We are a writer and a doctor captivated by the quest to break the two-hour barrier for the marathon. Ask Us Anything!

Do you think the first sub-2:00 marathoner will be someone who jumps to the marathon early in his running career (like Lesisa Desisa), or someone who spends his 20s running shorter distances on the track and then moves up to the marathon in his early 30s (like Eliud Kipchoge)?

It's such a good question. Both Haile and Eliud are evangelists for that second approach, and it seems to have done them no harm! My feeling is that the guy who breaks it though, will do it in his mid-twenties rather than his late twenties... Mike will have a view on the physiology of this, but I think if the guys got set up to run longer, earlier, I think we could see some crazy times. This kid Geoffrey Kamworor who's running on Sunday in New York is an immense talent. If he has a good day in Berlin in a couple of years' time he could break the world record.

Mike's having some technical difficulties. He'll have stuff to say about this one in particular. I often think about Derek Clayton who ran 200 miles a week in training and how he ever stayed competitive in races with that amount of work he did....

The current trend is for younger, could be due to the financial incentives and not the physiology. Historically older was better

It's all about $$$. No money in track any more (unless you're Usain Bolt).

What's the most surprising thing you discovered in the time that it took you to write your book?

Will we ever see a sub-two hour marathon in our lifetimes?

The most surprising thing for me was just how wrong everybody always is when they make athletic predictions... Sports scientists have been wrong for a century or more. We always think our own era is the ultimate, and we always improve. The sub-2 marathon appears to be impossible to a lot of physiologists right now, but I guarantee we're going to get there. Let me take a punt and say 2030. Mike may disagree...

Ed, I have been thinking about this for about 30 yrs and in that time the record has fallen 4-5 minute. Our statistical estimates say sometime in the 2030s. Could happen faster with a fast field, incentive based prize money, the right course and good cool temps.

It's all about taking it out of the cities in my opinion. A special track, the right weather conditions, financial motivations, a team of crack pacers. You could do it pretty soon in those conditions.

What was harder for you: writing a book or running a marathon?

Running a marathon was extremely hard for me. I'm a big dude. 240 pounds, 6 foot 5. But it only lasted a little more than four hours. The book's taken four years.... I'd take short sharp pain (relatively speaking) over the long and sometimes very painful process of writing a book....

Is "runners high" a real thing?

For sure it's a real thing! Geoffrey Mutai talks about a feeling he gets when he's trained well, and he's flying at the front of a world-class field. He calls it The Spirit. It's a high.

What do you think of Galen Rupp's marathon potential (if he ever runs one)? Could he be the first American-born runner to run under 2:06 (not counting Ryan Hall's massively wind-aided 2:04, obviously)?

I'm not sure Galen's going to be a great marathon runner, but you never know... It seems like the Salazar operation up in Oregon makes a lot of great track stars - incredible finishing speed, and so on - but the marathon rewards a lot of different qualities. He's got the talent, but I don't know whether he's going to be a sub-2.06 guy.

Thanks for the reply, Ed. I'm really excited to read your book. Speaking of Salazar, I find it curious that he seemingly struggles the most to develop marathoners, when he himself was a much better marathoner than track runner. Just look at Mo Farah's marathon debut compared to Bekele's, or even the success Luke Puskedra's had in the marathon since leaving the Oregon Project.

Thanks so much! It's weird isn't it about Salazar's relative lack of success in the marathon. I was quite shocked that in London, Mo Farah didn't even try to go with the leaders. He obviously knew he was not in the same class.

OK, That's all me and @drmjoyner have time for. Thank you so much for all your questions!

And thank you so much @drmjoyner for taking an hour out of your life to help me out with this...

Dr. Joyner, how prevalent do you think microdosing (and other forms of nearly impossible-to-detect doping) is among elite marathoners? And what will it take to get all countries to start mandating out-of-season testing? While I initially had high hopes for the biological passport, it seems fairly easy to manipulate ... just look at the BBC's doping documentary from this past summer, where the reporter microdosed EPO and had no problem passing the bio passport.

Mike's going to be back in a minute... His browser "hates him" he says. But I have a thought about that BBC doping doc. That guy (who I know, and is a good reporter) "beat" the bio passport for 8 weeks. The whole point about the passport is that it measures values over years, not weeks.

With that said, there is plenty of doping in the marathon as in all sports. The key is developing more and better ways of testing and actually doing the tests out of competition in a rigorous way

very prevalent, the tests are beatable and we will never get there with testing along a whole host of better systems and procedures need to be in place to close the holes in the current system. Most big 'busts' have been via traditional 'police' work and not testing per se

That's actually how anti-doping's always needed to work. A combo of police work and testing. It's just that the testing's not as good now as it could be.

Favourite character from Looney Toons?

Got to say Daffy Duck. So much spirit.

It's perhaps the greatest what-if question in running history: What times do you think Sammy Wanjiru would be running right now if he were still alive?

It's a big what-if. Sammy was boozing so hard he might just be a fat washed-up could-have-been even if he hadn't fallen off the balcony that night. But if he stayed healthy, stopped fooling around? I think he'd be the world record holder for sure, and I don't think 2.02-low is ridiculous.

What did you learn about training while reporting this book?

In short, train hard hard hard on intervals. The top guys do all their most intense work on intervals. The key to speed is shifting your pace between fast and slow. That's not new thinking (it's 80 years old or more) but the East Africans approach intervals with a kind of biblical intensity.

Also, drink as much tea as possible.

Will Chicago's decision to eliminate rabbits from its race cause other big-city marathons to follow suit? Surely Berlin would never disallow pace-setters, but London might. And if so, how much would this hurt the quest to run a sub-2:00 marathon?

They might do. I don't know whether Chicago was a better race without pacers but in general I'm all for guys just racing each other rather than the clock. There's only really one place where the record gets broken at the moment anyway - and that's Berlin. As I said, I think the real shift in the record will come if the marathon moves away from the big-city template

Times at Boston and NYC very consistent last 20-30 yrs and 2:08 will usually win. So it will have an effect.

Except for that 2.03.02!

Big tailwind as you know

Also big talent. 2.05.06 in New York six months' later. Was that tailwind?

Can anyone take down Wilson Kipsang on Sunday? Could his DNF at Worlds portend a poor race at NYC, or do you think he just dropped out due to the oppressive heat?

To be perfectly honest I don't think Wilson's heart was in the World's. He'll be ready for New York. I think there's a couple of guys who could take him down. My outside pick? Kamworor, who is due a good marathon and who I'm told is in rude shape.

What are your favorite running books (aside from yours, of course!)?

I really like Bernd Heinrich's book.... It's short, weird and very interesting.

If the elite marathoners from the 70s and early 80s (say, Frank Shorter, Steve Jones, Bill Rodgers, Salazar, et al.) had all the advantages of a top modern-day athlete (shoes, training knowledge, nutrition knowledge, etc.) how much faster (if at all) would they have been able to run in the marathon?

I don't know if they would have gone much faster, tbh. Their times are so much better than many of the current generation who do have all those benefits. I'd argue that keeping it simple, working hard, and so on will do more for you than any number of high-tech training aids. Alberto Salazar may disagree.

What they did was unpaced and as I mentioned earlier winning time times in the unpaced races at Boston and NYC have not dropped much. Don't forget Rod Dixon

Who is Rod Dixon? For the uninitiated....

Ed - did you ever read any books about how to be a great feature writer? If not, how did you get to be so good?

Great question! Yes, I read plenty but I shouldn't tell you otherwise you'll steal all my secrets. One really good book I will tell you about is The New New Journalism, which is just interviews with great writers.

Dr. Joyner, what sort of marathon time is Bekele capable of considering his 5k and 10k PRs?

If you take 10k PR times 4.6 or 4.7 that gives you a range of what is physiologically possible, so the answer is close to 2:01

But hang on... that only works if you think that somebody has an equal capacity for 10k and marathon. Some people are better suited to one or the other. No?

How did you start writing for the New Yorker?

Pitched them a lot. Found an editor who liked my stuff. Found a story they liked. Worked my arse off. That kind of thing! It's an incredible place to write for. They really love good stories, and they work so hard with you to make yours the best it can be.

Is there an ideal height for a marathoner?

There's a lot of good heights, weirdly... Wilson Kipsang's 6ft as is Dennis Kimetto. Sammy Wanjiru was 5 4''. So, I don't think there is an ideal height. Probably not seriously tall....

Could a woman accomplish this feat? In the current state of human evolution, are only men in possession of the physiological and genetic advantages to go under 2:00?

I don't think so because 15 minutes is a lot of time to make up, but people are always wrong about the human body.... It would blow my mind if a woman did it one day.

What is the most impressive/insane workout you witnessed while reporting this book?

18 x 2 minutes sprint, one minute jog. At 8500 feet, up and down hills, on rough roads. 60 guys started it, five guys finished it.

I did not see what Ed saw, but back in the late 70s I saw some people do things like 4x800 in 1:55 with 5 min rest. Saw Craig Virgin break 4 min for a 1600 doing a 1600/1200/800/400 ladder of intervals in the summer of 1981.

Holy cow.

That is some workout.

Kenyans were all about getting their fast sections really fast.