Economía de carrera y rendimiento. Esfuerzos de alta y baja intensidad en el entrenamiento y calentamiento. Revisión bibliográfica / Running economy and performance. High and low intensity efforts during training and warm-up. A bibliographic review

La economía de carrera ha crecido en importancia en la literatura científica como factor de rendimiento en corredores de fondo y medio fondo tanto de alto nivel como recreacional. Los atletas entrenados son más económicos que aquellos no entrenados, mostrando que es una variable que se mejora con el entrenamiento. Un factor clave en la selección del entrenamiento de resistencia es la intensidad del esfuerzo a realizar, principalmente caracterizado por dos métodos de entrenamientos como son el interválico y el continuo. En corredores de nivel recreacional, existe cierta controversia en relación a qué intensidades son las óptimas para mejorar la economía de carrera, recomendándose la realización de entrenamiento periodizado y exista una lógica relación entre entrenamiento de alta y baja intensidad. Recomendamos la inclusión de 2-3 sesiones semanales de entrenamiento interválico, compensado con entrenamiento continuo. En cuanto a los corredores entrenados de más nivel, el entrenamiento interválico cobra mayor importancia (intensidades cercanas al VO2 max) dado que la realización de esfuerzos de mayor intensidad provocará que sean más económicos a intensidades de competición. Intensidades de entrenamiento muy altas no conllevarán mejoras en la economía de carrera debido a que no es posible acumular suficiente volumen de entrenamiento. Por otro lado, los esfuerzos de alta intensidad previos a la competición (intensidades superiores al umbral anaeróbico), es decir, durante el calentamiento, aumentan el coste de energía (reducción de la economía de carrera) y, por lo tanto, se recomienda una amplia fase de transición entre tales esfuerzos y la competición (entre 9-20 min), para que el rendimiento no se vea perturbado. Se recomienda un aumento en el aporte científico en relación a los efectos de esfuerzos de alta intensidad durante el calentamiento, con el fin de conocer qué intensidades son más óptimas, el terreno a utilizar (llano o pendiente), o la recuperación necesaria para mejorar el rendimiento

Interest in relation to running economy has increased such as determinant of running performance in scientific literature in trained long and middle distance runners and recreational runners. Trained runners are more efficient than untrained runners, meaning it is a "trainable" parameter. A key factor during endurance training is the intensity of corresponding effort, characterized by two endurance training methods such as interval and continuous training. In recreational runners, there is some controversy about which intensities are optimal in order to improve running economy, thus, periodized endurance training with a logical relationship between high and low-intensity training is recommended. We recommend the inclusion of 2-3 session per week of interval training, compensated with continuous training. Regarding to trained runners, interval training (at intensities close to VO2 max) will be more important because of the need to be more economical at competitive intensities. Very high training intensities would not lead improvements in running economy due to it is not posible to accumulate enough training volumen during the training period. Conversely, the high-intensity efforts prior to competition (intensities above anaerobic threshold), during a warm-up protocol, increase the energy cost (reduce the running economy) and therefore, it is recommended a long transient phase (9-20 min) before to competition so as not to disturb the subsequent performance. An increase of scientific studies regarding the effects of high-intensity efforts during a warm-up protocol is needed in order to know the optimal intensities, flat or uphill ground, or the adequate recovery to improve the subsequent performance

Effects of Continuous and Interval Training on Running Economy, Maximal Aerobic Speed and Gait Kinematics in Recreational Runners.

The purpose of this study was to evaluate the effects on running economy (RE), V[Combining Dot Above]O2max, maximal aerobic speed (MAS), and gait kinematics (step length [SL] and frequency, flight and contact time [CT]) in recreational athletes, with 2 different training methods, Interval and Continuous (CON). Eleven participants were randomly distributed in an interval training group (INT; n = 6) or CON training group (CON; n = 5). Interval training and CON performed 2 different training programs (95-110% and 70-75% of MAS, respectively), which consisted of 3 sessions per week during 6 weeks with the same external workload (%MAS × duration). An incremental test to exhaustion was performed to obtain V[Combining Dot Above]O2max, MAS, RE, and gait variables (high speed camera) before and after the training intervention. There was a significant improvement (p ≤ 0.05) in RE at 60 and 90% of MAS by the CON group; without changes in gait. The INT group significantly increased MAS and higher stride length at 80, 90, and 100% of MAS and lower CT at 100% of MAS. As expected, training adaptations are highly specific to the overload applied with CON producing improvements in RE at lower percentage of MAS whereas INT produces improvements in MAS. The significantly increased stride length and decreased CT for the INT group are an important outcome of favorable changes in running gait.