You just finished a 5K race, but your watch says you ran 3.22 miles, not 3.1.

Was it really a 5K?

Or maybe you finished your half-marathon with a race result of 2:02:10 but your watch says 1:59:59.

Can you tell your friends you ran a sub-two-hour half?

What is the difference between gun time, chip time, and watch time?

This is also sometimes calledclock time.

If you are trying toactually winthe race, you may need to care about gun time.

But for the rest of us, gun time doesnt matter at all.

Most of us can just forget about gun time entirely.

Its not for us.

This exists because of exactly the scenario I mentioned above, where theres a crowd at the start line.

In that case your marathon could have a 4:40:00 gun time and a 4:30:00 chip time.

The timing system registers a data point whenever you cross a timing mat on the ground.

There is a timing mat at the start and another at the end of the race.

But Ill discuss some issues with this assumption below.

But its often not.

Some of the reasons your watch time might be wrong:

Your watch auto-pauses.

Your watch will pause your run when you stop, and resume recording when you move again.

But during a race, stops arent free!

If you stop to spend two minutes in a porta-potty, thats still part of your race time.

Your app (such as Strava) might report a moving time.

Same idea as above, but it happens even if your watch recorded the whole thing.

Strava shows this run as taking 1:17:02.

I guess it took me 26 seconds to tie my shoe.

Turns out the timing service had accidentally added three minutes toeveryonestimes.

They noticed the error pretty quickly, though, and my official time was soon updated to 9:29.

So if your official race result iswayoff, consider speaking to the race organizer.

The first thing to check is whether the race course was certified.

(Most are.)

The process ofcertifying a race courseensures that the course has been measured to be the correct distance.

And that distance is nearly guaranteed to be shorter than most runners actually run.

you’re able to read the USATF course certification guidelineshere.

(Emphasis theirs.)

How do you find the shortest possible route?

You should measure the course following the same route as that hypothetical string."

If you think your race course was short, drop a line to the race organizer.

What counts as my PB?

Your PB, or personal best, can be whatever you want it to be in your heart.

This is where the distance issue comes up.

This is why we distinguishrace PBsfromtraining PBs.

So when another runner asks for your 5K time, they mean a race.

you could proudly and accurately cite your chip timein our example, 30:03.

I believe in you.