Stand on The Whole Body Vibrator with an accurate accelerometer placed in the center, you’ll see this for vertical “G-force” (if you weigh around 150 pounds):
If you weigh 200 pounds, peak vibration intensity will decrease by about 0.4G’s, to top-out at 5.8 G’s. Likewise, a 250 pound person will feel a peak intensity of about 5.4 G’s.
Standing on this machine: it sounds monotone. The vibration feels “smooth” and predictable. Looking closer at this data, we see smooth top peaks and slightly jagged bottom peaks:
This smooth vibration, contrasts with “rough” vibration when we look below at a competing Linear WBV machine that’s structurally more complex (more parts & less effectively isolated):
Standing on this machine: it sounds “clanky” and pulsating, which are sound-effects of these jagged accelerations and the pronounced wavy shape as overall peak intensity varies due to periodic constructive and destructive interference between out-of-phase frequencies from various parts in this more complex (and more expensive) machine. The vibration literally feels “sharper” because of these jagged peaks.
Again, zooming in for more detail:
I haven’t seen a formal study on whether rough vibration is particularly destructive on the body, joints, cartilage, etc; or even “less effective” in causing a beneficial boost to fluid flow in the body. I suspect smoother is better, just comparing the way I feel after using different machines; but I don’t expect to ever see a study to confirm or deny this.
This sort of chart represents the “fingerprint” of a particular Whole Body Vibration machine. With some experience in WBV machines, you can get an idea of what a machine will feel like by studying charts like these.
With exploding interest in this technology, similar charts might become standard product info from manufacturers, to appeal to increasingly educated consumers.
BUT WHAT IS GOOD?
Basically, once you reach 5 to 6 G’s, more intensity will not produce different or more beneficial WBV effects, in the way that moving up from 3 to 5 G’s feels like a whole new world. What matters once you’re “in the zone” is time spent on the machine. More intensity beyond that will not significantly reduce the time needed to benefit from WBV.
WHAT THE NUMBERS MEAN
All the numbers above are for acceleration as a ratio of standard Earth gravity (“G-force”), as measured directly on the platform, while a person is standing on it; but not on any part of his or her body. This is important, because some manufacturers will under-rate the performance of their machine by measuring G’s on someone’s body.
- For example, 6 G’s measured on the platform of a WBV machine while someone is standing on it, may correspond to 3 G’s when measured on that person’s head, or 2 G’s when measured on the same person’s lower back.
- Measuring acceleration on any body-part is very unreliable. One reason is that vibration intensity will focus in, or move to, a different area depending on how the person is standing: Knees locked; knees bent? Back straight; or slouching? Head tilted forward; or backward?
- Thus, the only reliable way is to measure acceleration directly from the machine’s platform, with a person of known weight standing on it.
One last thing to clarify: There are claims online such as “our machine produces up to 20G’s” or something extreme like that. That number is the “unloaded acceleration” measured if no one is standing on it; that’s not useful information. With no weight on a WVB machine, the unloaded acceleration and/or displacement (motion amplitude) will be extreme. The honest way to present this information is to specify the peak acceleration (or “G’s”) that a person will experience, depending on their weight. That’s what I’ve tried to show here.