Enraf Nonius Endomed 482, Руководство по эксплуатации

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Modulation Program
defines the time and sequence in which the frequency will sweep through the
Frequency modulation range. See for the available Modulation programs fig 4.1.4.12.
Surge Program
can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 8.2.5.6 for details.
4.1.3.2.4 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 fig 4.1.4.4.6 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 lasts 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 µs, is the elapsed time from the beginning to the end of the initial pulse
phase. See fig 4.1.4.4.5 for details.
Pulse Frequency,
expressed in Hz or pps (pulses per second), defines the repetition rate of the TENS
pulses. See fig 4.1.4.4.5 for details.
Burst Frequency
, expressed in Hz, defines the repetition rate of bursts of pulses. A burst consists of a
train of pulses. Each burst lasts 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.
See fig 4.1.4.4.6 for details.
4.1.3.3 Premodulated
As with Interferential currents, a medium carrier frequency is used to pass the low frequency stimulation
(beat) frequency through the skin. See fig 4.1.4.1 for the current waveform. ‘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 fig .
Surge Program
can be used to adjust repeated sequences of contraction and rest periods. See
paragraph 8.2.5.6 for details.
4.1.3.4 Russian Stimulation
This current type is an intermittent alternating current with a carrier frequency around 2500 Hz. See fig
4.1.4.2 for the current waveform. Russian Stimulation was first used by Kots, a lecturer in sports medicine