Half Marathon Newbie Heart Rate Advice

Sorry about the long post but I'm bewildered by all the conflicting information available on heart rate training. I'm hoping that you can clear up my confusion.

I am a 49 year old recreational jogger. I've only ever run one race two years ago for the experience. A 10K that I did in 1 hour exactly. Although I 'trained' regularly for it, there was no real plan to what I did.

I have entered a half-marathon to give myself some motivation for training and this time decided to get a little more 'scientific' about it. To get a training plan that fitted with the time I had available before the race, I chose a custom plan from myasics. This focuses purely on pace based upon my 10K achievement. It categorises training sessions with words like jog, build-up, fast and comfortable to describe specific paces and describes how hard you should be breathing. I am attaining the specified paces and have been using a heart rate monitor to just check I'm not doing anything stupid.

I estimated my MHR using the formula 217-(0.85*age) = 175. My resting HR is currently 58.

The current phase of the training plan is supposed to be getting me to run faster. On my last 'fast' 5 mile session, the target pace was 10:34 - 9:55 min/mile. I averaged 10:27 and my average HR was 151 which is within my 70% - 80% of WHR. I found this quite comfortable. I have done the same distance at faster paces within 80% - 90% of my WHR but found that hard work, not enjoyable and I was very tired afterwards.

1. Given that I'm supposed to be getting faster, should I be training in the more demanding 80% - 90% zone?

The next phase of the training plan is to get running further followed by a race simulation phase that combines distance and faster pace. Finally there is a tapering off before the race.

The target race pace of this plan is 9:54 min/mile that I will build up to over the next few weeks.

2. What % of WHR should you be running the half-marathon race in? Since I'm finding it hard to sustain 80%-90% of my WHR, I don't want to attempt to go off at that pace and threaten my chances of finishing.

I'm confused because I did wear an HRM during my 10K and found my HR to be off the charts for long periods of it.

3. I've also noticed that when I do longer 'comfortable' runs of 7.5 miles, my HR tends to climb toward the end of the session even though my pace is slowing. Is this a sign that I'm running out of energy and should be scoffing some of these gel things that I read about?

Thanks a lot in advance for any advice.


  • Hi - first of all congratulations on starting and having a plan! Great start.
    If you are serious about running with a HRM, I strongly recommend a book called Heart Monitor Training for the Compleat Idiot by John L Parker Jr. It will help answer your questions very comprehensively.

    In brief although the formula you have used gives abroad indication of your Max HR everyone is different. If your HR goes above this then clearly your Max Hr is higher and therefore your Working and recovery rates will be affected.

    Running at around 65-70% WHR is a great fat burning zone and it also helps develop your blood circulation and system. This all takes time and you are better not overdoing it. It sounds strange but it works. I am training for New York Marathon and am doing a 10K on 11 Sept and 1/2 Marathon on 25 Sept. When I started out I was running around 11 mins per mile over longer distances and finding it quite tough going. I did a 10K run at the weekend and was running 8.55 min miles relatively easily. Most of my training is done at 65-70% WHR which for me is 140bpm. I do some speed work but it is limited to one or two runs a week.

    Essentially I am training my body to run faster with the same level of effort - which is vital as you tackle longer distances. Yes your HR will go up on longer runs as your body depletes its Glycogen levels - again this can be improved by running slower.

    Hope this helps - let us know how you get on
  • Hi Tim,

    Thanks very much for your reply and the book recommendation. I'll get hold of a copy and study it.

    If I understand you correctly, you advocate doing sessions to increase distance at the 65-70% level and sessions designed to get you faster at the higher rate provided you only do them once or twice a week. Is that right?

    About this glycogen depletion, can you do anything about that during a long session? Do these glucose products help to mitigate the effect or is it just a load of marketing hype?

    All the very best with your upcoming races and the New York!!


  • Hi WFB
    Yes I do longer distances very slowly at first keeping within my 65-70% rate even if this means going REALLY slowly!
    But doing this I am now more than a minute a mile faster for the same effort level than I was a couple of months ago. It is really tempting to think that training fast means you will run fast in an event.

    My first speed sessions involved doing something called Fartlek for half an hour. After a suitable warm up I run 1 minute as fast as I can then the next minute is slower than walking by way of recovery. This is then repeated 10 times then warm down.

    Important not to over do it - take recovery days too.

    I'm trying the Gel bars on runs of an hour or over taking one every 25 mins or so. Jury's out as to whether they help but my feeling is they do.

    ps We were on The Gower last weekend staying with friends!
  • OK thanks Tim. I have been doing that on the runs in my plan designed to increase my distance and, comparing my times for the same routes, I am getting faster as the weeks go by. More by luck than judgement it would appear that I'm doing something vaguely right.

    The Gower is gorgeous isn't it? Especially on a day like today with the sun out. I had a run along the hard sand on a beach in Cornwall last weekend - fabulous.
  • Hi Tim. Thanks again for the book recommendation. As you say it answers all my questions exactly.

    I don't really have a gap in my training plan to do the max heart rate stress test so I'm going to stick with the estimate formula recommended in the book for now. Interestingly it gives me quite a few more bpm to play with than the previous formula I used.

    What surprised me is that I can and should train harder than I thought I could for the fast sessions.

    Once I get through this half, I'll do a proper stress test then.
  • When you look at HR its amazing what difference 5bpm can make - particularly at the top end!

    Best of luck with the Half, which one are you doing? I'm doing Oxford on 25th September
  • That's a fact!

    Cardiff on 16th October.

    Good luck with Oxford. I used to live there. Depending on the route, it should be really scenic however there are quite a few hills to watch out for!!
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