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EN109-1498751-47 IFU
•
Surge Program
can be used to adjust repeated sequences of contraction and rest periods.
Burst symmetrical
The burst biphasic symmetrical pulsed current is a variation to its non-burst counterpart, in which the
continuous train of pulses is interrupted by pulse pauses. See Figure 12 for details. A burst frequency
can be set for treating chronic pains, where the use of continuous stimulation with a low pulse
frequency would be too painful. Each burst last for 100ms and the burst rate can separately be
adjusted. With this milder TENS waveform, it is easier to exceed the motorial threshold stimulus.
Parameters:
•
Phase Duration
, expressed in microseconds (µs), is the elapsed time from the beginning to the
end of the initial pulse phase.
•
Pulse Frequency
, expressed in Hz or pps (pulses per second), defines the repetition rate of the
TENS pulses.
•
Burst Frequency
, expressed in Hz, defines the repetition rate of bursts of pulses. A burst consists
of a train of pulses. Each burst last for 100 ms and the number of pulses in a burst depends on the
selected Pulse frequency i.e. at a Pulse Frequency of 100Hz, 10 pulses are available in each burst.
Premodulated
As with Interferential currents, a medium carrier frequency is used to pass the low frequency
stimulation (beat) frequency thro
ugh the skin. ‘Premodulated’ implies that amplitude modulation
occurs in the equipment, allowing it to be applied with a single electrode pair.
The Premodulated alternating current is often used where the objective is to strengthen the muscle
and change the distribution of muscle fibers (twitch speed). The Beat frequency is used to affect the
muscle fiber distribution. The optimum carrier frequency for this purpose varies between 2000
–
4000
Hz.
At a low Beat frequency (up to about 20 Hz) the muscle becomes
‘red’, while at a higher Beat
frequency (up to about 150 Hz) the muscle becomes ‘white’. This can be used to increase the
explosive release of energy in high-jumpers, provided that is supplemented by functional exercises.
The most comfortable tetanic contractions are obtained at a Beat frequency between 40 and 80 Hz.
Muscle stimulation is normally applied with a Surge program, allowing the muscles to rest between
exercise cycles.
Parameters:
•
Carrier Frequency
, expressed in kHz, is the base frequency of the alternating current.
•
Beat Frequency
, expressed in Hz, defines the rate at which the amplitude is internally modulated.
•
Frequency Modulation
, expressed in Hz, defines a variable frequency range that is summed to
the Beat frequency i.e. when the Beat Frequency is set to 80 Hz and the Frequency modulation is
set to 40 Hz, the final frequency will vary from 80
–
120 Hz.
•
Modulation Program
defines the time and sequence in which the frequency will sweep through
the Frequency modulation range. See for the available Modulation programs.
•
Surge Program
can be used to adjust repeated sequences of contraction and rest periods.
Russian stimulation
This current type is an intermittent alternating current with a carrier frequency around 2500 Hz. See
Figure 6 for the current waveform. Russian Stimulation was first used by Kots, a lecturer in sports
medicine at the Moscow State Academy. Kots used it for muscle strengthening in prosthesiology and
in the training of Russian cosmonauts. With this technique, the electro stimulation is applied both to
individual muscles and to groups (either directly or via the nerve). In direct stimulation, a frequency of
2500 Hz was found to produce the largest contraction, while the optimum frequency in indirect
stimulation was 1000 Hz.
Содержание 1498.901
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