Monark 839 E, Руководство пользователя

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Monark Ergomedic 839 E
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7.2.3 Bruce Protocol
Bicycle ergometers measure total oxygen con-
sumption relatively independent of body weight.
Since the subject’s body weight is supported by
the saddle, the total work performed is a function
of only the resistive force and the pedal speed. At
the same power setting, all subjects will have ap-
proximately the same oxygen consumption.
On the other hand, the treadmill measurement of
oxygen consumption includes the subject’s weight
as a component of the total work and therefore
measures oxygen consumption per kilogram of
body weight. At a given incline and speed, each
subject will have approximately the same V02
per unit of body weight.
The well known Bruce treadmill maximal oxygen
consumption protocol has been converted for use
on a bicycle ergometer, taking into account the
differences between the treadmill and the bicy-
cle devices. The ergometric workload is compu-
ted using the subjects body weight to calculate
the total V02 at each stage of work, adjusting
the power settings accordingly. The total oxygen
consumption is calculated from the V02 (ml/kg/
min) for the stage multiplied by the body weight
in kilograms. The workload is then selected from
V02 workload table in the “Protocol Operation”
section.
The protocol increases the workload every three
minutes from warm-up stage to successively more
difficult levels until the subject can no longer per-
form the test. At that time, the START/STOP
key(3) is depressed to conclude the protocol. The
protocol does end automatically if a subject is ca-
pable of completing Stage VII (79.9 ml/kg/min),
an unlikely event.
The workload of the final stage is then converted
to the equivalent V02 max and reported, both
as total consumption in l/minute and per body
weight in ml/kg/minute. If the subject has not
completed at least one minute of the protocol has
been completed at termination, a “Test Aborted”
message is displayed.
Stage Speed/mph Grade % VO2 ml/kg/min
Warm up 1.7 5 12.2
Stage I 1.7 10 17.4
Stage II 2.5 12 24.8
Stage III 3.4 14 34.4
Stage IV 4.2 16 43.8
Stage V 5.0 18 56.7
Stage VI 5.5 20 68.2
Stage VII 6.0 22 79.5
The stages of the Bruce protocol are as follows:
The protocol will terminate automatically if
Stage VII is completed. Normal termination is ac-
complished by depressing START/STOP(3) when
the subject can no longer perform the work. If
the subject has not completed at least one minute
at the final workload, the previous workload is
used. If less than one minute of the protocol has
been completed at terminal, a “Test Aborted”
message is displayed. The program automatically
selects the current or previous workload, as app-
ropriate.
Performance:
Instruct subject about the protocol and adjust •
the chest belt for reliable pulse.
Setup subject age, maximum heart rate, weight •
and sex according to the menu system.
Computer Reference