CIM downhills

They're gentle.

Not like Boston at all. Little, punchy hills...and mainly only in the first half. It rolls a bit like a mini rollercoaster and you might have some splits a little slower and faster (think like only plus or minus 10 sec per mile). But it's like little 50' hills.

Boston is pretty much a constant downhill first 5km and then some rollers in the middle and then some legit "long hills" in Newton (mostly between 0.3 and half a mile long).

On paper (given equal weather conditions) CIM should be a way faster course than Boston.

But CIM "hilly enough" that if you don't at least train for some hills you could blow your quads out (especially if you go out way too fast in the first half...which is easy to do).

If you have legs in the last 10km at CIM you can really fly! It smooth out to a gradual downhill in the seance half. Probably the fastest (legal OTQ) qualifying course in the country. Grandmas is pretty fast too, but the weather there is more iffy.

Sage, thank you for this insightful and extremely helpful post. I ran Boston last year and told myself if I ever do it again, I need to do specific hard downhill training. But I’m glad to hear that the CIM downhills are gentle, and what you wrote about the little rollercoaster hills and the +/- 10-sec variability of mile splits is extremely helpful. So thank you.

Chicago's course is faster but the weather is way more variable. What makes CIM fast is, sure, a solidly-fast course but, more importantly, perfect weather 4 out of 5 years and fast fields.

I didn't notice the hills at all at CIM, but then again I train on rolling trails so even a short flat run has 400 feet of climbing and the average week is a few thousand feet. Maybe to flat road people there's hills, but in general people seem to get overly worked up about this.

To be fair I ran both Boston and CIM in 2015. I ran 2:19:12 at Boston on a crappy weather (slight headwind day) and then only 2:19:52 (granted I was 12th place I think) at CIM on a "so-so" weather day. On paper CIM is still a faster course than Boston:

I had a great race at Boston. I had a bad race at CIM. There might have been a slight headwind that day but I was more overcooked in training and I also went out a little too fast (1:07:50ish I think at CIM). So those relative times in my "n=1" story aren't representative of the courses. CIM would be easier to negative or more even split. Boston you're looking at a tougher even split and more common would be to "bank" 1-2min in the first half and then lose like 2-min in the Newton Hills and maybe another minute in the last 8km. At CIM the last 5-6 miles you could really fly on and basically the whole second half is pretty gentle and flattish. It's the first half of the race you have to deal with some uneven splits and extra little hill work....so kinda more opposite of Boston actually.

Compared to Chicago (basically perfectly flat) Boston is for sure slower. However, CIM (like Boston is a decent net downhill.....but more importantly it is point-to-point (which is why they aren't IAAF certified). So if you have any sort of tailwind it becomes and super fast course! Same goes with Grandmas. The thing is: Boston, Grandmas and even Houston and Chicago can get hot weather days. CIM could too of course, but generally it is cool and more stable weather in Dec in Sacramento, CA area relative to those other times and places.

I agree with everything you said about the course, Sage, but have one (possibly pedantic, but I think meaningful) correction: CIM *is* World Athletics certified (it is measured by a World Athletics “A”-level measurer, Doug Thurston, and it’s course holds a World Athletics certificate). It isn’t record-eligible and marks posted on the course aren’t eligible to be used for qualifying *times*, but performances at CIM (after receiving an adjustment for the course’s net downhill) do count toward an athlete’s world ranking (and for US athletes, with it serving as the national championship there are some nice world rankings point bonuses available). And (although this isn’t a correction, but rather a further explanation) USATF has, of course, made the decision to allow *times* run in sanctioned races on certified courses with a net downhill just greater than Boston’s to count for Olympic Trials qualifying purposes (a decision it makes independently from World Athletics), so times at CIM do (famously!) count for OTQs.

Again, all of the above may seem pedantic, but I think it’s important that fans understand how the somewhat intricate qualifying and rankings processes work (and CIM obviously plays an important role in that for US runners), and slight mis-use of terms can contribute to large misunderstandings of that.

^^^

World Athletics deducts performance result points based on the downhill. The amount of points it deducts from CIM is worth about 1.5 minutes. So a 2:09:30 at CIM would be the same amount of points as a 2:11:00 on a net zero course. The bummer is that world athletics doesn't look at difficulty of a course, just the net position. So I guess CIM is actually just 1.5 minutes faster than another course that also has about 600 elevation gain throughout. It would be less of a time difference compared to a super flat marathon course that had no hills at all.

Chicago is not as fast as CIM. Aside from CIM's net downhill (with very little climbing), Chicago has something like 35 90-degree turns. Each of those costs several seconds.

It's most important to consistently practice running the downhills fast before races, especially when preparing for races with hills. My downhill practices helped me to fly away from competitors on downhills in races, and they also gave me extra strength on the flats.

Thanks the fact check! I should've just said "world record eligible "....I didn't know about the IAAF point cert. I obviously knew it was OTQ eligible...

But I was also under the impression that it's not due to the net downhill (and neither in the case of Boston or Grandmas since they are OTQ courses as well) but rather the point-to-point nature.

For example, if a course has a start line that is over 30-35% of the race distance from the finish line you're looking at a possibility of having a big tailwind influence going mostly one direction. Like when Mutai won Boston running 2:03:02 in 2011.

I could name a lot of elite runners who have run faster at Chicago than they did at CIM. Emma Bates, Sara Hall, Stephanie Bruce, Nico Montanez, Brendan Gregg, Parker Stinson. It's hard to think of elite runners who have run both courses, but these are off the top of my head who ran faster at Chicago than their CIM times. I'm sure there are many others. There are probably some who ran faster at CIM than Chicago, but it seems to be a tossup.

Boston is tough for me, as I have no hills to train except bridges. I didn’t have a big issue with the CIM hills, but I definitely noticed them. It was my first sub 3 attempt and I crushed the last 10K (for me) to run 2:53. It was many years ago, but I think I ran a 4 minute negative split. Weather was perfect.

I do think Chicago is an easier course if the weather cooperates and you train only flat surfaces. This year seemed pretty ideal. I was much slower when I ran Chicago, but I believe I would have run faster at Chicago than CIM if I had the same fitness for each race.

As Sage said, the hills are primarily gradual rollers and occur during the first half. Take them nice and easy as it's possible to get fired up and you might go a little harder without realizing it.

The last 10K is pancake flat so make sure you pace yourself accordingly and take advantage of it. The course flattens out around halfway (13.1) where there's a huge crowd to give you a shot of adrenaline. The final "hills" would be around mile 17-20 where they are a few rollers leading up to the Wall at mile 20. From there it's hammer time...have a great run!!!

Although CIM is point to point and therefore not eligible for world record purposes due to the possibility of a tail wind, be aware that you are not going to get a tail wind. I have run it 13 times (I think), twice going 2:27, and there has never been a tail wind. However, in the 1 in 5 chance you hit a bad weather day that bad weather can include a brutal head wind.

There aren't any hills. There are rollers.

A+ write up here.

I think most people who do CIM for the first time usually say they didn't expect the uphills in the first half. It's definitely faster than Boston. Just be ready for that front half. 20 to the finish is a gradual/runnable downhill. If weather isn't an issue it's the perfect marathon finish. Boston you have the last big climb to get to 21 miles, then a monster downhill from 21-22. Then a gradual downhill to the finish. At CIM you're able to roll in that last 10k if you have the legs for it.

CIM rolls and rolls and rolls in the first half. it's just a constant up/down with short punchy hills. The uphills and downhills are longer in the Newton Hills. Mostly you have to get used to switching gears a lot because if you are the sort of runner that needs long flat patches to get into a rhythm, you aren't going to get it until later in the race.

I ran a PR on a course with over 1000 feet of elevation gain. Doesn't mean the course is faster than Berlin, where I was almost 5 minutes slower.

There's also a confounding variable when you look at elites: Chicago is a higher-tier race. Elites tend to run CIM before they've truly established themselves. Once you're good enough to get an appearance fee at a WMM, you're not likely to go back to C-level races just to chase times. I don't mean to knock CIM; it's a great race, and probably the deepest in the world at 100th, 200th, and 300th place. It's just not a race with the budget to draw truly world class athletes.