Of all of the mistakes made while racing, pacing is the most consequential. Even a few seconds too fast in the early miles will cost you 10-30+ seconds per mile later. Not a good investment! Bill recently ran the Rock and Roll Philly Half Marathon and shared his splits with me.

"Couldn't have asked for better weather for the PDR. I finished with the time I was hoping under 1:53 but not quite the way I planned. Nonetheless it qualified me for a martini. My splits were: 8:41, 8:18, 8:23, 8:19, 8:30, 8:40, 8:36, 8:38, 8:35, 8:36, 8,31, 9:06, 8:55. Not sure what happened at mile 11 and 12 but couldn't keep the pace. That part was a little disappointing.”

First, congrats on running an MQ (martini qualifying) time, Bill! Cheers!

What do you notice?

Here, look again:

8:41, 8:18, 8:23, 8:19, 8:30, 8:40, 8:36, 8:38, 8:35, 8:36, 8,31, 9:06, 8:55.

So, despite absolutely nailing his pace for 8 of the 13.1 miles, he couldn't help but slow in miles 12 and 13.

His fate was sealed 4 miles into the run. While he was feeling great.

This happens ALL THE TIME to a majority of runners, but the effects are most pronounced in the marathon. Running one soon?

Pay attention to the following 5 tips.

1. Know Your Fitness.

The best way to know exactly what you are capable of is to run all out for a given distance. I mean, just go out and crush it. Run a race of about half the distance of your goal race all out and you'll have some really valuable data. Plug your race time into McMillan's Running Calculator and, boom, you get a fairly precise estimate of what you can handle for a longer distance race.

2. Read Your Body

Newbies have a tough time with this one, but they'll get it. Just takes some practice. I like to do a “systems check” continually throughout the race.

Am I as relaxed as possible? Gritting teeth, squinting eyes, shrugging the shoulders, clenching fists, and grimacing facial expressions have no place in your run.

How's my breathing sound and feel? Obviously this depends on the distance of the race, but in a marathon it should never be audible. (Ok, maybe in the last mile or two). In a 5K, I like to get through the first mile as quietly as possible. ;-)

3. “Is this Sustainable?”

Just keep asking yourself, “Is this sustainable?” How simple is that? That little voice in your head knows. LISTEN to it!!

4. Patience and Discipline

Two of my favorite terms regarding pacing! You MUST have patience in the first half of the race. You should NOT feel like it is a hard effort YET. Ideally, your pace remains the same but your effort progresses from easy to hard over the duration of the race.

Don't race like an 8 year-old. Seriously, practice some restraint. Good things come to those who wait. How many other ways can I say it? Be disciplined to execute your race plan. Don't get swept up in everyone else's insanity. Put the blinders on and run your pace. You can pass 'em later!

5. “This Is Too Easy!”

BREAKING NEWS: Just because you are in a race, doesn't mean you need to be on the verge of puking every step of the way.

Every single time I've run a personal best it's felt easy in the first half of the race. Coincidence? Hell no. It's because I was relaxed and in the moment. I knew my fitness going in. I continually felt I was running a sustainable pace. I deliberately held back and trusted my race plan. And every single time, it's felt almost “too easy” in the first 25% of the race.

Miles 1-9 in the marathon. Miles 1-4 in the half marathon. The first mile of a 5K. You need to have no doubt about the fact that you COULD EASILY run faster. But, no, you are committed to smoking the final 25% of the race and taking the hearts of those that weren't as smart. :-p

Got a good bonk or blow up story? I'd love to hear it - share below!