OK. So you know your various heart rates (maximum, resting, and the working range). Now what?
This is where it gets interesting. Unfortunately there seems to be quite a bit of confusion and a vast range of opinions about the various training zones.
Regardless of which method you use, the thinking is pretty much the same. Multiply your HRR by the relevant factor (below) depending on the zone you wish to work in, and then add your RHR:
zone 1. recovery: less than 70%
zone 2. long slow distance (LSD): 65 – 78%
zone 3. lactate threshold: 76 – 88%
Thus, rounded to the nearest 5 bpm, I get:
zone 1. less than 140
zone 2. 135 – 150
zone 3. 150 – 165
A lower heart rate is more effective for burning body fat. That’s because you’re able to keep going for longer since your metabolism is utilising a greater percentage of these reserves rather than your stored glycogen.
It’s important to know that we can only store a limited amount of glycogen. Mostly in the liver and muscles. That’s one of the reasons for “carbohydrate loading” the day before an event like a road race.
However, exercising for extended periods of time means we will eventually deplete the glycogen. This is the proverbial “wall” many runners “hit” when doing half-marathons and marathons. A bit like a car running out of gas.
I’ve heard the figure is about 1 1/2 – 2 hours worth. But I would imagine it depends largely on your level of exertion and adaptability.
Fortunately, training can “teach” the body to:
a. access a greater percentage of body fat, and
b. store more glycogen.
You just have to make sure you’re not overdoing it.
As your heart rate increases, so too does your level of fitness.
Yes, you keep burning fat too which is nice. But towards the top end of the range your body will tap into more and more of the available glycogen making it harder to keep going.
Mind you, if you’re only working out for 30 – 60 minutes then this won’t really matter.
However, exercising in this zone also increases my appetite noticeably. I guess it’s my body telling me to replenish my glycogen.
But it can be counter-productive if your goal is to lose weight.
The third zone is used for strength and speed work.
It’s recommended that you only train at this level once you’ve established a sound fitness base over a number of months. And then only for several weeks.
Generally, it’s done in the lead up to an event in which an athlete is planning to compete.
Selecting which zone depends on many factors and will be discussed shortly.
Kim | 71.5