Re: Heartrate Threshold

[Susan Evans Garlinghouse <suendavid@worldnet.att.net>]

.  So I'm not so sure a horse's heart
>  wouldn't be capable of re-filling and pumping out a fresh load of blood
>  at 240 bpms---after all, it has been documented on more than one
>  occasion.
> 
>  Susan >>
> 
> My information comes from Dr. Fred Fregin and others who specialize in equine
> cardiovascular systems.
> 
> ti


Well, I dunno.  I've never seen with my own two eyes a heart rate that
high (though we VERY rarely run horses flat out on our treadmill), I did
find four different references from different authors and sources that
documented HRs up to 254 bpm in TBs.  The highest HR were in yearlings,
so it certainly wouldn't surprise me that HR that high aren't seen in
older horses on the track---personally, I think anyone running a
yearling obviously close to stroking out is really flirting with
disaster, but apparently it WAS measured without ill effect to the
horse.  Anyway, I agree anything over 220 would be pretty unusual, and
I'd still check the equipment pretty close.

BTW, Frank (I think) said something about horses having the highest
cardiac output of any animal.  Actually, I think the rorqual whales have
the record on that (I once helped dissect a beached blue whale and could
have crawled through the aorta), though if you adjusted for metabolic
body size, then I'd agree horses probably get the prize.

Seeya,

Susan