Effect of a whole-body vibration training modifying the training frequency of workouts per week in active adults.

The aim of this study was to evaluate the effects of whole-body vibration by varying the training frequency (2 or 3 sessions per week) on the development of strength, body composition, and mechanical power. Forty-one (32 men and 9 women) recreationally active subjects (21.4 ± 3.0 years old; 172.6 ± 10.9 cm; 70.9 ± 12.3 kg) took part in the study divided in 2 experimental groups (G2 = 2 sessions per week, G3 = 3 sessions per week) and a control group (CG). The frequency of vibration (50 Hz), amplitude (4 mm), time of work (60 seconds), and time of rest (60 seconds) were constant for G2 and G3 groups. Maximum isokinetic strength, body composition, and performance in vertical jumps were evaluated at the beginning and the end of the training cycle. A statistically significant increase of isokinetic strength was observed in G2 and G3 at angular velocities of 60, 180, and 270°·s. Total fat-free mass was statistically significantly increased in G2 (0.9 ± 1.0 kg) and G3 (1.5 ± 0.7 kg). In addition, statistically significant differences between G3 and CG (1.04 ± 1.7%) (p = 0.05) were found. There were no statistically significant changes in the total fat mass, fat percentage, bone mineral content, and bone mineral density in any of the groups. Both vibration training schedules produced statistically significant improvements in isokinetic strength. The vibration magnitude of the study presented an adaptation stimulus for muscle hypertrophy. The vibration training used in this study may be valid for athletes to develop both strength and hypertrophy of the lower limbs.

Effects of different amplitudes (high vs. low) of whole-body vibration training in active adults.

The aim of this study was to evaluate the effects of two different amplitudes of whole-body vibrations on the development of strength, mechanical power of the lower limb, and body composition. Thirty-eight recreationally active participants took part in the study. Participants were divided in two experimental groups (low amplitude group [GL] = 2 mm; high amplitude group [GH] = 4 mm) and a control group. The experimental groups performed an incremental vibratory training, 2 days per week during 6 weeks. The frequency of vibration (50 Hz), time of work (60 seconds), and time of rest (60 seconds) were constant for GL and GH groups. All the participants were on the platform in a static semi-squat position. Maximum isokinetic strength, body composition, and performance in vertical jumps (squat and countermovement jumps) were evaluated at the beginning and at the end of the training cycle. A significant increase of isokinetic strength was observed in GL and GH at angular velocities of 60°.s(-1), 180°.s(-1) and 270°.s(-1). Total lean mass was significantly increased in GH (0.9 ± 1.0 kg). There were no significant changes in the total fat mass in any of the groups. Significant changes were not observed in different variables (height, peak power, and rate of force development) derived from the vertical jumps for any of the groups submitted to study. The vibration training, whatever the amplitude, produced significant improvements in isokinetic strength. However, high vibration amplitude training presents better adaptations for hypertrophy than the training with low vibration amplitude. In this sense, GH would be a better training if the practitioners want to develop both strength and hypertrophy of the lower limbs.

[EFFECTS OF WHOLE-BODY VIBRATION TRAINING ON BODY COMPOSITION AND PHYSICAL FITNESS IN RECREATIONALLY ACTIVE YOUNG ADULTS]. / EFECTOS DE LAS VIBRACIONES DE CUERPO COMPLETO SOBRE LA COMPOSICIÓN CORPORAL Y LAS CAPACIDADES FÍSICAS EN ADULTOS JÓVENES FÍSICAMENTE ACTIVOS.

In the last decade, it has been suggested that whole- body vibration training (WBV) may increase neuromuscular performance and consequently affect the muscular improvement as either acute response to vibration or chronic adaptation training. Vibrating platforms generate frequencies from 5-45 Hz and vertical oscillations of 1-11 mm peak to peak, affecting more or less intensity acceleration changing by combining frequency and amplitude. Vibration training, in a session as various offers different results in regard to changes in body composition and in increasing the vertical jump, sprint, and the different manifestations of force development. These promising results await further research to establish parameters (duration, frequency and amplitude) with vibration stimulation in young active subjects. This literature review provides an update on the scientific evidence on the body vibrations in order to answer the question whether WBV, meaning the exercise by increasing the gravitational load collection, is a treatment option if the aim is to improve neuromuscular function, flexibility, balance, agility, coordination and body composition.

En la última década se ha sugerido que la práctica de ejercicio a través de las vibraciones de todo el cuerpo (WBV) puede incrementar el rendimiento neuromuscular y, consecuentemente, incidir en la mejora muscular, ya sea como respuesta aguda a la vibración o como adaptación crónica al entrenamiento. Las plataformas vibratorias generan frecuencias que van de 5 a 45 Hz y desplazamientos verticales de 1 a 11 mm de pico a pico, incidiendo en una mayor o menor aceleración modificando la intensidad al combinar frecuencia y amplitud. El entrenamiento vibratorio, tanto en una sesión como en varias, ofrece diferentes resultados en lo que se refiere a cambios en la composición corporal, así como en el incremento del salto vertical, la velocidad de carrera y las diferentes manifestaciones del rendimiento de la fuerza. Estos resultados tan prometedores aguardan futuras investigaciones que establezcan unos parámetros (duración, frecuencia y amplitud) con estímulo vibratorio en sujetos jóvenes activos. Esta revisión bibliográfica ofrece una recopilación actualizada de la evidencia científica sobre las vibraciones corporales con el fin de responder a la cuestión de si las WBV, entendidas como el ejercicio que incrementa la carga gravitacional, son una opción de tratamiento si el objetivo es mejorar la función neuromuscular, la flexibilidad, el equilibrio, la agilidad, la coordinación o la composición corporal.