This weekend, Nike set up an event where they declared three athletes would execute the worlds fastest marathon.

And some of these are things you’re free to do yourself.

Those tweaks helped Eliud Kipchoge run 26.2 miles in an unprecedented two hours, 24 seconds.

The officialworld recordstill stands at 2:02:57, because Nike didnt follow theIAAFs rules for record-eligible races.

They knew that, of course, and achieving an unofficial record is still a big deal.

Its possible, but not probable, they said.

So here are the factorsbesidesyour strength and skill as an athlete that can affect how fast you run.

Put these to use in your next race:

Pick a day with cool weather.

Most people will run their fastest on a45-degree, overcast day.

You cant control the weather, but you’re free to decide when and where you will run.

If youd like to beat your personal best time, dont race in the middle of the summer.

Youllrun 20 percent slower on an 80 degree day, for example.

Pick a race in the spring or fall instead.

Run on flat ground.

Hills can really slow you down, even if youknow how to run themwithout getting tired.

Then look up theelevation chartand see how flat it really is.

If you must choose something with ups and downs, consider where they fall in the race.

If you run fast, youre actually creating a little bit of wind resistance for yourself.

venture to hide from the wind by running right behind somebody else.

Keep up with your pacers.

In Nikes marathon, Kipchoge ran in a pack with six other runners at all times.

These other runners gave him a wind break but also a psychological boost.

Since you and I arent setting records, we can take advantage of pacers without breaking any rules.

In your race, just insert yourself into a mini-pack thats running about the speed youd like to match.

Most big marathons will have pace groups available for different goal times, so take advantage.

Thats your pace group leader.

Drink water but dont stop for it.

Dont run a step more than you have to.

Kipchoge and his teammates followed a specific path through their race track.

So take each turn on the inside, or else youre adding unnecessary distance.

Finally, pick the right shoes.

Both have bouncy foam that acts a little like a spring.

Almost any shoe willgive you a little bit of bounce, especially if its made with EVA foam.

This isnt likely to make a big difference to your overall running time, although thats a complex calculation.

Shoes with more foam may give more bounce, but be heavier, for example.