Enhancing high-intensity actions during a basketball game after a strength training program with random recovery times between sets

To examine the effects of a strength training program with random recovery times between sets in consideration of several physical parameters, high-intensity actions (HIA), and spatial exploration index during a simulated basketball game. Twenty male basketball players (age: 19.45 ± 4.36 years) were assigned randomly, either to strength training group (n = 10), or a control group (n = 10). The strength training included: parallel back squat and bench press exercises, twice a week for the duration of 10 weeks, with two blocks of 5 sets × 5 repetitions interspersed with variable passive recovery (range = 15–35 sec.) between sets, and constant passive recovery (3-min) between blocks with the load that maximized propulsive power output. The pre- and post-test assessments included jumping (bilateral and unilateral), change-of-direction, straight sprinting, and a 5-on-5 full-court situation. The external training load was assessed using the local positioning system, and the internal load was recorded with the use of individual heart rate monitors. A significant interaction effect (group x time) was observed on countermovement jump (CMJ), unilateral right hops, high-intensity accelerations and decelerations, and peak accelerations and decelerations in the 5-on-5 full-court situation. Relative improvements observed and recorded in the training group on unilateral right hops, accelerations, and decelerations were correlated. Similar results were observed on 0–25m sprints, high-intensity decelerations, peak accelerations, and decelerations. Strength training paired with random recovery times enhanced physical and game-related aspects in the observed basketball players

The Influence of Functional Flywheel Resistance Training on Movement Variability and Movement Velocity in Elite Rugby Players

The aim of this study was to identify the changes in movement variability and movement velocity during a six-week training period using a resistance horizontal forward-backward task without (NOBALL) or with (BALL) the constraint of catching and throwing a rugby ball in the forward phase. Eleven elite male rugby union players (mean ± SD: age 25.5 ± 2.0 years, height 1.83 ± 0.06 m, body mass 95 ± 18 kg, rugby practice 14 ± 3 years) performed eight repetitions of NOBALL and BALL conditions once a week in a rotational flywheel device. Velocity was recorded by an attached rotary encoder while acceleration data were used to calculate sample entropy (SampEn), multiscale entropy, and the complexity index. SampEn showed no significant decrease for NOBALL (ES = -0.64 ± 1.02) and significant decrease for BALL (ES = -1.71 ± 1.16; p p

Electromyographic response during whole-body vibrations of different frequencies with progressive external loads

The purpose of this study was to analyze if exposure to whole-body vibrations (WBV) of different frequencies with none or additional loads from 20 to 50 kg promotes changes in EMGrms activity of the quadriceps and gastrocnemious muscles. Sixteen male subjects with previous experience in strength training volunteered to participate. Subjects received the treatment while standing on a vibration platform with knees bent at 100º. Normalised EMGrms was recorded in vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF) and gastrocnemious medialis (GM) for 10 secs in the following twenty five conditions: no-vibration (NV), 30, 35, 40 and 50 Hz with body weight or with four different external loads (20, 30, 40 and 50 kg) over the shoulders. In all conditions, average normalised EMGrms from VM was significantly higher than in the NV condition. The same behaviour was observed in VL except in the 50 Hz with 20 kg condition. In RF only six conditions with 40 and 50 Hz were not significantly different compared with the NV condition. However, GM presented a different behaviour and only seven out of twenty four conditions were significantly different compared with the NV condition. The highest EMGrms was found at 30 Hz but no significant differences were found between the different frequencies employed. In all muscles except from GM and in all conditions with or without vibrations, a significant linear relationship was found between external load increments and EMGrms (%) signal increments These results suggest the use of EMGrms to monitor the optimal vibration frequency

Apunts. Educació física i esports

Resumen tomado de la publicaciónLa influencia del stiffness del Complejo Músculo Tendinoso sobre el Ciclo Estiramiento Acortamiento sugiere comparar la Actividad Electromiográfica del Press Banca horizontal Armónico con la realización del Press de Banca horizontal Oscilatorio, ambos a altas velocidades de ejecución y con diferentes cargas. Diecisiete sujetos varones, todos ellos experimentados, aceptaron participar en este estudio. Los resultados muestran diferencias en el tiempo de realización de una repetición y desplazamiento de la barra entre Press De Banca Armónico y Press De Banca Oscilatorio en la mayor parte de registros. Asimismo, el Press De Banca Oscilatorio presenta menor actividad electromiográfica aunque no se encuentran diferencias significativas para cada solicitación de carga ni entre ellas. En el total de los registros se aprecian diferencias significativas entre las solicitaciones de la Porción Clavicular y Porción Esternal en el Press De Banca Armónico en el total de una repetición y al comparar las dos fases de cada movimiento (concéntrica y excéntrica). Sin embargo, en el Press De Banca Oscilatorio se encuentran diferencias significativas entre las solicitaciones de la fase excéntrica y concéntrica de la PC y PE, pero no en el total de una repetición. Los valores de desplazamiento, tiempo y EMG demuestran que el press de banca armónico y press de banca oscilatorio son ejercicios que parecen requerir una diferente solicitación de las estructuras del complejo músculo tendinoso con un posible mayor compromiso en el press de banca oscilatorio del tejido no contráctil.CataluñaUniversidad Pública de Navarra. Biblioteca; Campus de Arrosadía; 31006 Pamplona; Tel. +34948169060; Fax +34948169069; [email protected]

Effects of direction-specific training interventions on physical performance and inter-limb asymmetries

This study analyzed the effects of two different training programs on functional performance and inter-limb asymmetries in basketball players. Twenty-four elite youth basketball players were randomly assigned to a training program including variable unilateral horizontal movements (VUH, n = 12) or unilateral lateral movements (VUL, n = 12). Eccentric-overload training (EOT) was performed twice a week for a six-week period. Functional performance assessment included a countermovement jump test, unilateral multidirectional jumping tests (i.e., lateral, horizontal, and vertical), a rebound jump test, a limb symmetry index, a 25 m linear sprint test, and several change of direction (COD) tests. Within-group analysis showed substantial improvements in almost all functional tests in both groups (ES = 0.35−0.89). Furthermore, almost all jumping asymmetries were improved in both groups (ES = 0.38−0.69) except for vertical jumping asymmetry in VUL (ES = −0.04). Between-group analyses showed a substantial and possibly better performance in vertical jumping asymmetry and 5 m in VUH compared to that of VUL, respectively. In contrast, lateral jumping with left (ES = 1.22) and right leg (ES = 0.49) were substantially greater in VUL than in VUH. Specific force-vector training programs induced substantial improvements in both functional performance tests and inter-limb asymmetries, although greater improvements of lateral and horizontal variables may depend on the specific force vector targeted

Optimal sampling frequency in recording of resistance training exercises

The purpose of this study was to analyse the raw lifting speed collected during four different resistance training exercises to assess the optimal sampling frequency. Eight physically active participants performed sets of Squat Jumps, Countermovement Jumps, Squats and Bench Presses at a maximal lifting speed. A linear encoder was used to measure the instantaneous speed at a 200 Hz sampling rate. Subsequently, the power spectrum of the signal was computed by evaluating its Discrete Fourier Transform. The sampling frequency needed to reconstruct the signals with an error of less than 0.1% was f99.9 = 11.615 ± 2.680 Hz for the exercise exhibiting the largest bandwidth, with the absolute highest individual value being 17.467 Hz. There was no difference between sets in any of the exercises. Using the closest integer sampling frequency value (25 Hz) yielded a reconstruction of the signal up to 99.975 ± 0.025% of its total in the worst case. In conclusion, a sampling rate of 25 Hz or above is more than adequate to record raw speed data and compute power during resistance training exercises, even under the most extreme circumstances during explosive exercises. Higher sampling frequencies provide no increase in the recording precision and may instead have adverse effects on the overall data quality