As the movement of the platform

is sinusoidal, the acceleration transmitt ed to the body is

calculated as a = A (2πf)2. Where “A” is the amplitude of

the oscillations and “f” is the frequency. Small changes in

amplitude and frequency determine relatively large changes

in acceleration and magnitude of vibration being transmitt ed

to the body  so for non athletes 30 hz is good

thank you Farshad for your answer but  what do you think about moderately active athletes maybe 30 hz can be not enough 

you can use frequency with progressive method

I think that, as showed by Di Giminiani et al. (J Sports Sci. 2009. 15; 27(2):169-177), the individualized vibration frequency, determined by monitoring EMGrms activity, produces a more beneficial response to neuromuscular system than fixed pre-selected frequency.

thank you very much

There should be no difference between Amateur an Professional athletes. It. is all about activating a certain muscle Fibre Type. Type II fibers give their optimum activating response with  a frequency of around 27. Type II fibers  have  a  twitch Time of  38 milliseconds  or around 27 contractions per second. See my study on leg muscle activity here in Research Gate.

Article Leg Muscle Activity Level and Rate of Perceived Exertion (RP...