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How did Keely Hodgkinson, the reigning Olympic 800-meter champion, react when she first heard about Faith Kipyegon’s planned attempt to run a sub-four-minute mile? “Half between ‘Oh my god, that’s absolutely crazy’ and ‘Wow… what if?”

That pretty much sums up the feeling here in Paris with one day left before Kipyegon’s Breaking4 race. Hodgkinson is in town to host the of the race, which will take place Thursday at 8 P.M. Paris time, 2 P.M. Eastern Time. So are a bunch of other top runners, including Georgia Hunter Bell and Jemma Reekie, who have been rehearsing with Kipyegon for their role as pacemakers (more on that below). The goal, according to Reekie: not just getting the pace right, but making sure Kipyegon is comfortable, and even encouraging her as they run.

A few final thoughts before the big day:

The Weather Gods

I flew into Paris today from Toronto, which has been suffering through a brutal heatwave. I didn’t get much relief. It was 95 degrees Fahrenheit this afternoon when I went for a jog along the Seine, and the sun was hammering down mercilessly. The forecast for this evening at 8 P.M.—exactly 24 hours before the race is scheduled to go off—is still 82 degrees. Tomorrow at 8 P.M. is supposed to be marginally cooler, with a forecast of 79 degrees.

A temperature that high would be an absolute disaster for a marathon. On the other hand, it would be heaven for sprinters, who tend to feel tight in cold weather and don’t have to worry about overheating from sustained exertion. Milers are somewhere in the middle. The Breaking4 scientific team figures a range of about 60 to 78 degrees would be ideal, so they’re not far from that. One option would be to delay the race by an hour to get a few degrees cooler.

They’re also hoping for wind speeds of less than about 7.5 miles per hour, humidity of less than 50 percent, and somewhere between 20 and 60 percent cloud cover. Humidity was close to 90 percent at times today, and tomorrow’s forecast currently calls for wind up to 9 miles per hour, with possible gusts up to 23 miles per hour. That too will be dropping as the evening progresses. Overall conclusion: the weather is a little dicey, and I imagine the Breaking4 team is considering its options right now.

The Drafting Plan

A few weeks ago, in my big round-up of the science of how Kipyegon will try to break four, I lamented that Nike was being cagey about its plan for pacemakers. They’re still not confirming the plan. They did put out offering some hints. For example: “Disruptions can make the smoothness of drafting go haywire; the choice to switch in runners midway through a lap can create micro-undulations in the air frequency, disturbing Kipyegon’s speed.” That strongly suggests they’re going to enlist one set of pacemakers to go all the way, rather than trying to sub in fresh pacemakers halfway through the race.

The press release includes a video showing (in their words) “one strategy they considered.” In others, we don’t for sure it’s what they’ll use, but it’s probably to consider it the leading candidate. Here’s a screengrab showing the formation:

Kipyegon is the yellow dot, running from left to right in the image. There are 11 pacemakers in this formation, which will require some impressive choreography. I’ve never seen a formation quite like this before, but the crucial difference between this event and the previous research is that Kipyegon will be circling a track, so the drafting has to be effective on curves too. (Apparently Nike proposed staging the whole mile in a straight line, but Kipyegon preferred to keep it on a standard track.)

In the scenario presented by Nike, the eighth and ninth pacemakers, running on the inside line behind Kipyegon, are slated to be female pacers—presumably Hunter Bell and Reekie. They would aim to make it through halfway then drop out, with the two pacers behind them moving up to take their place.

How to Watch

If everyone goes according to schedule—and admittedly that’s not guaranteed, given the weather—doors will open at Paris’s Stade Charléty at 11:30 A.M. Eastern Time on Thursday, June 26. Live programming starts at 1 P.M. Eastern, and the race is slated to go off at 2 P.M. Eastern. It will be streamed on Nike’s YouTube, Instagram, TikTok, and Douyin accounts, and also on Prime Video. More details about how to watch are available . And of course, whatever happens, I’ll be filing a report right after the race!

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