"I'd rather be seen on my bicycle than on a park run" - Quote from the dark side

Monday 3 September 2012

Running Effort vs. The Time Of Day


During one of Bruce Fordyce’s up Comrades Marathon wins, he was the only runner in the top 30 that ran the second half faster than the first half. In other words he was the only top 30 finisher with a negative split for the race. When asked about this Fordyce replied that he ran the whole race at the same effort and therefore the flatter second half was faster. Fordyce always ran a consistent effort and did not try to run a specific or consistent pace.

Up Comrades Profile

I often do the same and try to keep a consistent effort and not always a consistent pace. Something that I find very interesting is how different my effort feels at different times of the day.

I mostly run early in the morning between 4 AM and 6 AM. I find that my total times for runs during these hours are always a lot slower than my times over the same distances when I run that between 7 AM and 8 AM or even up to 10 AM.

For example: I have a 12.2km route I run very often. When I run that during the week between 4 AM and 6 AM at what feels like a specific effort, I run the route in 01:23 – 01:26. For the same route and what feels like the same effort a bit later in the morning I average between 01:14 – 01:20. That is a big time difference over such a short route.

I always thought that I run faster with the same effort later in the morning, but my new Polar watch has proved me wrong. The watch shows that I do in fact put in a lot more effort during the later runs although it feels the same as the early morning efforts.

The pictures below shows my effort during the last three runs on this route. The sport zones show my heart rate during the runs with red=maximum intensity, orange=high intensity and green=normal intensity. Note the total time for the runs at what felt to me like the same effort/intensity.

Early morning: started at 04:50AM

Later morning: started at 07:51AM

Later morning: started at 08:46AM

The strange thing about this is that the effort I put in for all these runs felt the same to me. What does this mean? I’m hoping to find out soon. It leaves me with some interesting questions.

Do I need to push much harder when I run earlier?

Do we have optimum times of the day where our bodies perform better than other times?

How much does this differ from person to person?

What are your experiences with this? Do you experience the same? Can you answer the above questions for me?

I hope you all have a splendid week! Mine ends with the 50km Mont-Aux-Sources Challenge on Saturday.

Happy running!


17 comments:

Kate Geisen said...

This is really interesting, and one more reason I really need to steady wearing the heart rate strap and LOOKING at the data. I do often wonder if my body is working as hard as I feel like it's working.

Char said...

So is it harder to push ourselves first thing in the morning? I've read articles before that say the optimal time to exercise during the day is the afternoon but often that's the warmest time of the day which makes it harder to exercise.

I usually go in the morning because of the temperature and convenience.

ajh said...

I feel like I do best when I first get up but I have no data to tell you. I just like that time the best.

Robin said...

That's some interesting information! Both what it says and the fact that you can track it like that. I think typically I feel better in the mornings, then daytime then night time, which is why I find the night races so much harder.

Jill said...

Sorry, you lost me at negative split. What's that? I have never experienced this! ;)

What type of Polar watch did you get? I test drove one a few months ago from the local running store and it was super sweet. And super expensive :(.

"Glip" = slip, like I made a little mistake. Maybe it's not a real word and I made it up. Hum...

Abby @ Have Dental Floss, Will Travel said...

I have the exact same experience - no matter how much of a routine I'm in, it always feels like more effort to run really early. I just chalk it up to my body needing time to warm up.

Detroit Runner(Jeff) said...

My thoughts are that I'm slower in the morning because it's dark when I run so it makes me slower out of being careful. I always run faster when it's light outside.

Average Woman Runner said...

Very interesting! I do find that I can run faster in the morning, with less effort, than the same run later in the day. I like running when it's cooler, on a completely empty stomach, and without the stress of the day weighing me down.

Lauren said...

This is very interesting. I have not noticed a difference in effort between early morning runs and later morning runs. But even without graphs to prove it, I definitely notice a huge increase in effort when I run afternoon or evening runs. On another note, I almost always run a negative split, mainly because I also keep a consistent pace and the harder part is usually at the beginning of my routes.

Karien P. said...

Very interesting! To me early mornings always feel easier - it will be interesting to keep track, like you did, and find out!

Amy said...

This is fascinating - I never really thought about it before. I do know there are certain times of day where running definitely feels easier than other times, and I know I naturally run faster when it feels easier. For me the prime time is mid-morning...worst time is late afternoon.

Liz said...

I find I struggle with speed first thing in the morning, but I put that down to running before breakfast. Early evening is a good time for me, but not as practical.

Jerry Smallwood said...

Interesting, the scientist in me would like to see those figures averaged out say, after 10 runs of each type to see how that settles down and to smooth out any inconsistency such as general welfare, illness, food intake prior to the run.
I am not totally surprised by the morning run being a bit dull as you are effectively running after not eating for a good few hours...good experiment though.

RunToTheFinish said...

huh that is interesting. I wonder if it feels easier later in the morning because you've had more fuel or time to digest? I know that here the temp actually gets less humid later so my runs will pick up in pace without my really noticing it

Giorgio said...

Nice post and interesting charts, Johann!
I don't like running in the early morning with the empty stomach. That's why I've never thought about this fascinating topic before.

Anette said...

I like this! It is really interesting. I think the fact that you run on an empty stomach between 4 and 6 AM plays a role. Keep us posted with your findings.

misszippy said...

So interesting! I have never given this any thought, other than to assume that b/c I primarily run in the morning, I am probably more at ease then. I'll be interested to see what you come up with!