Anthropometric Characteristics, Training Intensity Distribution, Physiological Profile and Performance of an Elite Trail Runner: A Longitudinal Case Study / Características Antropométricas, Distribución de la Intensidad del Entrenamiento, Perfil Fisiológico y Rendimiento de un Corredor de Montaña de Élite: Un Estudio de Caso Longitudinal

SUMMARY: Trail running (TR), an extreme endurance sport, presents unique challenges due to the variety of terrain and distances, where physiological capacity and body composition have been considered better predictors of performance. This longitudinal case study examines the impact of training intensity distribution (TID) on an elite trail runner's physiological profile and performance over four years. Two TID models were implemented: polarized (POL) and pyramidal (PYR). Physiological assessments included maximal oxygen consumption (VO2max), lactate thresholds (LT1 and LT2), and anthropometric characteristics. The training was classified according to the 3-zone intensity model (zone 1: below the first lactate threshold; zone 2: between the first and second lactate threshold; zone 3: above the second lactate threshold). During the four years, the average TID distribution was 75 % zone 1, 18 % zone 2, and 7 % zone 3. Physiological capacity increased by 7.14 % (14 to 15 km/h) for velocity at LT1 (vLT1) and 8.13 % (16 to 17.3 km/h) for velocity at LT2 (vLT2). The most significant increases were observed during the second year when the percentage of training time in zone 1 was lower (65 %) and in zone 2 greater (30 %) than those reported in other years. Consequently, vLT1 and vLT2 increased by 3.5 % (from 14.1 to 14.6 km/h) and 3.6 % (from 16.5 to 17.1 km/h), respectively. In conclusion, this case study revealed that emphasizing training in zone 2 (moderate intensity) and increasing the training load significantly improved performance at lactate thresholds. Despite modifying body composition, no influence on improving endurance performance was observed. These findings underscore the importance of TID in elite trail runners and highlight the potential to optimize physiological adaptations and performance outcomes.

Trail running (TR), un deporte de resistencia extrema, presenta desafíos únicos debido a la variedad de terrenos y distancias, donde la capacidad fisiológica y la composición corporal se han considerado mejores predictores del rendimiento. Este estudio de caso longitudinal examina el impacto de la distribución de la intensidad del entrenamiento (TID) en el perfil fisiológico y el rendimiento de un corredor de montaña de élite durante cuatro años. Se implementaron dos modelos TID: polarizado (POL) y piramidal (PYR). Las evaluaciones fisiológicas incluyeron el consumo máximo de oxígeno (VO2max), los umbrales de lactato (LT1 y LT2) y las características antropométricas. El entrenamiento se clasificó según el modelo de intensidad de 3 zonas (zona 1: por debajo del primer umbral de lactato; zona 2: entre el primer y segundo umbral de lactato; zona 3: por encima del segundo umbral de lactato). Durante los cuatro años, la distribución TID promedio fue 75 % zona 1, 18 % zona 2 y 7 % zona 3. La capacidad fisiológica aumentó un 7,14 % (14 a 15 km/h) para la velocidad en LT1 (vLT1) y un 8,13 % (16 a 17,3 km/h) para velocidad en LT2 (vLT2). Los incrementos más significativos se observaron durante el segundo año cuando el porcentaje de tiempo de entrenamiento en la zona 1 fue menor (65 %) y en la zona 2 mayor (30 %) que los reportados en otros años. En consecuencia, vLT1 y vLT2 aumentaron un 3,5 % (de 14,1 a 14,6 km/h) y un 3,6 % (de 16,5 a 17,1 km/h), respectivamente. En conclusión, este estudio reveló que enfatizar el entrenamiento en la zona 2 (intensidad moderada) y aumentar la carga de entrenamiento mejoró significativamente el rendimiento en los umbrales de lactato. A pesar de modificar la composición corporal, no se observó influencia en la mejora del rendimiento de resistencia. Estos hallazgos subrayan la importancia del TID en los corredores de trail de élite y resaltan el potencial para optimizar las adaptaciones fisiológicas y los resultados de rendimiento.

Training intensity distribution on running time in amateur endurance runners: a scoping review / Distribución de intensidades de entrenamiento sobre el tiempo de carrera en corredores recreativos de resistencia: revisión de alcance

Problem: Intensity in endurance training is important for improving race time; its optimal handling in amateur runners has not been extensively studied. The polarized training intensity distribution (TID) model emerges as a possibility to reduce race time; however, effect of this model remains to be demonstrated compared to other TID models. Objective: The objective of this study is to explore the current state of the evidence and its the gaps, according to the effect of the polarized TID model on race time in amateur runners compared to other TID models. Method: A scoping review without date restrictions was carried out in PubMed, EBSCO, SciELO, LILACS, and Google Scholar. Randomized controlled studies, quasi-experimental studies, and case studies, which comprise polarized TID model in amateur runners on race time, were include. Results: Five studies evaluated the effect on running time using the polarized TID model compared to other models in amateur runners; four of them did not show differences between groups in the race times in two, five, and ten km. Only one study showed significant diferences in the race time at 21 km. Conclusions: The model with polarized TID did not show significant differences in race time compared to other models, except for a case report in which the polarized TID was higher by 21 km compared to the threshold TID: 1 hour. 20 min. 22 seconds and 1 hour. 26 min. 34s, respectively. The scarce evidence found, the heterogeneity in the distances in the evaluated race time, the distribution of zones in the same TID, the duration of the interventions, and the monitoring of the loads, are the main limitations found in the studies. The polarized TID could contribute to adherence, lower perception of effort, and injury prevention. However, this must be tested in future studies.

Problema: La intensidad en el entrenamiento de la resistencia es importante para mejorar el tiempo de carrera; su manipulación óptima en corredores recreativos no ha sido estudiada ampliamente. El modelo de distribución de intensidad del entrenamiento (DIE) polarizado emerge como posibilidad para reducir el tiempo de carrera. Sin embargo, falta demostrar su efecto comparado con otros modelos de DIE. Objetivo: Explorar el estado actual de la evidencia científica y sus vacíos respecto al efecto del modelo de DIE polarizado sobre el tiempo de carrera en corredores recreativos, en comparación con otros modelos de DIE. Método: Se realizó una revisión de alcance sin restricción de fechas en PubMed, EBSCO, SciELO, LILACS y Google Scholar. Se incluyeron estudios controlados aleatorios, estudios cuasiexperimentales y estudios de caso, que tuvieran como DIE el modelo polarizado en corredores recreativos sobre el tiempo de carrera. Resultados: Cinco estudios evaluaron el efecto en el tiempo de carrera usando el modelo de DIE polarizado comparado con otros modelos en corredores recreativos; cuatro de ellos no mostraron diferencias entre grupos en los tiempos de carrera en dos, cinco y diez km. Solo un estudio mostró diferencias significativas en el tiempo de carrera en 21 km. Conclusiones: El modelo con DIE polarizado no mostró diferencias significativas en el tiempo de carrera comparado con otros modelos, a excepción de un reporte de caso en el cual la DIE polarizado fue superior en 21 km comparado la DIE umbral: 1 hora. 20 min. 22 s y 1 hora. 26 min. 34 s, respectivamente. La escasa evidencia encontrada, la heterogeneidad en las distancias en el tiempo de carrera evaluado, la distribución de zonas en una misma DIE, la duración de las intervenciones y la monitorización de las cargas son las principales limitaciones encontradas en los estudios. La DIE polarizado podría contribuir a la adherencia, a una menor percepción del esfuerzo y a la prevención de lesiones. No obstante, esto debe ser probado en estudios futuros.

Respostas neuromusculares ao treinamento resistido de alta intensidade (HIRT) / Neuromuscular responses tohigh intensity resistance train-ing (HIRT) / Respuestas neuromusculares al entrenamiento de resistencia de alta intensidad (HIRT)

O presente estudo buscou avaliar respostas neuromusculares ao treinamento resistido de alta intensidade (HIRT). Doze universitários do sexo masculino com idade de 21 ± 3anos, realiza-ram o protocolo HIRT, que é caracterizado por pausas de 20 segundos entre as repetições. Posteriormente, foi realizado salto vertical (SV), horizontal (SH), arremesso de Medicine-Ball (MedBall) e força de pressão manual (FPM), antes, depois eapós 24h e 48h, o HIRT. Os sal-tos apresentaram significância nos períodos PRÉ e PÓS-SV (p=0,01), SH (p=0,02). Entretan-to, arremesso de MedBall e FPM não demonstraram diferenças significativas. Especula-se que o HIRT afete de modo agudo a potência de membros inferiores, mas não a de superiores. Porém, o período de 24 horas parece ser suficiente para a recuperação.

The present study aimed to evaluate neuromuscular responses to high intensity resistance training (HIRT). Twelve male university students aged 21 ± 3 years, in which they performed the HIRT protocol, which is characterized by pauses of 20sec between repetitions. Subse-quently, horizontal (SH) vertical jumps (SV), Medicine Ball (MedBall) and manual pressure force (FPM) were performed before, after and after 24h and 48h the HIRT. The jumps showed significance in the periods PRÉ and POS SV (p = 0.01), SH (p = 0.02). However, MedBall and FPM throw did not show significant difference. HIRT acutely affects the poten-cy of lower limbs, but not of upper limbs. However, the 24-hour period seems to be sufficient for recovery.

El presente estudio buscó evaluar respuestas neuromusculares al entrenamiento resistido de alta intensidad (HIRT). Doce universitarios varones con edad de 21 ± 3 años, en el que reali-zaron el protocolo HIRT, que se caracteriza por pausas de 20seg entre repeticiones. Se reali-zaron saltos verticales (SV) horizontales (SH), lanzamiento de Medicina-Ball (MedBall) y fuerza de presión manual (FPM), antes, después y después de 24h y 48h el HIRT. Los saltos presentaron significancia en los períodos PRÉ y PÓS SV (p = 0,01), SH (p = 0,02). Sin em-bargo, el lanzamiento de MedBall y FPM no mostró diferencia significativa. El HCA afecta de forma aguda a la potencia de miembros inferiores, pero no de superiores. Sin embargo, el período de 24h parece suficiente para la recuperación.

Effects of the intensity of lower limb training after stroke / 中华物理医学与康复杂志

Objective To investigate the effects of lower limb training at different intensities on the recovery of walking function after stroke.Methods Thirty-six stroke patients were randomly divided into a 40-minutes of training group,an 80-minutes of training group and a 120-minutes of training group.Because of three missing followup cases,the final numbers of cases were 12,11 and 10 cases respectively.All of the patients received lower limb training based on regular rehabilitation therapy,but at the three different intensities:40 minutes,80 minutes or 120 minutes a day,five days per week,for 4 weeks.Walking function was assessed using the Holden functional ambulation categories (FACs) and the Fugl-Meyer assessment (FMA).These were carried out before treatment,and after two and four weeks of treatment.Results Before treatment,the average FACs of the three groups were (1.83 ±0.94),(1.73 ± 1.01) and (1.80 ± 1.03) respectively.Their average FMA scores were (19.17 ±5.52),(23.00±4.71) and (19.40 ±7.90).After two weeks of treatment,the average FAC in the 120-minutes training group was (3.30 ± 0.48),significantly higher than in the 40-minutes training group.After four weeks the average FACs in the 40-minutes,80-minutes and 120-minutes training groups were (2.67 ± 0.65),(3.18 ± 0.60) and (3.80 ±0.42) respectively.The differences between the 120-minutes group and the 80-minutes group as well as between the 80-minutes group and the 40-minutes training group were statistically significant.The average FMA scores of the three groups after four weeks were (25.08±4.46),(28.64±3.56) and (25.90±5.19) respectively.All the differences were significant compared with pre-treatment.There were no significant differences in FMA scores among the three groups after two weeks or four weeks of treatment.Before treatment,the proportion of patients able to walk independently in the 40-minutes,80-minutes and 120-minutes training groups were 16.7％,18.2％ and 20.0％.After two weeks the proportions had risen to 33.3％,36.4％ and 100％ respectively,so the results in the 120-minutes training group were significantly better.After four weeks of treatment the proportions of the three groups were 58.3％,90.9％ and 100％.All these improvements were significant compared with pre-treatment,but when compared with the 80-minutes training group,neither of the others showed a significant difference.Conclusions Intensive training can accelerate the recovery of walking function of patients after stroke and promote their ability to participate in daily activities.

Cholesterol metabolism in rat after two intensities of treadmill exercise training / 体力科学

In this study, we investigated the effect of exercise training on serum and liver chblesterol levels and on biosynthesis of liver cholesterol in rats. The training was carried out at low [Low-Ex, 60% max O<SUB>2</SUB> consumption (VO<SUB>2</SUB>) ] and high (High-Ex, 75% max VO<SUB>2</SUB>) intensities for 16 weeks. The energy expenditure was adjusted to be equivalent. The succinate dehydrogenase activities of gastrocnemius muscle in the Low-Ex group and High-Ex group were higher than that of control, 36% and 109% (p<0.05) respectively. The levels of total and high density lipoprotein cholesterol in serum were 14-26% lower than those of control, but no difference was detected between the trained groups. The activity of HMG-CoA reductase in liver microsome was significantly higher than that of control for both trained groups. However, the stimulation of this enzyme activity was not changed by training intensity.