Pacing and Body Weight Changes During a Mountain Ultramarathon: Sex Differences and Performance

The study was aimed at comparing pacing adopted by males and females in a 107-km mountain ultramarathon and assessing whether pacing-related variables were associated with intracompetition body weight changes and performance. Forty-seven athletes (29 males; 18 females) were submitted to a cardiopulmonary exercise test before the race. Athletes were also weighted before the start of the race, at three midpoints (33 km, 66 km and 84 km) and after the race. Pacing was analyzed using absolute and relative speeds and accelerometry-derived sedentary time spent during the race. Results showed that females spent less sedentary time (4.72 ± 2.91 vs. 2.62 ± 2.14%; p = 0.035; d = 0.83) and displayed a smaller body weight loss (3.01 ± 1.96 vs. 4.37 ± 1.77%; p = 0.048; d = 0.77) than males. No significant sex differences were revealed for speed variability, absolute and relative speed. In addition, finishing time was correlated with: speed variability (r = 0.45; p = 0.010), index of pacing (r = -0.63; p < 0.001) and sedentary time (r = 0.64; p < 0.001). Meanwhile, intracompetition body weight changes were related with both the absolute and relative speed in the first and the last race section. These results suggest that females, as compared with males, take advantage of shorter time breaks at aid stations. Moreover, performing a more even pacing pattern may be positively associated with performance in mountain ultramarathons. Finally, intracompetition body weight changes in those races should be considered in conjunction with running speed fluctuations

Ultra Trail Performance is Differently Predicted by Endurance Variables in Men and Women

The study aimed to assess the relationship between peak oxygen uptake, ventilatory thresholds and maximal fat oxidation with ultra trail male and female performance. 47 athletes (29 men and 18 women) completed a cardiopulmonary exercise test between 2 to 4 weeks before a 107-km ultra trail. Body composition was also analyzed using a bioelectrical impedance weight scale. Exploratory correlation analyses showed that peak oxygen uptake (men: r=–0.63, p=0.004; women: r=–0.85, p < 0.001), peak speed (men: r=–0.74, p < 0.001; women: r=–0.69, p=0.009), speed at first (men: r=–0.49, p=0.035; women: r=–0.76, p=0.003) and second (men: r=–0.73, p < 0.001; women: r=–0.76, p=0.003) ventilatory threshold, and maximal fat oxidation (men: r=–0.53, p=0.019; women: r=–0.59, p=0.033) were linked to race time in male and female athletes. Percentage of fat mass (men: r=0.58, p=0.010; women: r=0.62, p= 0.024) and lean body mass (men: r=–0.61, p=0.006; women: r=–0.61, p=0.026) were also associated with performance in both sexes. Subsequent multiple regression analyses revealed that peak speed and maximal fat oxidation together were able to predict 66% of male performance; while peak oxygen uptake was the only statistically significant variable explaining 69% of the variation in women’s race time. These results, although exploratory in nature, suggest that ultra trail performance is differently predicted by endurance variables in men and women

Inspiratory and Lower-Limb Strength Importance in Mountain Ultramarathon Running. Sex Differences and Relationship with Performance

The study was aimed at comparing lower-limb strength and respiratory parameters between male and female athletes and their interaction with performance in a 107 km mountain ultramarathon. Forty seven runners (29 males and 18 females; mean ± SD age: 41 ± 5 years) were enrolled. Lower-limb strength assessment comprised a squat jump test, an ankle rebound test, and an isometric strength test. Respiratory assessment included pulmonary function testing and the measurement of maximal inspiratory pressure. Male athletes performed largely better in the squat jump (26 ± 4 vs. 21 ± 3 cm; p < 0.001; d = 1.48), while no sex differences were found in the other two lower-limb tests. Concerning the respiratory parameters, male athletes showed largely greater values in pulmonary expiratory variables: forced vital capacity (5.19 ± 0.68 vs. 3.65 ± 0.52 L; p < 0.001; d = 2.53), forced expiratory volume in 1 s (4.24 ± 0.54 vs. 2.97 ± 0.39 L; p < 0.001; d = 2.69), peak expiratory flow (9.9 ± 1.56 vs. 5.89 ± 1.39 L/min; p < 0.001; d = 2.77) and maximum voluntary ventilation in 12 s (171 ± 39 vs. 108 ± 23 L/min; p < 0.001; d = 1.93); while no sex differences were identified in maximal inspiratory pressure. Race time was associated with ankle rebound test performance (r = −0.390; p = 0.027), isometric strength test performance (r = −0.349; p = 0.049) and maximal inspiratory pressure (r = −0.544; p < 0.001). Consequently, it seems that athletes competing in mountain ultramarathons may benefit from improving lower-limb isometric strength, ankle reactive strength and inspiratory muscle strength. Nevertheless, further interventional studies are required to confirm these exploratory results. In addition, the fact that the magnitude of the sex difference for isometric strength was minor, as compared with the other strength tests, could represent one of the factors explaining why the performance gap between males and females is reduced in ultramarathons

The week after running a marathon: effects of running vs elliptical Training vs resting on neuromuscular performance and muscle damage recovery

Our aim was to compare the effects of two exercise modalities vs resting on the time course of neuromuscular performance and muscle damage recovery during the week after running a marathon. Sixty-four finishers from a road marathon completed the study (54 men and 10 women; 39 ± 4 years; 3 h 35 min ± 21 min). The day before the race, within 15 min after finishing the marathon and at 24, 48, 96, 144 and 192 h postrace, lactate dehydrogenase and creatine kinase were analysed. Participants also performed a squat jump (SJ) test before and after the marathon and at 48, 96 and 144 h postrace. On their arrival to the finish line, participants were randomized into one of the three intervention groups: running (RUN), elliptical training (ELIP) and resting recovery (REST). RUN and ELIP groups exercised continuously for 40 min at a moderate intensity (95–105% of the HR corresponding to the first ventilatory threshold) at 48, 96 and 144 h after the marathon. Neither ‘Intervention’ factor nor ‘Intervention x Time’ interaction effects were revealed for muscle damage blood markers (p > 0.05). On the other hand, RUN group evidenced an enhancement in SJ performance 96 h post-marathon as compared with REST group (108.29 ± 10.64 vs 100.58 ± 9.16%, p = 0.020, d = 0.80). Consequently, return to running at 48 h post-marathon does not seem to have a negative impact on muscle damage recovery up to eight days post-race and it could be recommended in order to speed up neuromuscular recovery

Anàlisi de l’elecció de la cama d’atac predominant en la prova de 400 metres tanques dels XIII Campionats del Món d’Atletisme Daegu 2011

Objectius: Analitzar la utilització d’una o altra cama com a cama d’atac predominant en atletes de 400 metres tanques d’alt nivell. Mètode: L’estudi és descriptiu de tall transversal. Es van estudiar totes les curses de 400 metres tanques dels 72 participants (34 homes i 38 dones) en els XIII Campionats del Món d’Atletisme Daegu 2011 mitjançant la gravació en vídeo des de la tribuna principal del Daegu Stadium de les 18 curses de 400 metres tanques disputades i la posterior anàlisi mitjançant l’aplicació informàtica Kinovea 0.8.4. Resultats: Per atletes, en el total de les curses masculines, la cama d’atac predominant va ser l’esquerra, amb el 63,6 % (42 atletes), i amb la cama dreta va haver-hi el 34,8 % (23 atletes). Només en un cas hi havia un equilibri entre esquerra i dreta. A la final va haver-hi el 75 % (6 atletes) la cama predominant d’atac dels quals va ser l’esquerra. Quant a les dones, la cama d’atac predominant va ser l’esquerra, amb el 48,6 %, seguida de la cama dreta, amb el 41,4 %, i per al 10 % hi havia un equilibri de les dues. A la final, en canvi, la cama predominant d’atac va ser la dreta, amb el 87,5 % (7 atletes), pel 12,5 % de l’esquerra (1 sola atleta). Es van trobar diferències significatives (p = 0,018) en la mitjana de temps finals dels atletes masculins segons quina fos la seva cama d’atac. Conclusions: La majoria dels atletes ataquen les tanques amb dreta i esquerra en algun moment de la cursa, la qual cosa obliga al domini tècnic bilateral. La cama d’atac més utilitzada és l’esquerra, encara que en menor mesura en el cas de les dones. Per primera vegada en una gran competició, 7 de les 8 finalistes tenen la cama dreta com a cama predominant.Objectives: to analyse use of either leg as the predominant lead leg by high level 400 m hurdlers. Method: this is a crosssectional descriptive study. We studied all the 400 m hurdles races of the 72 participants (34 men and 38 women) at the 13th World Athletics Championships Daegu 2011 by recording video from the Daegu Stadium grandstand of the eighteen 400 m hurdles races run and subsequently performing analysis using the Kinovea 0.8.4 computer application. Results: by athletes, in the total men’s races the predominant lead leg was the left one at 63.6% (42 athletes) while it was the right leg in 34.8% of cases (23 athletes). Only in one case was there a balance between left and right. In the final the predominant lead leg for 75% or 6 of the athletes was the left one. As for women, the predominant lead leg was the left one at 48.6% followed by the right leg at 41.4% and 10% had a balance between the two. In the final, however, the predominant lead leg was the right one at 87.5% (7 athletes) compared to 12.5% for the left leg (just 1 athlete). Significant differences (p = 0.018) were found in the mean final time for men athletes depending on which their lead leg was. Conclusions: most athletes lead the hurdles with both left and right legs at some point in the race which means they need bilateral technical mastery. The leg most used to lead the hurdles is the left one, albeit to a lesser extent in the case of women. For the first time in a major competition, 7 of the 8 finalists had their right leg as their predominant leg

Perfil del rendimiento en los métodos de competición del corredor de 800 m: análisis de la distribución del ritmo y la zancada

El rendimiento deportivo, está condicionado por pequeños detalles que pueden alejar al deportista de sus objetivos. En las carreras de atletismo las diferencias entre los primeros clasificados son muy exiguas. Dentro de las pruebas de medio fondo, uno de los factores que deben considerarse son los diferentes planteamientos tácticos. En el caso del 800 m podríamos diferenciar entre “carreras a marca” y “carreras de campeonato”. Estrategias que tienen que ver la distribución del ritmo o regulación energética y que constituyen uno de los factores que determinaran el resultado final de una competición. Con el objeto de profundizar en los entrenamientos que desarrollan las necesidades específicas de la competición en los 800 m de las carreras a marca, se han analizado dos métodos clásicos de entrenamiento de la velocidad-resistencia como el Ritmo Competición (RC) y las Series Rotas (SR), buscando aplicaciones prácticas que permitan hacer más eficaces los entrenamientos. En el estudio han participado 19 atletas varones de nivel nacional e internacional, divididos en dos categorías: Categoría Deportiva (9 atletas Juvenil-Junior [GB] y 10 atletas Promesa-Senior [GA]) y Categoría Nivel de Rendimiento (9 atletas de Nivel 1 [N1] compuesta por corredores que durante la temporada 2009-2010 habían cosechado méritos para estar en el Campeonato de España de su categoría y 10 atletas de Nivel 2 [N2] compuesta por atletas que no cosecharon este mérito. Cada deportista realizó dos sesiones prácticas para cada uno de los métodos de entrenamiento: [(RC: 1 x 600 m; Intensidad = velocidad competitiva (VC); SR: 2 x 4 x 200 m; Int = 102% de la VC. Recuperación = 30 s. Pausa = 15 min)]. Con el fin de determinar el grado de exigencia de ambos esfuerzos, se registró la producción de lactato, el esfuerzo percibido y la frecuencia cardiaca. Un primer análisis se centró en la distribución rítmica del esfuerzo, considerando los 3 parciales de 200 m del RC y cada una de las repeticiones de las SR (8 en total). Posteriormente, el estudio se centró en los parámetros que determinan la zancada del corredor: longitud y frecuencia. En este caso también se analizaron todos los parciales de 200 m del RC, y las repeticiones de las SR donde se registraron diferencias significativas en la distribución rítmica (primera y última repetición de cada serie). La investigación se llevó a cabo con un diseño mixto. Por un lado se realizó un diseño intragrupo para estudiar la evolución tanto de la distribución rítmica (evolución de los tiempos) como de la zancada (longitud y frecuencia). Y por otro lado se realizó un diseño intergrupo para estudiar las diferencias que pudieran existir entre agrupaciones en función de la categoría deportiva (edad) y nivel de rendimiento. Los resultados muestran un incremento significativo (p<0.005) de los tiempos de los parciales de 200 m del RC considerando la muestra completa relacionado con un descenso significativo (p<0.005) del 4.90% de la longitud de zancada, con valores de 2.04±0.12 m en el primer parcial (RC1) y 1.94±0.13 m en el último parcial (RC3). En cuanto a la frecuencia de zancada, se encontraron valores que oscilaron entre 3.54±0.16 y 3.40±0.18 Hz para el RC1 y RC3 respectivamente, con diferencias significativas (p<0.005) y una pérdida del 3.95%; destacando la ausencia de significación entre los dos últimos parciales (RC2 y RC3). En el caso de la SR, aunque también se dio una tendencia a incrementarse los tiempos, conviene destacar que esas pérdidas no fueron lineales, a diferencia del RC, en la comparación por pares (ajuste de Bonferroni). Sólo la primera repetición de cada serie fue más rápida que el resto (p<0.005), no registrándose significación entre el resto de repeticiones de una misma serie con respecto a la repetición anterior o posterior. Además, gracias al efecto de la pausa (15 min), se mejoró (p<0.005) el tiempo de la primera repetición de la segunda serie con respecto a la última de la primera serie. En las SR también se produjeron pérdidas (5.42%; p<0.005) de longitud de zancada en las repeticiones analizadas (2.03±0.12 y 1.92±0.14 m para la primera y última repetición). Los valores alcanzados en la frecuencia de zancada en las SR se situaron entre 3.53±0.22 Hz en la primera repetición y 3.39±0.18 Hz en la última (p<0.005), equivalente al 3.97% de pérdida. Los lactatos alcanzados en este trabajo, próximos a los que se alcanzan en competición, hablan de la exigencia de los métodos (13.58±1.82 mmol/l para el RC; 12.25±2.03 y 15.42±1.16 mmol/l para la 1ª y 2ª serie de las SR respectivamente). Estos resultados nos llevan a concluir que el RC es adecuado para mejorar la distribución rítmica del primer 400 m en las carreras a marca de 800 m. De forma complementaria, las SR desarrollan más la parte central del 800 m (2º y 3er parcial de 200 m). Ambos métodos entrenan la resistencia a la velocidad específica en su parte final, suponiendo una aproximación al tramo final del estímulo competitivo. Por otro lado, el principal responsable del incremento de los tiempos fue la reducción significativa de la longitud de zancada a medida que evoluciona el esfuerzo. La menor pérdida de la frecuencia, con ausencia de significación en los dos últimos parciales del RC, puede relacionarse con una estrategia para compensar la pérdida inevitable de longitud de zancada asociada a la disminución de la fuerza por el efecto de la fatiga. En cuanto a las agrupaciones establecidas, la categoría deportiva registró diferencias en el comportamiento de la distribución rítmica, con una estrategia más relacionada con lo que sucede en las pruebas a marca de 800 m (donde se incrementan los tiempos de los parciales a medida que avanza la prueba) en el caso del GA (mayor edad-experiencia). Por lo que respecta a la longitud de zancada ambos métodos registraron comportamientos similares con un descenso significativo de longitud conforme avanza la serie, siendo el GA quien alcanzó valores más elevados (p<0.05) en comparación con GB. Por el contrario, los valores de frecuencia de zancada fueron más elevados en los atletas más jóvenes (GB) con un descenso de este valor menos acusado a medida que evoluciona el método. En cuanto al nivel de rendimiento tanto la distribución rítmica como la longitud de zancada (con valores más elevados para N1) fue similar en ambas agrupaciones. Finalmente, en la frecuencia de zancada se observó como el N2 realizó mayores valores de frecuencia al inicio de cada una de las series, tratando de compensar niveles más bajos de longitud de zancada, circunstancia que probablemente provocó que las pérdidas fueran mayores en el tramo final de las mismas en comparación con N1

Muscle cramping in the marathon: dehydration and electrolyte depletion vs. muscle damage

Our aim was to compare dehydration variables, serum electrolytes, and muscle damage serum markers between runners who suffered exercise-associated muscle cramps (EAMC) and runners who did not suffer EAMC in a road marathon. We were also interested in analyzing race pacing and training background. Nighty-eight marathoners took part in the study. Subjects were subjected to a cardiopulmonary exercise test. Before and after the race, blood and urine samples were collected and body mass (BM) was measured. Immediately after the race EAMC were diagnosed. Eighty-eight runners finished the marathon, and 20 of them developed EAMC (24%) during or immediately after the race. Body mass change, post-race urine specific gravity, and serum sodium and potassium concentrations were not different between crampers and noncrampers. Conversely, runners who suffered EAMC exhibited significantly greater post-race creatine kinase (464.17 ± 220.47 vs. 383.04 ± 253.41 UI/L, p = 0.034) and lactate dehydrogenase (LDH) (362.27 ± 72.10 vs. 307.87 ± 52.42 UI/L, p = 0.002). Twenty-four hours post-race also values of both biomarkers were higher among crampers (CK: 2,438.59 ± 2,625.24 vs. 1,166.66 ± 910.71 UI/L, p = 0.014; LDH: 277.05 ± 89.74 vs. 227.07 ± 37.15 UI/L, p = 0.021). The difference in the percentage of runners who included strength conditioning in their race training approached statistical significance (EAMC: 25%, non-EAMC: 47.6%; p = 0.074). Eventually, relative speed between crampers and noncrampers only differed from the 25th km onward (p < 0.05). Therefore, runners who suffered EAMC did not exhibit a greater degree of dehydration and electrolyte depletion after the marathon but displayed significantly higher concentrations of muscle damage biomarkers

Quantifying performance impairment, specificity and fatigue in young soccer professionals: UIRFIDE Soccer test vs. Bangsbo Test

BACKGROUND: Repeated-acceleration-ability (RAA) has been gaining more and more importance in modern soccer over repeated-sprint-ability (RSA). This study aims to improve knowledge about RAA training and testing in youth, looking for increasing fatigue, specificity and complexity as compared to traditional RSA tests. It also ascertains for appropriate fatigue indicators. METHODS: Ten professional soccer players (17.6 +/- 1.17 years) performed Bangsbo Test (BT), and one week later, UIRFIDE Soccer Test (UST), a complex test comprising three sections, repeated 6 times. USTA assesses RAA without the ball (30m:10m lineal run+2x10m shuttle run/5s) whilst USTB assesses technical skill under fatigue (40m dealing with the ball). USTC includes 1-CMJ. Five seconds of recovery are interspersed between actions and 15 s between sections. Physiological responses, together with performance decrement (DEC) and Fatigue Index (FI), were analyzed to compare performance impairment (BT vs. USTA) and overall fatigue (BT vs. UST). 95% CI and correlation analysis were included. RESULT S: Heart rate was higher for UST (P=0.011), despite similar lactate and RPE. Less total time and linear-sprint patterns explain higher velocities in BT [(20.49-21.18) vs. (16.52-18.48) km/h], with significantly lower fatigue (DEC%: 2.41-4.62 vs. 5.59-12.91; FI%: 4.18-7.66 vs. 8.54-21.03). FI was less homogeneous than DEC, but reflected better individual differences. Both indexes kept within stability limits and were associated (r>0.80; P<0.005), while best performance showed no association with fatigue. CONCLUSIONS: Age does not prevent from performing maximally the UST, closer to game specificity than BT. FI helps to identify individual differences in performance impairment, which is important when reproducing the worst scenario of a soccer game

Dicellomus Hall, 1871 (Brachiopoda) : designation of a type-species under the plenary powers

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