Having Difficulty with Zone 2 Running

by Ric
(Eureka,Il)

I am a 44yr old male triathlete. I am trying Zone 2 running for the first time and I am struggling very much. I feel like I am running too slow.

I know my max heart rate should be 176 and at 70% my heart rate should be 123 and at 75% it should be at 132 and at 80% it should be at 140.

So here is where the problem begins. I am a comfortable 8:30 min mile runner and currently running at 7:02 min mile at race pace. but I am finding it very hard to stay at Zone 2.

Every time I get a comfortable stride going I have to slow down. I am currently running at about 10:30-11:00 min miles. What am I doing wrong?

Answer by Dom:

Hi Rik,
Thanks for your question about running with your heart rate monitor in Zone 2.

There can be a few different issues here:

1. Your maximum heart rate estimate.
2. The method you are using to establish Zone 2.
3. Your base needs further development.
3. Relying solely on your heart rate monitor.

Let's walk through these in more detail:

Your maximum heart rate estimate

You are saying your maximum heart rate is 176. How have you established this? It is exactly 220 minus your age, which is only a rough estimate of maximum heart rate, your max may be quite a bit higher than that.

Not sure about the science around this, but just from anecdotal evidence of people around me, those with a longer running training history appear to generally have a higher max heart rate than the 220 - age estimate.

Also see my Maximum Heart Rate-page.

The method you are using to establish Zone 2

You are referring to heart rate percentages. It sounds (from the percentages you are using) that you are using the Karvonen method of determining your heart rate zones.

The Karvonen method uses not only maximum heart rate, but also Rest Heart Rate. I have got the feeling you are not using your rest heart rate in the calculation.

Assuming you are well trained your rest heart rate might be 55 beats per minute or so (just picking a number for illustration purposes). Using your 176 as a max and 55 as your rest heart rate delivers a Zone 2, based on the Karvonen method, of between 140 and 146 beats per minute.. That's a massive difference to the range you are targeting currently!

Your Base Needs Further Development

I am not convinced this is the issue for you. Most triathletes I know have a well-developed base due to the number of training hours they log with the swim, bike and run training.

But just in case you are newer to running and cardiovascular exercise in general.... A heartbeat is your heart pumping blood around the body. When you are a bit newer to running, or exercise in general, your heart is not much used to having to pump the blood around your body more quickly. It needs to be trained, like any muscle, to get stronger. In the first 12 months of somebody's running career, or when they come back to running after a period of not doing much, their heart rate will be higher during any exercise, even 'easy' exercise.

Relying Solely on the Heart Rate Monitor

Running with a heart rate monitor can be a good thing. Especially for tempo runs for example. Tempo runs can, especially when you are well trained, quickly turn into interval running because you feel so good and you feel like pushing yourself.

They can also help keep your easy running at an easy pace, rather than pushing into tempo pace.

Your Zone 2 running is your easy pace, the pace at which you should be able to have a conversation. You don't need a heart rate monitor for this zone necessarily. At the moment it sounds like your heart rate monitor is frustrating you.

So, in case all of the above fails in providing you with an answer.... next time you go for a run, leave the heart rate monitor at home. Go by feel.



Run at the pace at which you'd be able to still talk to someone. Test yourself during the run. If you go to fast, slow down.

By the way, don't talk too loudly to yourself in busier areas, you may get funny looks... :)

Hope this helps.

Best of luck with your running and your triathlons.

Kind regards,
Dom