Fitness

OK, I run the same run @ 5:30AM (after being up for 45mins) and my avg. heart rate is 133.  I can't even get my heart up to 140 bpm. It's annoying.

But on the same run in the afternoon (like 4PM) I run the same run and my heart rate is 140 to 145.  I run normally at 143 to 149

I am only about 1 or 2 mins faster in the afternoon and the run is about 45 to 48 minutes long on a trail through a forest.

Is it just that you are warming up in the AM?

Thanks.

I think that it just means you are an afternoon person.  I don't think you will find that this is universally true.  Do you drink more caffeine before an afternoon run than you do before a morning run?

Hi,

I drink coffee usually in the morning like @ 8AM or so.  If it is really early I have only had some water and no food.

What kind of stinks is all the races are in the AM and that is not my best... 

When I had to run @ 8AM for 15 miles - I essentially woke up really early and ate.

Thanks.

Three things probably affecting your heart rate:
1) It's hotter in the afternoon and because of this, your heart rate  will be higher given the same effort level at a lower temperature.
2) You're running faster in the afternoon and this will raise your heart rate a little bit.
3) And what you said about your body being warmed up - here is an article for you: http://www.acefitness.org/fitfacts/fitfacts_d isplay.aspx?itemid=53

Other possible things affecting this:
Hydration level
Caffeine
Meds you may take (my inhaler raises my HR)

My initial thought was temperature, since it's hotter in the afternoon, your body has to work harder to not overheat. This is done my pumping blood to the surface of the skin to lose more heat. When it's hot outside, you have to pump more blood to lose the same amount of heat, so your heart has to beat faster.

You might try eating some carbs before your early morning run even if it's just a banana.  That should give you an energy boost.  It could just be that you don't have enough "fuel in the tank" to get yourself going.

I don't think it's the heat but it could be some of the other factors mentioned; hydration, caffeine, etc.

Hey, buddy, I almost posted a similar thread! But one major difference: my heart rate can be higher in the morning! I feel like I have to work harder in the afternoon, too, just to get the HR to a reasonable level. I have not had a chance to factor in weather although if it is hot, I definitely get a higher HR with less effort (perceived effort).

I've had to forego my trail runs for a while b/c of bad weather (ie, lightening storms), mosquitoes, and a bum muscle I'm trying to work on. Boy, do I miss it! I'm going to have to go to the track at the gym today and I am NOT looking forward to it!