Samuel Wanjiru New World Record Holder

[Master Po]

Just checked weather.com hourly forecast for Sunday a.m.:
7:00am 33 degrees
9:00am 38 degrees
light winds 7-8mph nnw

I agree w malmo -- that's a bit colder than what would be ideal, and thus might likely affect the pursuit of ideal times. Wanjiru I'm sure will do really well, but I would guess this cold will affect WR pursuits. (I'm also wrong about lots of stuff...)

As absurd as it is, I'll compare myself to Wanjiru for a moment...at my best I was, let's say, a little bit slower at the marathon than Wanjiru (unless I count my cycling times for comparable distances, in which case I match up with Sammy really well), but nevertheless, I did have the experience of running marathons in a wide range of conditions, including some marathons when temps were in the low-mid 30s. I always liked the temps to be kind of colder than most of my training partners, but I found those cold conditions to be limiting. I did ok in those very cold races, relative to my capacities at the time, but always came away from those races thinking I could have done better had the temperatures even been in the 40s. At those temps -- just above freezing, after a while, it just starts to feel cold, especially if one has to run into even a very slight headwind (that one wouldn't even notice in slightly warmer conditions) in the later miles.

[SQUACKEE]

They have these things called ..clothes, and not just any clothes but virtually weightless and quite warm special running clothes. If we can go to the moon we can keep Sammy warm. Heat is the enemy in a marathon. Geb said he wilted when the sun came out in his last world record attempt.

Having said all that the perfect temp for a 26er is around 55 degrees,your mileage may vary.

[Conor Dary]

The forecast for tomorrow is indeed in the low 30's., but in the Loop it will feel a bit warmer. I think the weather will be fine.

[SQUACKEE]

I remember a quote from a famous runner who said his best races where when his toes were numb on the starting line.

[26mi235]

It might be a tad bit warmer in the downtown area; I think that the official station is out at O'Hare. However, if the wind comes straight off the lake it will be a bit warmer -- that water feels cold in the winter but it is definitely warmer than the air temperature.

[Gebfan2]

Here is a link to weather forcast for Chicago tomorrow: http://www.wunderground.com/cgi-bin/fin ... day=Sunday

32 Degrees, 74% humidity, and 6 mph NW wind at 7AM; 40 degrees, 57% humidity, and 6 mph NW wind at 10.

Seveveral emails above raise an interesting question that probably has an semi-empirical answer: What is the ideal temperature for running the fastest possible time for a marathon?

One way would be to look at the temperature, humidity, altitude, and wind speed for all world records, or for the fastest 100 times in history.

Another way would be to compare the average time for a field over the same course over a decade or two.

My hunch is that the ideal temperature for an elite runner will be different than an average runner (likely cooler for the elite runner). My second hunch is that the ideal temperature for a WR in the marathon is likely between 40-45F. My third hunch is that the ideal temp will likely also vary considerably between individuals, and between different humidity levels...

Unfortunately I don't have the time (or the inclination) to begin to test my hypothesis against the data today or anytime soon.

But all in all, the temp and wind looks pretty good for Chicago tomorrow compared to other years where that course has yeilded fast times and world records.

I think the fastest times for Chicago have been run at temps between 38-45 degrees, so I think tomorrow will be slightly cooler than ideal.

Go Sammy!

[Conor Dary]

Whatever the temperature tomorrow it sure will be better than 2 years ago. At 6am when I took the train in to go watch it was already in the 70's.

[unclezadok]

I'd say the ideal is 45 to 55 but then again I don't like cold weather.

[DecFan]

Unfortunately I don't have the time (or the inclination) to begin to test my hypothesis against the data today or anytime soon.

Joel did this some time ago. See this thread.

[DrJay]

Crank up the heat in all the downtown buildings and open the windows!

[malmo]

I did ok in those very cold races, relative to my capacities at the time, but always came away from those races thinking I could have done better had the temperatures even been in the 40s. At those temps -- just above freezing, after a while, it just starts to feel cold, especially if one has to run into even a very slight headwind (that one wouldn't even notice in slightly warmer conditions) in the later miles.

Master Po is on the mark. While fast times have been run in weather as cold as it will be tomorrow, it's not ideal. After the hay is in the barn, marathoning becomes an fuel efficiency/heat dissipation problem. Any world class distance runner can run at WR marathon pace for a long time without struggling the least bit. The fuel efficiency and heat dissipation variables assert themselves after 25k.

You don't have to be a marathoner to understand the effects of cold on the muscles. Everyone here has had some sort of experience training for track events. Cold slows you down. Your muscles do not operate efficiently in the cold. You simply cannot run as fast or jump as far/high or throw shit very far when you're cold. However, marathoning there is a trade-off that tilts in favor of 'cooler' weather. (notice I didn't say "cold"). One doesn't need to perform at top speed in the marathon, even at WR pace, just hard enough that you wouldn't want to carry on a conversation. "Cooler' weather mitigates the heat dissipation variable.

One of the things about looking at historical temperatures of races is that all temperatures aren't the same. Khannouchi's 2:05:42 was run in identical conditions (32-40) as what is expected to be tomorrow, however, if my memory is correct, a later start time (tomorrow they start at 7am). If the altitude of the Sun is higher that 32-40 will actually be warmer on the ground, making the real ambient temperature ideal.

If it's overcast and 32-40, it will be too cold, and there will be a lot of frozen penises at the finishline.

As far as Wanjiru goes, his fitness level hasn't been revealed so far this year.

[Gebfan2]

Joel did this some time ago. See this thread.[/quote]

Thanks Decfan.

Joel summarized the ranges for the 11 fastest marathons:

Start time ranges:
Temp: 37.4F - 55.4F
Dew Point: 18.0F - 48.2F
Humidity: 30% - 100%
Wind Speed: 0 - 10.4mph

End time ranges:
Temp: 41.0F - 62.6F
Dew Point: 21.9F - 50.0F
Humidity: 47% - 87%
Wind Speed: 2.3mph - 15.0mph

The median starting temperature for these 11 fastest races was 44.6 degrees and the mean starting temp was 45.56F. The median finishing temp was 50.0F and the mean finiishing temp was 51.14F.

malmo's right on as usual on technical/biomechanical/physiological points about distance running. Thanks. Tomorrow is supposed to be sunny in Chicago, so that will help greatly with the slightly too-cold temps...

[2 cents]

Excellent points, malmo. There is a gradually decreasing ideal temperature as the distance increases, up to a point. The marathon is indeed a textbook case of energy utilization, and any energy squandered to keep the body warm is having a deleterious impact on energy conservation, by definition, as is the energy utilized to keep the body cool. Obviously, you cannot bounce a basketball as high in 30 degree weather, and you cannot run a mile as fast either, as malmo suggests. Of course, there is a certain temperature where you have an ideal combination of enough warmth to facilitate muscle elasticity but not too much to unduly tax cooling mechanisms. And it would be a no-brainer that if you had to choose, you'd take 40 degrees over 80 degrees. But of course, you wouldn't for a mile. The study linked below, for what it's worth, suggests 41 degrees is the ideal temperature for a marathon. I think that is a little low, but not substantially so. Note also that the study suggests that higher temperatures have a smaller impact on faster runners, which again is precisely expected, much as any environmental adversity would, due to increased efficiency and fitness. From my observation, many runners overdress for racing purposes when the temperature is say, 40 degrees.
http://www.poweringmuscles.com/Sports-S ... mance.html

[malmo]

malmo's right on as usual on technical/biomechanical/physiological points about distance running. Thanks. Tomorrow is supposed to be sunny in Chicago, so that will help greatly with the slightly too-cold temps...

Not so fast, the starttime is 7am. Not much of a help. But had the temps been 50 or 60, the 7am start would have helped qreatly.

[malmo]

. But of course, you wouldn't for a mile. The study linked below, for what it's worth, suggests 41 degrees is the ideal temperature for a marathon. I think that is a little low, but not substantially so. Note also that the study suggests that higher temperatures have a smaller impact on faster runners, which again is precisely expected, much as any environmental adversity would, due to increased efficiency and fitness. From my observation, many runners overdress for racing purposes when the temperature is say, 40 degrees.
http://www.poweringmuscles.com/Sports-S ... mance.html

I didn't see any study, not even a formal abstract.

Regardless, most of the 'studies' I've seen about running, especially marathoning, don't pass the giggle test when it comes to scientific methodology.