From: mack@oakhill.sps.mot.com (Gregg Mack ( Sun ))
Subject: Re: pulse monitors
Organization: Motorola Inc., Austin, Texas
Distribution: misc
Date: Sun, 20 Dec 1992 15:27:18 GMT

"ronald hands" <ronald.hands@canrem.com> writes:

>  Speaking of pulse monitors, could anyone comment on the PulseTrack
>model that is offered by NordicTrack as a $49 accessory?  Does it work
>reliably?  (It uses an earlobe clip.)

 I have a NordicTrack Acheiver that I received the HRM free as some
"limited time offer" they had this fall.  They said this unit normally
ran $149, and not the $49 you state.  Assuming that we are talking about
the same unit, I feel I got my money's worth (free!), but I'm only
satisfied (as opposed to happy, unsatisfied, or impressed). 

 This unit allows you to store 3 different "user profiles" into its
memory.  My wife uses one "slot", and I use the other two; a hard
workout and a moderate workout.  Each of these "user profiles" lets
you enter the age, sex, weight of the individual, as well as the leg
resistance setting that will be used for the workout.  The total time
that you normally wish to ski is also entered into this profile.

Once you start skiing, the display shows you three things simultaneously.
The top display field shows your choice of either current speed, distance
travelled, total calories burned (in this workout), or your current heart
rate.  The "total calories burned" uses the information that you entered
into your user profile and combines it with your actual speed.  This
calculation assumes that the arm resistance is set to 1/3 that of the
leg resistance.  I usually keep the leg resistance at 15 lbs and the arm
resistance at slightly less than 5 lbs.

The lower left field in the display will show your choice of one of
these three: Performance Index (PI), current calories/hour rate, or
ski stride rate.

Both the top display field and the lower left display fields let you
change the functions you wish to view either while exercising or
resting.

The lower right display field shows the timer which can either count
up or count down (from an initially set value).

Sounds neat, huh? Well, yes and no.  The PI is some arbitrary value
that I view as worthless.  Most of the other functions don't average
the input data over a very long period of time, so the values change
pretty fast and can vary pretty wildly.  For instance, I leave the
lower left display on the ski stride rate.  I think this means some-
thing roughly equivalent to what a cyclist refers to as cadence (pedal
RPM). The readout will change about every 1/2 second and will show a
sequence of numbers like: 96.5, 98.2, 98.0, 94.9, 97.3, 100.1, etc.
This may be accurate, but it is kind of annoying to me.  The speed
indicator doesn't seem to be quite so sensitive.

The heart rate monitor is OK.  It does use an earlobe clip, but also
includes a clip to attach to your shirt to act as a strain relief.
This unit takes a while to find and then lock in on your heart rate.
Normally massaging the earlobe vigorously for several seconds and then
reattaching the earlobe sensor will help it along considerably. Once
it does lock onto your heart rate, it does appear to be very accurate.
I have another unit that I use on my indoor execise bike that I clipped
onto my other earlobe at the same time that I was using the NordicTrack
unit.  The correlation was very good, as they consistently read within 
2 or 3 bpm of each other (the units would alternate between which one
would have the highest reading at any given point in time).

You ask is it worth it. Well, I'd have to say yes.  The reason is that
my perceived exersion level was way off from my actual exersion level.
Let me explain.  I am a cyclists by choice.  I know what my heart rate
is (pretty close, anyway) for a given situation on my bicycle (or
indoor exercycle).  When I use my NordicTrack and use it to where I
feel that I'm at a high perceived level of exertion, my heart rate is
way too high.  For me, a 38 year old male, a heart rate of 155-165
on my exercycle produces a damn good hour long workout that doesn't
leave me sore or fatigued afterwards.  When I use my NordicTrack to
the same level of perceived exertion, I find my heart rate is up in
the 175-185 range, and I can get tired and beat in about 25 minutes
or so.  I use the heart rate monitor on the NordicTrack to "slow me
down" by decreasing the leg and arm resistances, along with my ski
stride rate to get my heart rate down to below 160.  When I do this,
I can do my once a week endurance ride for an hour (on the NordicTrack).

This is why I say that it is worth it.  If you already have the speed-
ometer, I don't see any advantage of having the NordicTrack brand of
HRM over any other (like the chest mounted Polar models). The chest
mounted variety could also be used while cycling, walking, or jogging,
while the bulkiness of the NordicTrack model would pretty much prevent
it from being used in these activities.

-- 
Gregg Mack                  ---------- __o       __o       __o       __o
gmack@paceline.sps.mot.com  -------- _`\<,_    _`\<,_    _`\<,_    _`\<,_
Motorola RISC uProcessors   ------- (*)/ (*)  (*)/ (*)  (*)/ (*)  (*)/ (*)
Austin, Texas  USA          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Newsgroups: misc.fitness