This is an amateur's opinion
I joined a fitness centre in November '97 having been rather lazy for several years. During the initial assessment I was introduced to the Heart Rate Monitor. This is a chest strap that transmits heart rate signals to many exercise machines and/or a watch style display unit. Generally it seems accurate except for the first few minutes and occasionally it seems to go very high; this has happened with both the Polar and Sports Instruments transmitters but may be something to do with my odd shape.
I found that it would help my workouts as I could monitor my work rate and so avoid being too idle. As my interest grew I decided to purchase my own Heart Rate Monitor. There are many different types available but I ended up getting a Sports Instruments Circuit 5. Apart from the HR Monitor function it has a stop watch and training zone setting with recall. I think it is similar to the Polar Pacer, except it does not appear to be waterproof, but I can change the batteries myself. Time will tell if I made the right decision.
I don't have a link to Sports Instruments but here is one to polar
With the HR Monitor I got a copy of The Heart Rate Monitor Book by Sally Edwards (ISBN 0-9634633-0-6.) This is an interesting read and covers two methods of 'guesstimating' one's Maximum Heart Rate, two methods of calculating the various training Zones and the Borg scale which uses the rate of perceived effort.
|Training Zone||% of Max HR||Recommended Duration|
|Moderate||50% - 60%||1 hour +|
|Weight Management||60% - 70%||30 mins +|
|Aerobic||70% - 80%||10 - 30 mins|
|Anaerobic||80% - 90%||5 - 8 mins +|
|Red Line||90% - 100%||up to 5 mins|
There is a separate page with the formulae
There are three ways I know of getting one's Maximum Heart Rate (MHR)
Next there are at least two ways of calculating the training zones, short of a full and expensive test. Each zone has a lower and upper Training Heart Rate (THR) as in the table above.
The difference between MHR and RHR is the Heart Rate Reserve (HRR).
Using my MHR of 178 this give values of 107 bpm and 136 bpm for 60% work rate using the Max HR and Karvonen methods respectively. This is where we move from moderate to the weight management zone and there is a difference of 29 bpm.
So armed with my monitor I did a simple, continuous, test on a level tread mill progressing into the aerobic zone noting the exertion and heart rate near the end of each section -
|Walking Speed||Duration||Heart Rate||Perceived Effort|
|4 mph (6.4 kph)||7 mins||115 bpm||Easy but doing something|
|4.5 mph (7.2 kph)||8 mins||125 bpm||Not too bad|
|4.75 mph (7.6 kph)||15 mins||135 bpm||Breathing deeper, mild sweat|
|5 mph (8 kph)||12 mins||153 bpm||Breathing quite hard, definite sweat|
From the test I concluded that approximate THR for me would be say
50% = 115 bpm 60% = 130 bpm 70% = 140 bpm 80% = 155 bpmThese values are between those calculated and if you're not asleep already I tried various ways of calculating the training zones. The method must really take the RHR into account so I've modified the Karvonen method by multiplying the RHR by 0.7 and then using the Karvonen formula. For me RHR = 72, multiply by 0.7 = 50, HRR = 178 - 50 = 128 and each THR = 50 + (128 * work rate ratio)
1, You don't need a heart monitor for your training (unless you are a serious athlete) but it does give something to measure your progress and a bit more. 2, If you want to lose weight you must do at least 30 mins exercise 3 times a week. If you're getting over a serious illness (heart problems maybe) then seek advice from someone who knows more about it than me! 3, If you're just starting on an exercise program it's best to work within comfortable limits so you don't give up. Err on the low side (MHR method) and then as you get fitter try the adjusted and perhaps the Karvonen method. 4, Whatever method you use to get your training zones you should improve, no method is going to be right for everybody. 5, After a hard work out you should exercise more gently the following day. You will probably feel lazier, this is not just 'in the mind', you will possibly find that for the same exercise (say walking at 8kph) your heart rate will be higher. This will go back to normal within a day or two. If you keep working out at too high a pace (red lining) your rest heart rate will actually go up, performance will not improve. This is the result of over training. 6, Best of luck with your program.
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