just watched the NYC marathon TV coverage. noted that most pro women wore spandex and most pro men wore loose running shorts and tank tops.
over 26.2 miles wouldn’t the men benefit from more aero clothing? is the alternative argument for comfort or less restriction?
podium vs. non-podium had only a 12 sec difference. curious.
The likely answer is tradition.
They dont yet market compression socks in Runners World…
Because the Kenyans are so skinny that even spandex would be loose on them.
No really though. Probably comfort - have you ever run in a loose, well fitting jersey and race shorts? It’s almost as good as running naked, without the jail time.
Could it be as simple as comfort? I have spandex tights for colder running from about 15-40F when doing long runs, butr racing I’d wear shorts down to about 30F. As long as you keep your hands and head warm, you don’t need much on your arms or legs. But for arms I’d wear long socks on my arm so I could adjust how warm I was.
Women tend to wear tights about 10F higher temps than men would. And people from Florida also tend to wear more clothing than those from the north. Heck the Canadians would probably just go commando at todays temps. 
The likely answer is tradition.
+1 Talk to the pure runners about how they feel about spandex. It’s both an image thing, and runners spend virtually no time thinking about air resistance.
Great question. I’ve been thinking about trying to find some spandex running shorts to try out. I think they would be more comfortable (no liner seam/edge, less rubbing) and probably marginally faster.
A better question might be, why don’t triathletes change into running shorts for the marathon (like current Hawaii run course record holder Mark Allen did)?
Less room for sponsors.
because, imho, running shorts and a singlet are way more comfortable for running.
They dont yet market compression socks in Runners World…
Really? I thought I saw like half the field in them or calf compression sleeves today. Including yours truly. They are a great way to keep your legs warm without restricting movement!
because they don’t have to swim and bike before they get to the run. The better question is why do some triathletes wear spandex during training runs when they could have worn running shorts?
Like many people I wear whatever is comfortable on the bike. If it’s a longer bike, I wear spandex under the bike shorts (or a uni). They don’t wrinkle.
But I would think a major reason is that the guys you watch who run a 2:10 marathon, don’t have to worry about soggy wet clothes, they’re running at about 12 mph and they stay pretty dry (they also started dry).
Even the best Tri guys are running slower than 10 mph (in IM), and me, I’m lucky to make 6mph. I get off the bike as wet as when I got on, and from there I’m a plodding sodden mess, when I wore shorts they just got loaded (and low), the socks get squishy and the shirt is a floppy soup. And thats on a cool day.
For us, spandex works.
because they don’t have to swim and bike before they get to the run. The better question is why do some triathletes wear spandex during training runs when they could have worn running shorts?
Unexpected responses. I find tri shorts/spandex infinitely more comfortable than running shorts. No chafing for me in tri short, but, I have had some chafing with running shorts. Plus, I like more support for the boys than I get with the liner in running shorts.
I find tri shorts/spandex infinitely more comfortable than running shorts.
I’m with you, I do all of my running in tri shorts.
aerodynamics isn’t nearly as big an issue as it would be in a speed event like the 100 meter or something like that. if you have to wear it, it might as well feel like you are wearing nothing…less constrictive.
Unexpected responses. I find tri shorts/spandex infinitely more comfortable than running shorts. No chafing for me in tri short, but, I have had some chafing with running shorts. Plus, I like more support for the boys than I get with the liner in running shorts.
Funny, I have the exact opposite experience. I hate running in tri-shorts. Then again I was running for almost 30 years before I ever ran in tri-shorts so that probably has something to do with it.
I find spandex far less chaffing than running shorts as well.
Obviously this is a personal preference.
i think we may eventually see them experimenting with clothing more similar to sprinters. the records are getting harder to break!
The only time I did training runs in spandex was when I was first starting out running and my thighs were so fat that no amount of bodyglide could prevent the chafing. No desire to go back to those days, thank you.
I do have some traditional looking running shorts that have a hint of lycra woven into them, and that 1% lycra seems to make them significantly more comfortable than the 100% nylon shorts.