Injuries of the obturator muscles in professional soccer players.

PURPOSE: Obturator externus and internus muscular tears are uncommon injuries. Only a few case reports exist, mainly in high-level athletes. Our aim is to describe a series of obturator externus and internus muscular tears in professional soccer players. METHODS: Injury data from four teams from the First Division of the Spanish Soccer League were collected over a total of four seasons. Any soccer player who sustained an injury to either the obturator externus or internus identified on magnetic resonance (MRI) was included. All injured players were treated non-operatively with a goal of returning to play as fast as possible. RESULTS: Sixteen players sustained injuries to the obturator externus and internus during matches or training sessions. The main complaint was anterior hip pain with a physical examination showing pain during internal rotation or external rotation of the flexed hip. The MRI documented 12 muscular tears of the obturator externus, and 4 muscular tears of the obturator internus. All injuries were treated conservatively based on physical therapy, analgesic medications, and underwent a symptoms-based rehabilitation protocol. Mean return to play was 11.5  ±  8.8 days. CONCLUSION: Although uncommon, tears of the obturator externus and internus occur in professional soccer players. The MRI scan was essential to the location, classification, and evaluation of the injury size. The clinical relevance of our investigation is based on the relatively benign prognosis of these injuries. LEVEL OF EVIDENCE: IV.

Work-related pain in extrinsic finger extensor musculature of instrumentalists is associated with intracellular pH compartmentation during exercise.

BACKGROUND: Although non-specific pain in the upper limb muscles of workers engaged in mild repetitive tasks is a common occupational health problem, much is unknown about the associated structural and biochemical changes. In this study, we compared the muscle energy metabolism of the extrinsic finger extensor musculature in instrumentalists suffering from work-related pain with that of healthy control instrumentalists using non-invasive phosphorus magnetic resonance spectroscopy ((31)P-MRS). We hypothesize that the affected muscles will show alterations related with an impaired energy metabolism. METHODOLOGY/PRINCIPAL FINDINGS: We studied 19 volunteer instrumentalists (11 subjects with work-related pain affecting the extrinsic finger extensor musculature and 8 healthy controls). We used (31)P-MRS to find deviations from the expected metabolic response to exercise in phosphocreatine (PCr), inorganic phosphate (Pi), Pi/PCr ratio and intracellular pH kinetics. We observed a reduced finger extensor exercise tolerance in instrumentalists with myalgia, an intracellular pH compartmentation in the form of neutral and acid compartments, as detected by Pi peak splitting in (31)P-MRS spectra, predominantly in myalgic muscles, and a strong association of this pattern with the condition. CONCLUSIONS/SIGNIFICANCE: Work-related pain in the finger extrinsic extensor muscles is associated with intracellular pH compartmentation during exercise, non-invasively detectable by (31)P-MRS and consistent with the simultaneous energy production by oxidative metabolism and glycolysis. We speculate that a deficit in energy production by oxidative pathways may exist in the affected muscles. Two possible explanations for this would be the partial and/or local reduction of blood supply and the reduction of the muscle oxidative capacity itself.

Body image and body composition: comparisons of young male elite soccer players and controls.

The purpose of this study was to evaluate body composition and body image (perception and satisfaction) in a group of young elite soccer players and to compare the data with those of a control group (age and BMI matched). Participants were 56 volunteer males whose mean age and BMI were 19.6 (SD 1.3) years and 23.3 (SD 1.1) kg/m2, respectively. Results showed that soccer players have a higher lean mass and lower fat mass than controls. Moreover, body perception (difference between current and actual image) was more accurate in controls than in soccer players, and the results suggest a tendency for soccer players to aspire to have more muscle mass and body fat. Soccer players perceived an ideal image with significantly higher body-fat percentage than their current and actual images. There were no body-dissatisfaction differences between groups, however. Although the results are necessarily limited by the small sample size, the findings should be of interest to coaches of young elite soccer teams.

Physiological adaptation during short distance triathlon swimming and cycling sectors simulation.

The aim of this study was to typify cardiorespiratory and metabolic adaptation capacity at race pace of high-level triathletes during simulations of short distance triathlon swimming sector, first transition and cycling sector. Six national and international-level triathletes performed a 1500 m swimming trial followed by a transition and one hour on ergocycle at race pace, with sequenced measures of blood lactate concentration, gas exchange and heart rate recording. The mean speed obtained in the swimming sector was 1.29+/-0.07 m s(-1), matching 98+/-2% of MAS (Maximal Aerobic Speed), lactate concentration 6.8+/-2.1 mM and heart rate 162+/-15 beats min(-1). In the cycling sector, the mean power was 266+/-34 W, matching 77+/-10% of MAP (Maximal Aerobic Power), oxygen uptake 3788+/-327 mL min(-1) (82.8% of VO2max), heart rate 162+/-13 beats min(-1) (92% of maximal HR) and ventilation 112.8+/-20.8 L min(-1). MAS was correlated with performance in swimming sector (r = 0.944; P < 0.05). Despite intake 1.08+/-0.44 L of a solution with 8% of sugars, a significant loss of body weight (2.80%; P < 0.01) was observed. Changes in cycling power, speed and frequency, especially towards the end of the effort, were also found. By contrast, differences in lactate concentration and in cardiorespiratory or metabolic variables between the end of the swimming sector and the end of the first transition did not appear. In conclusion, this study remarks different relative intensities in cycling and swimming sectors. The observed loss of body weight does not modify pedalling economy in national and international-level athletes during the cycling sector, where effort intensity adapts itself to the one found in individual lactate threshold. However, changes in competition tactics and other effects, such as drafting in swimming and cycling, could alter the intensities established in this study for each sector.

[Muscular energetic metabolism study in athletes using 31P-MRS]. / Estudo do metabolismo energético muscular em atletas por 31P-ERM.

BACKGROUND: The aim of this study was to characterize the muscular reservoirs of phosphorilated energetic components of athletes using 31P-MRS. METHODS: The sample was formed by 14 elite athletes from the Center for High Sportive Performance (CAR, Sant Cugat del Vallés, Spain). The pattern of the phosphorilated metabolites was measured from the muscle vastus medialis by 31P-MRS. Oral supplementation of 20 g of Creatine monohydrate was given during 14 days. Two groups of athletes were formed according to their physical characteristics (weight, height, body mass index, maximum O2 uptake). The first group received a placebo (maltodextrine), while the second group received a diet of creatine supplement. The exercise was performed inside the resonance tunnel with a frequency of 60 RPM with both legs. RESULTS: The results showed that significant decrease occurred in phosphocreatine (PCr), inorganic phosphate (Pi) and intracellular pH after supplementation. CONCLUSION: It was concluded that the exercise performed by the long distance runners recruited in this study, detected by 31P-MRS, reduced the consumption of PCr during exercise owing to creatine supplementation diet.

Estudo do metabolismo energético muscular em atletas por 31P-ERM / Muscular energetic metabolism study in athletes by 31P-MRS

OBJETIVO: Caracterizar as reservas energéticas de metabólitos fosforilados no músculo esquelético de atletas mediante 31P-ERM. MÉTODOS: Amostra deste estudo foi formada por 14 atletas de alto nível do Centro de Alto Rendimento Esportivo (CAR, Sant Cugat del Vallés, Espanha). O padrão de metabólitos fosforilados foi medido no músculo vasto medial por 31P-ERM. A suplementação oral foi realizada durante 14 dias, na forma de 20g de monohidrato de creatina. Os atletas foram determinados conforme as suas características físicas (peso, altura, índice de massa corporal (IMC), consumo máximo de oxigênio (VO2 Max.) em dois grupos: placebo (maltodextrina) e suplementação com creatina. O protocolo de exercício foi realizado no interior do túnel de ressonância (160 x 52 cm), a 60 ciclos por minuto para ambas as pernas. RESULTADOS: Os resultados demonstraram um aumento significativo da fosfocreatina (PCr) durante o exercício, após o período de suplementação, denotando uma redução do seu consumo no grupo que recebeu suplementação com creatina; não houve diminuição significativa do pH intracelular e fosfato inorgânico após a suplementação. CONCLUSÃO: O protocolo de exercício realizado pelos fundistas no Centro de Diagnóstico de Pedralbes permitiu detectar mediante 31P-ERM, no grupo que foi suplementado com creatina, uma diminuição do consumo de PCr durante os períodos de exercício.

Efecto de la suplementación oral con monohidrato de creatina en el metabolismo energético muscular y en la composición corporal de sujetos que practican actividad física / Efect of supplementation with monohydrate creatine on the muscular energetic metabolism and in corporal composition of subject that practice physical activity

Nos interesó investigar el efecto de la suplementación oral de creatina en el metabolismo energético muscular de sujetos activos por medio de espectroscopia de resonancia magnética de fósforo (31P-RMN) y pruebas de rendimiento en laboratorio. Se estudiaron 13 varones, fisicamente activos de 23,1±5,3 años (media±sd), los sujetos se distribuyeron de manera aleatoria en tres grupos: placebo (grupo 1, n=4), suplementación de creatina (grupo 2, n=4) y suplementación de creatina más carbohidrato (grupo 3, n=5). La suplementación se efectuó por vía oral, durante 12 días en forma de: 20 g de fibra de guisante (grupo 1), 20 g de monohidrato de creatina (grupo 2) y 20 g de monohidrato de creatina más 5,7 g de maltodextrina y 9 g de fructosa (grupo 3). La dosis diaria se repartió en cuatro tomas iguales, disueltas en un vaso de agua. La prueba de rendimiento en laboratorio consistió en ejercicio de pedaleo sobre una bicicleta de freno mecánico a 120 rpm (fuerza de frenado igual al 30 por ciento de la fuerza máxima teórica determinada mediante una prueba previa de fuerza-velocidad) llevado hasta el agotamiento seguido, tras 1 minuto de pausa pasiva, se realizó un según ejercicio de 10 s de pedaleo (fuerza de frenado igual al 50 por ciento de la fuerza máxima) a máxima velocidad. Resultados: la relación PCr/ATP aumentó significativamente en los grupos 2 y 3. Esta relación no varió significativamente entre los grupos 2 y 3. Ambos grupos se consideraron conjuntamente como grupo de suplementación para el análisis de los resultados del rendimiento en el laboratorio. El grupo suplementado mejoró en forma significativa la velocidad máxima (11,5 por ciento), la potencia máxima (12 por ciento), y la potencia media (15,7 por ciento) desarrolladas durante el esfuerzo de 10 segundos. Se concluye que la suplementación con creatina incrementa el contenido muscular de fosfocreatina (PCr) y aumenta el rendimiento en una prueba de velocidad realizada en 10 segundos después de un esfuerzo extenuante.