Totally exhausted at much lower than usual heart rate

blackcloud13 Posts: 654 Member
A quick question for the runners (and perhaps triathletes?) out there.

I've noticed that over the past two weeks, I've felt really exhausted towards the end of my runs. That's not so unusual in itself - but I wear an HRM and it indicates about 140 while I'm dying.

Normally, I run steady at about 155 and on good days can maintain 160 for a few miles. Exhaustion normal kicks in from about 167 upwards.

So I'm baffled as to why I've struggled lately at 140, (second half of 6 mile run; 5k run section of my triathlon on Sunday)

Any thoughts / ideas? My current thinking/options are

1. Man up! You're being lazy - train harder!
2. Take a week off - you're just a bit tired
3. It's because you've had a mild cold - all exercise is affected - it's just more pronounce in a run.

Any thoughts, ideas, advice?

In case it helps - some stats. I'm 52, 80kg, 185cm, resting heart rate 70 (in summer!), typical steady state running HR 150/155, typical stressed max 167/172

One last fact - I'm a terrible swimmer and u had a really bad swim leg Sunday; could that have been a factor? (the cycling went really well, though)


  • scott091501
    scott091501 Posts: 1,260 Member
    Normally with a cold (and I assume cold medicine) you get a higher HR than normal, not lower. Not being able to get your HR up and sessions being more difficult than usual has rest week/over training written all over it to me.
  • Drudoo
    Drudoo Posts: 275 Member
    I would also agree that the perceived higher level of exhaustion is a sign of needed rest. Take a few days "off." One or two completely off, and a couple more of light swimming and walking. Then build back into your hard sessions and see what happens.
  • blackcloud13
    blackcloud13 Posts: 654 Member
    Thanks guys! I am taking this week off everything; lets hope it works!
  • davert123
    davert123 Posts: 1,568 Member
    Have a read about periodization training :)
  • Capt_Apollo
    Capt_Apollo Posts: 9,026 Member
    it could be a number of things you've mentioned. you could need a rest week or two to allow yourself a break in training, especially if you have been going strong for a long time.

    you could try spending a few weeks training 80% of the time for your swim. that'll pretty much force you to swim a lot and get better at it. the great thing about swimming is that it's not too taxing on the body, so you can swim 6 times a week without straining yourself.

    and if you've just gotten over a cold, well, you are most likely not as over it as you thought!
  • kchang77
    kchang77 Posts: 76 Member
    It could be that you are tired, but it sounds like dehydration.
  • EnduranceGirl2
    EnduranceGirl2 Posts: 144 Member
    Be careful about blaming not feeling well on dehydration (see "Waterlogged" by Tim Noakes). Hopefully you're more energetic after a rest week.