It has been established that training 1 limb will elicit some gain in the opposing limb. This is done primarily through changes in the central and peripheral nervous system.

Goodwill and Kidgell, 2012 performed an experiment with two groups. The first group performed unilateral leg training while the second group performed unilateral leg training and unilateral vibrational training. Over 3 weeks, the individuals trained 4 days a week following standardized protocols.

They found that the un-trained limb increased in strength 35-52% in both groups with no statistically significant difference

Again, we find that whole body vibration does not contribute to strength training in any meaningful way. People are bringing these to gyms, clinics and even using them in their homes. If you are not an astronaut who spent weeks and months weightless, they will give you little benefit. There is no easy solution- go to the gym, lift heavy.