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Tetanic contraction/muscle twitch
When a muscle fiber is innervated by a motor neuron, its mechanical response is
very brief, and always identical. It shortens and then returns to its original length.
This is what is known as a muscle twitch. Twitches occur separately at frequencies
of under 10 Hz, i.e., there is no real contraction of the muscle. At frequencies of over
10 Hz, however, the twitches act as one and cause the muscle to contract.
Pulse duration
The interval between onset of the leading edge and the end of the trailing edge
of a pulse wave, that is, the time the muscle stimulator is energized during each
cycle. Generally expressed in microseconds (us). In order to minimise the amount of
electrical energy required, the pulse duration should be the same as the excitability
coefficient (chronaxy) of the motor neuron that is responsible for innervating the
target muscle.
Pulse frequency
The number of times a pulse is repeated per second is the pulse frequency. It is
expressed in hertz (Hz). A frequency of 10 Hz means that the pulse is repeated 10
times every second and that, accordingly, the muscle fibers twitch 10 times every
second. Likewise, a frequency of 25 Hz means that the pulse is repeated 25 times
every second, and that the muscle fibers twitch 25 times every second. When so
many twitches occur in such a short space of time, however, it is not possible to
distinguish them as individual twitches. This phenomenon is known as temporal
summation. Instead of a series of individual, consecutive twitches, what occurs is
a fusion of twitches, or a true tetanic contraction (this process is also known as
tetanisation). The greater the fusion, the greater the contraction force, and the
greater the work per unit of time.
Rest time
The length of time between contractions is the rest time.
Ramp up
The time it takes for the intensity/energy level to go from 0 to the programed value
is the ramp up. The exercise programs have a ramp up time of 2 seconds at the
beginning of the contraction phase.
Ramp down
The time it takes for the intensity/energy level to go from the programed value to 0.
The ramp down is one second after the contraction phase.
Intensity
The determining factor in electrical stimulation is the magnitude of electrical
charge (microcoulombs) applied. In the case of rectangular pulses, the magnitude
of charge is calculated by multiplying the duration of the pulse by the intensity of
the current. When stimulation is performed using a known pulse duration, the
intensity (expressed in milliamperes or mA) is a reproducible indicator of the
degree of stimulation.
definition of terms
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Feature
Contour
®
EMS
Other EMS
Contour
®
Advantage
Power Signal
Voltage Regulated
Current
Regulated
Provides safer, stronger more
comfortable user experience
Electrode Size
2.75" x 5"
2" x 4"
2" x 4"
2" x 2"
larger electrodes = more muscle
fibers activated and more comfort
Backlit screen
Backlit screen stays lit
at 100% while you are
setting-up your session
NO
Easy-to-read and program in any
light conditions
diet Guide
Contour Diet Guide
contains a 1,400 and a
1,800 calorie a day plan
NO
Maximize your results by
following this balanced
eating plan
Exercise
Program
Contour includes a
12 Week Total Body
Dumbbell Program
NO
Maximize your results with this
total body exercise guide
Pulse
Frequency
1-120 Hz
50-70 Hz
Work a large variety of
muscle fibers
Pulse Duration
200 or 500 (us)
200 or 300 (us)
Larger pulse duration for more
effective muscle contractions
User
Information
• Maximum Intensity
• Average Intensity
• Total Sessions,
• Total Minutes
Some capture
last session,
others don’t track
any info.
Contour keeps a running training
journal to help you stay
motivated and track progress
last Session
Repeat your last session
Some do/ some
don’t
Skip the set-up menus -
get right to the workout
Mounting Clip
The Contour Electronic
Muscle Stimulator can
attach to belts
lanyards or armbands
NO
Secure your Contour muscle
stimulator for a hands-free workout
the contour difference
Contour electronic muscle stimulators actually mimics the brains natural
electrical signal at the muscle. This gives you better muscle activation with
a comfortable user experience. With Contour, the human body takes exactly
the amount of electrical current it needs to contract the muscles and then it
naturally increases its impedance to reduce the current. Other stimulators
force a large amount of current into the body (That creates the discomfort or
burning feeling users can experience with a current regulated devices.) Simply
put, Contour electronic muscle stimulators have more power, giving you more
comfortable contractions and producing better results.
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