Page 3 - 38Vibration_Therapy_for_Health_Promotion

Vibration Therapy for Health Promotion
DOI: http://dx.doi.org/10.5772/intechopen.105024

Figure 1.
Different waveforms related to mechanical vibration.

not fully perceived by the person, but when a movement is performed, mechanical
vibration is added to the body. However, in some activities like walking or running,
when the foot contacts the floor, mechanical vibration is more easily perceived. It
may be relevant to consider that this addition of mechanical vibration would be the
trigger for organic functions to take place and for the person to live with physical
and mental health [12, 16].
When, for several reasons, the person cannot add mechanical vibration to the
body, the mechanical vibration generated by a device can be transmitted to the
person in contact with it. This procedure corresponds to a clinical intervention
called vibration therapy [10–12].

2.3 Biomechanical characteristics of mechanical vibration

Vibration therapy, which is considered in this chapter, uses mechanical vibra-
tion, which is a physical agent that transports energy and is characterized by a
displacement in relation to an equilibrium position with an oscillatory, sinusoidal,
and deterministic movement, as shown in Figure 2.
In this case, biomechanical parameters such as frequency, amplitude, and peak-
to-peak displacement can be conveniently adjusted depending on the outcome to
be achieved and the individual’s clinical conditions. These parameters need to be
considered when designing a vibration therapy intervention protocol [8].
Frequency (f) is expressed in Hertz (Hz) and represents the number of cycles
in one unit of time, for example, the second. Peak-to-peak displacement (D) is
the measure of the perpendicular extension between the largest and smallest
displacement of mechanical vibration expressed in millimeters (mm). The ampli-
tude represents half the peak-to-peak displacement and is also expressed in mm.
These parameters are represented in Figure 3. The path of the mechanical stimu-
lus between the successive points Z1 and Z2, defines the cycle developed by the
vibration. The number of cycles performed in the unit of time is the frequency [8,
11, 12]. An important observation is that at Z2, the stimulus begins again to have
the same characteristics as point Z1.
The distance comprised by the straight-line segment between points Z1 and
Z2, measured, for example, in mm, is defined as the wavelength of the mechanical

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