Recent studies have shown the importance of individualizing the vibration intervention in order to produce greater effects on the neuromuscular system in less time. The purpose of this study was to assess theindividualoptimalvibration frequency (O.V.F.)corresponding to the highestmuscle activation (RMSmax) duringvibrationat differentfrequencies, comparing different protocols. Twenty-nine university students underwent 3 Continuous (C) and 2 Random (R) different vibrating protocols, maintaining a squat position on a vibration platform. The C protocol lasted 50 seconds and involved the succession of ascending frequencies from 20 to 55 Hz, every 5 seconds. The same protocol was performed twice, having the knee angle at 120° (C) and 90° (C90), in order to assess the effect of joint angle, and after a fatiguing squatting exercise (CF) to evaluate the influence of fatigue on O.V.F. assessment. In therandomprotocols vibration time was 20 seconds with a 2-minute (R2) and a 4-minute (R4) pauses between tested frequencies. Muscle activation and O.V.F. values did not differ significantly in the C, R2 and R4 protocols. RMSmax was higher in C90 (p< 0.001) and in CF (p = 0.04) compared to the Cprotocol. Joint angle and fatiguing exercise had no effect on optimalvibration frequency. In conclusion, the shorter C protocol produced similar myoelectrical activity in the R2 and the R4 protocols and therefore could be equally valid in identifying the O.V.F. with considerable time efficiency. Knee joint angle and fatiguing exercise had an effect on sEMG response during vibration but did not affect significantly O.V.F. identification.
Individual Optimal Frequency in Whole-Body Vibration: Effect of Protocol, Joint Angle, and Fatiguing Exercise
Carlucci F;Felici F;Haxhi J;Sacchetti M
2016-01-01
Abstract
Recent studies have shown the importance of individualizing the vibration intervention in order to produce greater effects on the neuromuscular system in less time. The purpose of this study was to assess theindividualoptimalvibration frequency (O.V.F.)corresponding to the highestmuscle activation (RMSmax) duringvibrationat differentfrequencies, comparing different protocols. Twenty-nine university students underwent 3 Continuous (C) and 2 Random (R) different vibrating protocols, maintaining a squat position on a vibration platform. The C protocol lasted 50 seconds and involved the succession of ascending frequencies from 20 to 55 Hz, every 5 seconds. The same protocol was performed twice, having the knee angle at 120° (C) and 90° (C90), in order to assess the effect of joint angle, and after a fatiguing squatting exercise (CF) to evaluate the influence of fatigue on O.V.F. assessment. In therandomprotocols vibration time was 20 seconds with a 2-minute (R2) and a 4-minute (R4) pauses between tested frequencies. Muscle activation and O.V.F. values did not differ significantly in the C, R2 and R4 protocols. RMSmax was higher in C90 (p< 0.001) and in CF (p = 0.04) compared to the Cprotocol. Joint angle and fatiguing exercise had no effect on optimalvibration frequency. In conclusion, the shorter C protocol produced similar myoelectrical activity in the R2 and the R4 protocols and therefore could be equally valid in identifying the O.V.F. with considerable time efficiency. Knee joint angle and fatiguing exercise had an effect on sEMG response during vibration but did not affect significantly O.V.F. identification.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
