From: rgw@mame.mu.OZ.AU (Richard Wraith)
Subject: RE: Heart Rate for optimum training benefit
Summary: guide to finding heart rate required for training
Keywords: heartrate, training, aerobic
Organization: Computer Science, University of Melbourne, Australia
Date: Thu, 10 Sep 1992 01:45:46 GMT



	The subject of the method for determining ones heart rate for
training benefit is a little complex.
	The old 220-(your age)=your max heart rate
	then aerobic training range = 75% of max heart rate

		is a very rough rule of thumb that works OK for
many people, but for anyone who is anything more than someone
exercising to keep fit it is often wildly inaccurate. In fact
many people have maximum heart rates around 175-180 at age 20,
trained or untrained. So the above rule would be disasterous for them.
At the same time many people have a much higher max than 200, some
up to 240 even in their 20's.
	The most accurate method of finding your max heart rate is
to do a progressive step test in the sport or exercise you engage in.
	To do this you require a heart rate monitor, preferably with 
a memory, and an exercise set up that has a work rate output. ie. a
rowing machine, treadmill, bicycle wind trainer etc. Heart rate 
monitors are becoming cheaper by the week and are available at most
good bike stores and sports stores.
	The protocol for the test is as follows:

	1)begin with a gentle 5-10 minute warm up

	2)Then go for 3 minutes at a very gentle pace
	recording heart rate about every 30 seconds

	3)stop for 30 seconds then start again for a further
	3 minutes at a slightly higher intensity.
	
	4) Continue the above cycle until you reach your absolute
	maximum performance - which should be at your maximum
	heart rate.

	5) The size of the steps varies for each sport, but for
	my sport 50 watt steps on a concept II rowing machine
	seem to work the best - up to a max of about 600 watts.

	The above will give you your max heart rate and a rough guide
to your anaerobic threshold (the point where you body's capacity
to supply oxygen is not sufficient to keep up with your work rate,
ie. lactic acid begins to build up significantly). To find the anaerobic
threshold plot the results on a graph of heart rate on the vertical 
axis and power output on the horizontal axis. The graph should be close
to a straight line for lower heart rates (the aerobic region) then it
will begin to flatten out. The point it begins to flatten out is
the work rate level at which your aerobic system ceases to be able
to supply all your power requirements and your anaerobic system kicks in.
	Your aerobic training region is close to 75 % of the max
heart rate, as I said before. This test can be done at home or 
at your gym or sporting club.

	To be more precise than this a step test must be done while
taking small blood samples after each 3 minute period. This is 
done to measure the blood lactate level. This is the most accurate 
guide as to what your body is doing with regard to aerobic vs anaerobic
metabolism. The concentration of lactic acid in the blood is a very
good guide to just what energy system your body is using. The heart
rate is a good rough guide, but still quite inaccurate. Heart rates 
are still taken during the lactate test to indicate at what Heart rate
what is happening. Then for training in the field only a heart rate monitor
need be worn to indicate the intensity of exercise. The above tests
can be done at sports science labs, some universities and some 
medical clinics.

	Proper training should incorporate many levels of training intensity
from low intensity aerobic to high intensity maximum efforts.
	80% of training should be low intensity aerobic
	5% should be at around anerobic threshold
	5% should be just below max effort
	5% should be at max effort
	the remaining time should be stretching and skills work.
		The above applies to endurance sports such as 
cycling, rowing, swimming, running etc.


	This is just a very shallow dip into the field of training
theory and practice, but I hope it helps. Maybe it will inspire some
to investigate further at a good book shop, sports organization or
local university or college.


		Regards
			Richard Wraith
		e-mail: rgw@sungear.mame.mu.oz.au

Newsgroups: misc.fitness