thanks for your friendly answer.
>
> After posting the discussion re anaerobic thresholds, etc.,
> I received a number of questions, primarily regarding why
> the anaerobic threshold is supposed to be "set" at 158 bpm.
> I re-checked my source and found the number 158 was based on
> a study doneby Persson, et al in 1974, which observed that
> when lactic acid levels reached a concentration of 4 mmol/L,
> (which is considered by equine exercise physiologists to be
> the "anaerobic threshold"), the heart rate was consistently
> between 150-160 bpm.
Would be interesting to know the details of the FUNCTION between
workload, pulse and lactic acid level. Why exactly 4 mmol/L, what happens
there ? What happens with the lactat level i.g. when heart rate rises ?
Does it goes up slowly or jumping when the "threshold" is reached ?
If it's jumping, there is a 'hard' threshold, based on physics we
ar'nt able to change and therefore it should be very important to know
about it when training the endurance horse.
When it goes up slowly, there is no 'hard' threshold, and probably
depending on the horse (and training), when the anaerobic zone is
reached.
Because the rider is typically unable to measure the lactat level during
the ride, a usefull clue seems to be RESIRATION of the horse during the
run and after break off the workout, isn't it? When respiration is low,
and heart rate returns to normal quickly, there could be no oxygen
deficit, therefore NO anaerobic work (even when the heart rate was 180
recently), or am I wrong ?
When the horse is fast and heavily breathing and heart rate stays long
time over 100 after stop workout, this appears like oxygen deficit
and the horse had worked within the ANAEROBIC zone, even when the
heartrate was not exceeding 160 while running.
Just a practical approach...
I agree to Bob Morris, that the way of keeping (maybe even more than
training?) a horse is very important where their limits are (not only
anaerobic threshold).
I firmly believe it's VERY depending on the horse.
thanks
Frank Mechelhoff, Frankfurt/M. (Germany)
& the 'taunus mountain ponies'
Ligeira (Fjord Arab mare, 11 yrs.)
Natascha (Russian mare, 3 yrs.)
Alex (Islandic gelding, 22 yrs.)