P < 0.05) with cherry juice supplementation. Although there was no difference in timing of the melatonin circardian rhythm, there was a trend to a higher mesor and amplitude. CONCLUSIONS: These data suggest that consumption of a tart cherry juice concentrate provides an increase in exogenous melatonin that is beneficial in improving sleep duration and quality in healthy men and women and might be of benefit in managing disturbed sleep.


Asunto(s)
Bebidas/análisis , Suplementos Dietéticos , Melatonina/análogos & derivados , Prunus/química , Trastornos del Sueño-Vigilia/terapia , Sueño/efectos de los fármacos , Actigrafía/métodos , Adolescente , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Frutas/química , Humanos , Masculino , Melatonina/orina , Trastornos del Sueño-Vigilia/fisiopatología , Encuestas y Cuestionarios , Adulto Joven
7.
Curr Opin Nephrol Hypertens ; 18(1): 57-62, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19077690

RESUMEN

PURPOSE OF REVIEW: To summarize recent evidence regarding the role of distal nephron segments other than the macula densa in sensing the tubular environment and transmitting this signal to the adjacent vasculature. RECENT FINDINGS: In addition to the classical contact site between the macula densa plaque and the afferent arteriole, there is accumulating evidence suggesting a functional association between the distal nephron and the vasculature at three distinct additional sites: at the terminal cortical thick ascending limb, at the early distal tubule and also at the connecting tubule segment. The epithelial cells around the macula densa also sense and respond to changes in tubular flow and salt content and may transmit this signal to the adjacent afferent arteriole. SUMMARY: There are multiple sites of anatomical and functional contact between the distal nephron and the vasculature supplying the glomerulus, and these may contribute to the regulation of glomerular filtration rate and renal hemodynamics.


Asunto(s)
Glomérulos Renales/fisiología , Túbulos Renales Distales/fisiología , Nefronas/fisiología , Animales , Retroalimentación/fisiología , Humanos , Glomérulos Renales/anatomía & histología , Transducción de Señal/fisiología
8.
Appl Physiol Nutr Metab ; 44(3): 309-319, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30189146

RESUMEN

A variety of strategies exist to modulate the acute physiological responses following resistance exercise aimed at enhancing recovery and/or adaptation processes. To assess the true impact of these strategies, it is important to know the ability of different measures to detect meaningful change. We investigated the sensitivity of measures used to quantify acute physiological responses to resistance exercise and constructed a physiological profile to characterise the magnitude of change and the time course of these responses. Eight males accustomed to regular resistance exercise performed experimental sessions during a "control week", void of an exercise stimulus. The following week, termed the "exercise week", participants repeated this sequence of experimental sessions, and they also performed a bout of lower-limb resistance exercise following the baseline assessments. Assessments were conducted at baseline and at 2, 6, 24, 48, 72, and 96 h after the intervention. On the basis of the signal-to-noise ratio, the most sensitive measures were maximal voluntary isometric contraction, 20-m sprint, countermovement jump peak force, rate of force development (100-200 ms), muscle soreness, Daily Analysis Of Life Demands For Athletes part B, limb girth, matrix metalloproteinase-9, interleukin-6, creatine kinase, and high-sensitivity C-reactive protein with ratios >1.5. Clear changes in these measures following resistance exercise were determined via magnitude-based inferences. These findings highlight measures that can detect real changes in acute physiological responses following resistance exercise in trained individuals. Researchers investigating strategies to manipulate acute physiological responses for recovery and/or adaptation can use these measures, as well as the recommended sampling points, to be confident that their interventions are making a worthwhile impact.


Asunto(s)
Adaptación Fisiológica , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Adolescente , Proteína C-Reactiva/análisis , Creatina Quinasa/sangre , Humanos , Interleucina-6/sangre , Contracción Isométrica , Extremidad Inferior , Masculino , Metaloproteinasa 9 de la Matriz/sangre , Mialgia , Adulto Joven
9.
Appl Physiol Nutr Metab ; 43(2): 113-122, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28972854

RESUMEN

The consumption of milk following eccentric exercise attenuates the effects of muscle damage in team-sport athletes. However, participation in team sport involves both concentric-eccentric loading and metabolic stress. Therefore, the aim of this study was to investigate the effects of postexercise milk consumption on recovery from a cycling protocol designed to simulate the metabolic demands of team sport. Ten female team-sport athletes participated in a randomised crossover investigation. Upon completion of the protocol participants consumed 500 mL of milk (MILK) or 500 mL of an energy-matched carbohydrate (CHO) drink. Muscle function (peak torque, rate of force development, countermovement jump, 20-m sprint), muscle soreness and tiredness, serum creatine kinase, high-sensitivity C-reactive protein, and measures of oxidative stress (protein carbonyls and reduced glutathione/oxidized glutathione (GSH/GSSG) ratio) were determined at pre-exercise and 24 h, 48 h, and 72 h postexercise. MILK had a possible beneficial effect in attenuating losses in peak torque (180°/s) from baseline to 24 h (3.2% ± 7.8% vs. -6.2% ± 7.5%, MILK vs. CHO) and a possible beneficial effect in minimising soreness (baseline-48 h; baseline-72 h) and tiredness (baseline-24 h; baseline-72 h). There was no change in oxidative stress following the exercise protocol, though a likely benefit of milk was observed for GSH/GSSG ratio at baseline-24 h (0.369 ×/÷ 1.89, 1.103 ×/÷ 3.96, MILK vs. CHO). MILK had an unclear effect on all other variables. Consumption of 500 mL of milk after repeat sprint cycling had little to no benefit in minimising losses in peak torque or minimising increases in soreness and tiredness and had no effect on serum markers of muscle damage and inflammation.


Asunto(s)
Rendimiento Atlético , Ciclismo , Leche , Músculo Esquelético/fisiología , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto , Animales , Atletas , Proteína C-Reactiva/metabolismo , Creatina Quinasa/sangre , Estudios Cruzados , Dieta , Ácido Edético/sangre , Ejercicio Físico , Femenino , Heparina/sangre , Humanos , Inflamación/sangre , Mialgia/prevención & control , Estrés Oxidativo , Estrés Fisiológico , Encuestas y Cuestionarios , Adulto Joven
10.
Sci Rep ; 8(1): 1898, 2018 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-29382913

RESUMEN

It is unknown if adult human skeletal muscle has an epigenetic memory of earlier encounters with growth. We report, for the first time in humans, genome-wide DNA methylation (850,000 CpGs) and gene expression analysis after muscle hypertrophy (loading), return of muscle mass to baseline (unloading), followed by later hypertrophy (reloading). We discovered increased frequency of hypomethylation across the genome after reloading (18,816 CpGs) versus earlier loading (9,153 CpG sites). We also identified AXIN1, GRIK2, CAMK4, TRAF1 as hypomethylated genes with enhanced expression after loading that maintained their hypomethylated status even during unloading where muscle mass returned to control levels, indicating a memory of these genes methylation signatures following earlier hypertrophy. Further, UBR5, RPL35a, HEG1, PLA2G16, SETD3 displayed hypomethylation and enhanced gene expression following loading, and demonstrated the largest increases in hypomethylation, gene expression and muscle mass after later reloading, indicating an epigenetic memory in these genes. Finally, genes; GRIK2, TRAF1, BICC1, STAG1 were epigenetically sensitive to acute exercise demonstrating hypomethylation after a single bout of resistance exercise that was maintained 22 weeks later with the largest increase in gene expression and muscle mass after reloading. Overall, we identify an important epigenetic role for a number of largely unstudied genes in muscle hypertrophy/memory.


Asunto(s)
Epigénesis Genética/genética , Hipertrofia/genética , Músculo Esquelético/fisiología , Adulto , Metilación de ADN/genética , Epigenómica/métodos , Expresión Génica/genética , Humanos , Masculino
11.
Med Sci Sports Exerc ; 49(1): 115-123, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27508883

RESUMEN

INTRODUCTION: This case study reports a range of physiological characteristics in a two-time Tour de France champion. METHODS: After body composition assessment (dual-energy x-ray absorptiometry), two submaximal cycling step tests were performed in ambient (20°C, 40%) and hot and humid (30°C, 60% [HH]) conditions from which measures of gross efficiency (GE), lactate-power landmarks, and heart rate responses were calculated. In addition, thermoregulatory and sweat responses were collected throughout. V˙O2peak and peak power output (PPO) were also identified after a separate ramp test to exhaustion. RESULTS: V˙O2peak and PPO were 5.91 L·min (84 mL·kg·min) and 525 W, respectively, whereas mean GE values were 23.0% and 23.6% for ambient and HH conditions, respectively. In addition to superior GE, power output at 4 mmol·L lactate was higher in HH versus ambient conditions (429.6 vs 419.0 W) supporting anecdotal reports from the participant of good performance in the heat. Peak core and skin temperature, sweat rate, and electrolyte content were higher in HH conditions. Body fat percentage was 9.5%, whereas total fat mass, lean mass, and bone mineral content were 6.7, 61.5, and 2.8 kg, respectively. CONCLUSION: The aerobic physiology and PPO values indentified are among the highest reported for professional road cyclists. Notably, the participant displayed both a high V˙O2peak and GE, which is uncommon among elite cyclists and may be a contributing factor to their success in elite cycling. In addition, performance in HH conditions was strong, suggesting effective thermoregulatory physiology. In summary, this is the first study to report physiological characteristics of a multiple Tour de France champion in close to peak condition and suggests what may be the prerequisite physiological and thermoregulatory capacities for success at this level.


Asunto(s)
Ciclismo/fisiología , Conducta Competitiva/fisiología , Resistencia Física/fisiología , Adulto , Composición Corporal , Densidad Ósea , Francia , Frecuencia Cardíaca/fisiología , Calor , Humanos , Humedad , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno/fisiología , Aptitud Física/fisiología , Sudoración/fisiología
12.
Prog Brain Res ; 234: 161-187, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29031462

RESUMEN

BACKGROUND: High-intensity exercise is generally considered to have detrimental effects on cognition. However, high fitness levels are suggested to alleviate this effect. OBJECTIVES: The specific objective of this review was to evaluate the literature on the effect of acute high-intensity exercise on cognitive performance in trained individuals. METHODS: Studies were sourced through electronic databases, reference lists of retrieved articles, and manual searches of relevant reviews. Included studies examined trained participants, included a high-intensity exercise bout, used a control or comparison group/condition, and assessed cognitive performance via general laboratory tasks during or ≤10min following exercise cessation. RESULTS: Ten articles met the inclusion criteria. Results indicated that the effect of acute high-intensity exercise on cognitive performance in trained individuals is dependent on the specific cognitive domain being assessed. Generally, simple tasks were not affected, while the results on complex tasks remain ambiguous. Accuracy showed little tendency to be influenced by high-intensity exercise compared to measures of speed. CONCLUSION: Multiple factors influence the acute exercise-cognition relationship and thus future research should be highly specific when outlining criteria such as fitness levels, exercise intensity, and exercise mode. Furthermore, greater research is needed assessing more cognitive domains, greater exercise durations/types, and trained populations at high intensities.


Asunto(s)
Cognición/fisiología , Ejercicio Físico/psicología , Deportes , Enseñanza/psicología , Humanos , Deportes/fisiología , Deportes/psicología
13.
Nutrients ; 8(7)2016 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-27455316

RESUMEN

This study investigated Montmorency tart cherry concentrate (MC) supplementation on markers of recovery following prolonged, intermittent sprint activity. Sixteen semi-professional, male soccer players, who had dietary restrictions imposed for the duration of the study, were divided into two equal groups and consumed either MC or placebo (PLA) supplementation for eight consecutive days (30 mL twice per day). On day 5, participants completed an adapted version of the Loughborough Intermittent Shuttle Test (LISTADAPT). Maximal voluntary isometric contraction (MVIC), 20 m Sprint, counter movement jump (CMJ), agility and muscle soreness (DOMS) were assessed at baseline, and 24, 48 and 72 h post-exercise. Measures of inflammation (IL-1-ß, IL-6, IL-8, TNF-α, hsCRP), muscle damage (CK) and oxidative stress (LOOH) were analysed at baseline and 1, 3, 5, 24, 48 and 72 h post-exercise. Performance indices (MVIC, CMJ and agility) recovered faster and muscle soreness (DOMS) ratings were lower in the MC group (p < 0.05). Additionally, the acute inflammatory response (IL-6) was attenuated in the MC group. There were no effects for LOOH and CK. These findings suggest MC is efficacious in accelerating recovery following prolonged, repeat sprint activity, such as soccer and rugby, and lends further evidence that polyphenol-rich foods like MC are effective in accelerating recovery following various types of strenuous exercise.


Asunto(s)
Jugos de Frutas y Vegetales , Alimentos Funcionales , Entrenamiento de Intervalos de Alta Intensidad/efectos adversos , Músculo Esquelético/metabolismo , Miositis/prevención & control , Prunus/química , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto , Atletas , Rendimiento Atlético , Biomarcadores/sangre , Método Doble Ciego , Manipulación de Alimentos , Humanos , Mediadores de Inflamación/sangre , Mediadores de Inflamación/metabolismo , Masculino , Músculo Esquelético/inmunología , Músculo Esquelético/fisiopatología , Mialgia/etiología , Mialgia/prevención & control , Miositis/sangre , Miositis/inmunología , Miositis/fisiopatología , Estrés Oxidativo , Carrera , Fútbol , Reino Unido , Adulto Joven
14.
Curr Neurovasc Res ; 2(1): 3-12, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16181095

RESUMEN

The Na+/Ca2+ exchangers, RNCX and SNCX, were cloned from mesangial cells of salt sensitive and salt resistant Dahl/Rapp rats, respectively, and differ at amino acid 218 (RNCXi/SNCXf) and in the exons expressed at the alternative splice site (RNCXB, D/SNCXB, D, F). These isoforms are also expressed in myocytes, neurons, and astrocytes where they maintain cytosolic calcium homeostasis. We demonstrated that cells expressing SNCX were more susceptible to oxidative stress than cells expressing RNCX. Others demonstrated that amyloid beta peptide (Abeta) augments the adverse effects of oxidative stress on calcium homeostasis. Therefore, we sought to assess the effect of Abeta 1-40 on the abilities of OK-PTH cells stably expressing RNCX and SNCX and human glioma cells, SKMG1, to regulate cytosolic calcium homeostasis. Our studies showed that Abeta 1-40 (1 microM) did not affect RNCX activity, as assessed by changes in [Ca2+]i (Delta[Ca2+]i, 260+/-10 nM to 267+/-8 nM), while stimulating exchange activity 2.4 and 3 fold in cells expressing SNCX (100+/-8 to 244+/-12 nM) and in SKMG1 cells (90+/-11 nM to 270+/-18 nM), respectively. Our results also showed that Abeta 1-40, while not affecting the rate of Mn2+ influx in cells expressing RNCX, stimulated the rate of Mn2+ influx 2.8 and 2.9 fold in cells expressing SNCX and in SKMG1 cells. Thus, our studies demonstrate that Abeta-induced cytosolic calcium increase is mediated through certain isoforms of the Na+/Ca2+ exchanger and reveals a possible mechanism by which Abeta 1-40 can alter cytosolic calcium homeostasis.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Fragmentos de Péptidos/farmacología , Intercambiador de Sodio-Calcio/metabolismo , Animales , Calcio/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Homeostasis/efectos de los fármacos , Humanos , Membranas Intracelulares/metabolismo , Manganeso/metabolismo , Zarigüeyas , Concentración Osmolar , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Endogámicas Dahl
15.
Appl Physiol Nutr Metab ; 40(4): 414-23, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25794236

RESUMEN

The impact of Montmorency tart cherry (Prunus cerasus L.) concentrate (MC) on physiological indices and functional performance was examined following a bout of high-intensity stochastic cycling. Trained cyclists (n = 16) were equally divided into 2 groups (MC or isoenergetic placebo (PLA)) and consumed 30 mL of supplement, twice per day for 8 consecutive days. On the fifth day of supplementation, participants completed a 109-min cycling trial designed to replicate road race demands. Functional performance (maximum voluntary isometric contraction (MVIC), cycling efficiency, 6-s peak cycling power) and delayed onset muscle soreness were assessed at baseline, 24, 48, and 72 h post-trial. Blood samples collected at baseline, immediately pre- and post-trial, and at 1, 3, 5, 24, 48, and 72 h post-trial were analysed for indices of inflammation (interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor alpha, high-sensitivity C-reactive protein (hsCRP)), oxidative stress (lipid hydroperoxides), and muscle damage (creatine kinase). MVIC (P < 0.05) did not decline in the MC group (vs. PLA) across the 72-h post-trial period and economy (P < 0.05) was improved in the MC group at 24 h. IL-6 (P < 0.001) and hsCRP (P < 0.05) responses to the trial were attenuated with MC (vs. PLA). No other blood markers were significantly different between MC and PLA groups. The results of the study suggest that Montmorency cherry concentrate can be an efficacious functional food for accelerating recovery and reducing exercise-induced inflammation following strenuous cycling exercise.


Asunto(s)
Ejercicio Físico , Frutas , Alimentos Funcionales , Prunus avium , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto , Ciclismo , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Creatina Quinasa/sangre , Dieta , Método Doble Ciego , Humanos , Inflamación/sangre , Inflamación/terapia , Interleucina-1beta/sangre , Interleucina-6/sangre , Interleucina-8/sangre , Contracción Isométrica/fisiología , Masculino , Músculo Esquelético/metabolismo , Estrés Oxidativo/fisiología , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven
16.
Nutrients ; 6(2): 829-43, 2014 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-24566440

RESUMEN

This investigation examined the impact of Montmorency tart cherry concentrate (MC) on physiological indices of oxidative stress, inflammation and muscle damage across 3 days simulated road cycle racing. Trained cyclists (n = 16) were divided into equal groups and consumed 30 mL of MC or placebo (PLA), twice per day for seven consecutive days. A simulated, high-intensity, stochastic road cycling trial, lasting 109 min, was completed on days 5, 6 and 7. Oxidative stress and inflammation were measured from blood samples collected at baseline and immediately pre- and post-trial on days 5, 6 and 7. Analyses for lipid hydroperoxides (LOOH), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-8 (IL-8), interleukin-1-beta (IL-1-ß), high-sensitivity C-reactive protein (hsCRP) and creatine kinase (CK) were conducted. LOOH (p < 0.01), IL-6 (p < 0.05) and hsCRP (p < 0.05) responses to trials were lower in the MC group versus PLA. No group or interaction effects were found for the other markers. The attenuated oxidative and inflammatory responses suggest MC may be efficacious in combating post-exercise oxidative and inflammatory cascades that can contribute to cellular disruption. Additionally, we demonstrate direct application for MC in repeated days cycling and conceivably other sporting scenario's where back-to-back performances are required.


Asunto(s)
Antioxidantes/farmacología , Ciclismo/fisiología , Frutas , Estrés Oxidativo , Prunus/química , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto , Bebidas , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Suplementos Dietéticos , Método Doble Ciego , Humanos , Inflamación/sangre , Interleucina-1beta/sangre , Interleucina-6/sangre , Interleucina-8/sangre , Masculino , Músculo Esquelético/metabolismo , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven
17.
Med Sci Sports Exerc ; 45(8): 1585-92, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23470297

RESUMEN

INTRODUCTION: Exercise-induced muscle damage (EIMD) leads to increases in intramuscular proteins observed in the blood stream and delayed onset of muscle soreness, but crucial for athletes are the decrements in muscle performance observed. Previous research has demonstrated that carbohydrate-protein supplements limit these decrements; however, they have primarily used isokinetic dynamometry, which has limited applicability to dynamic sport settings. Therefore, the aim of this study was to investigate the effects of a carbohydrate-protein milk supplement consumed after muscle-damaging exercise on performance tests specific to field-based team sports. METHODS: Two independent groups of seven males consumed either 500 mL of milk or a control immediately after muscle-damaging exercise. Passive and active delayed onset of muscle soreness, creatine kinase, myoglobin, countermovement jump height, reactive strength index, 15-m sprint, and agility time were assessed before and 24, 48, and 72 h after EIMD. The Loughborough Intermittent Shuttle Test was also performed before and 48 h after EIMD. RESULTS: At 48 h, milk had a possible benefit for limiting increases in 10-m sprint time and a likely benefit of attenuating increases in mean 15-m sprint time during the Loughborough Intermittent Shuttle Test. At 72 h, milk had a possible benefit for limiting increases in 15-m sprint time and a likely benefit for the attenuation of increases in agility time. All other effects for measured variables were unclear. CONCLUSION: The consumption of milk limits decrements in one-off sprinting and agility performance and the ability to perform repeated sprints during the physiological simulation of field-based team sports.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Rendimiento Atlético/fisiología , Ejercicio Físico , Leche/efectos de los fármacos , Músculo Esquelético/lesiones , Mialgia/fisiopatología , Adulto , Animales , Traumatismos en Atletas/sangre , Traumatismos en Atletas/etiología , Creatina Quinasa/sangre , Prueba de Esfuerzo , Humanos , Masculino , Mialgia/sangre , Mialgia/etiología , Mioglobina/sangre , Adulto Joven
18.
Artículo en Inglés | MEDLINE | ID: mdl-22569039

RESUMEN

BACKGROUND: It is well documented that exercise-induced muscle damage (EIMD) decreases muscle function and causes soreness and discomfort. Branched-chain amino acid (BCAA) supplementation has been shown to increase protein synthesis and decrease muscle protein breakdown, however, the effects of BCAAs on recovery from damaging resistance training are unclear. Therefore, the aim of this study was to examine the effects of a BCAA supplementation on markers of muscle damage elicited via a sport specific bout of damaging exercise in trained volunteers. METHODS: Twelve males (mean ± SD age, 23 ± 2 y; stature, 178.3 ± 3.6 cm and body mass, 79.6 ± 8.4 kg) were randomly assigned to a supplement (n = 6) or placebo (n = 6) group. The damaging exercise consisted of 100 consecutive drop-jumps. Creatine kinase (CK), maximal voluntary contraction (MVC), muscle soreness (DOMS), vertical jump (VJ), thigh circumference (TC) and calf circumference (CC) were measured as markers of muscle damage. All variables were measured immediately before the damaging exercise and at 24, 48, 72 and 96 h post-exercise. RESULTS: A significant time effect was seen for all variables. There were significant group effects showing a reduction in CK efflux and muscle soreness in the BCAA group compared to the placebo (P<0.05). Furthermore, the recovery of MVC was greater in the BCAA group (P<0.05). The VJ, TC and CC were not different between groups. CONCLUSION: The present study has shown that BCAA administered before and following damaging resistance exercise reduces indices of muscle damage and accelerates recovery in resistance-trained males. It seems likely that BCAA provided greater bioavailablity of substrate to improve protein synthesis and thereby the extent of secondary muscle damage associated with strenuous resistance exercise. CLINICAL TRIAL REGISTRATION NUMBER: NCT01529281.

20.
J Med Case Rep ; 2: 306, 2008 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-18803821

RESUMEN

INTRODUCTION: Whilst rare, stress fractures of the clavicle have been described in other sports. To our knowledge, this is the first reported case of a stress fracture of the clavicle occurring in a cricket fast bowler. CASE PRESENTATION: A 23-year-old professional cricket fast bowler presented with activity related shoulder pain. Imaging demonstrated a stress fracture of the lateral third of the clavicle. This healed with rest and rehabilitation allowing a full return to professional sport. CONCLUSION: This injury is treated with activity modification and technique adaptation. In a professional sportsman, this needs to be recognised early so that return to play can be as quick as possible.

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