Archive for the ‘5k’ Category


#23 – Two Races in One Day

1 July 2007

Many running events host multiple races at the same time, e.g. a 5K and 10K taking place simultaneously. When registering we’re forced to choose which distance suits us best for that particular weekend. The Reeds Lake Run, however, offers a twist on the usual 5K or 10K option: runners can do both!

Intrigued, I signed up for both races and then had to figure out a plan. The 5K starts at 8:00am and the 10K at 8:45am – both start and finish lines are close to each other. I decided to run the 5K as hard as I could, then run a relaxed 10K just to see how my body handles back-to-back racing.

Perfect weather dawned over the course as my wife and I walked through the host downtown of East Grand Rapids prior to the race. Temperatures were in the mid-60’s under a sunny sky as Amanda took up a position to photograph the start:

Right off the bat there seemed to be a lack of energy in my system; I can’t explain why and before the race I was reminding myself that this feeling could be deceiving. Unfortunately, the body doesn’t lie. I clocked a 6:45 first mile and two facts were foreboding: 1) I’ve run faster first miles in a 5K, and 2) I felt as exhausted at mile 1 as I usually feel at mile 2! It was going to be twice the suffering just to finish, knowing that my time wouldn’t be what I’d hoped for. Somehow I talked myself to continue pushing hard, hoping for a second wind.

No such luck. Practically staggering across the finish line, I glanced at my watch to see that I’d finished in 21:37, the second-slowest of my four 5Ks thus far this year. As you can see in the image above, I was really desperate for oxygen at the finish! Looking at that photo at least everyone else is in pain, too. 🙂

Not nearly as much in pain were the race winners:

Wow are they fast! They had half an hour to recover for the 10K (the winner of the 5K wound up winning the 10K! Unreal.) while I had just 23 minutes. I walked to the food table and drank a cup of Gatorade and chatted briefly with Amanda before heading off for the start of the 10K. Clearly I’m feeling much better by the time the horn sounded for this second race:

The enjoyment of the first two miles of the 10K was such a contrast to the suffering of the 5K! I ran a 9:30 first mile and a 9:00 second mile, not by intention; I was just “going for a run” and happened to notice that was my pace. Since I’ve never run a race before without trying to run my fastest, this was a new experience. I was able to look around and take in the surroundings – the mid-morning sun over Reeds Lake, runners chatting with their buddies, spectators sitting on their lawns as we ran past their driveways.

Speaking of spectators, the residents of East Grand Rapids do a great job. One house had set up their own aid station; a couple folks were holding their garden hose at the ready in case any runner wanted a shower (I took them up on the offer both times!); a high school rock band was performing in a driveway! My memory has some vague memories of these things from the 5K, but I wasn’t able to really enjoy or appreciate them until I ran the 10K.

Running two races was an experiment for me and around mile 5 I began to realize one of the effects: my legs started to feel numb! Not tingly, but I was having trouble commanding them to move any faster or slower – it’s as though the control system for my leg muscles simply crashed. Somehow they continued to function on autopilot until the finish, when my ego was threatened.

Amanda had told me beforehand that she planned to record a video of me at the finish. Cruising down the home stretch I spotted Amanda in the distance when I heard three young women behind me start to encourage each other: “C’mon, let’s pass some people!” “Let’s sprint, go go GO!” Afraid that Amanda’s video would show me getting passed by three gals at the finish, I found the adrenaline necessary to accelerate into a sprint of my own and carry it across the line; the women were safely well behind. 🙂

(You can see the resulting video on my personal blog.)


#12 – Pushing the Pace of Physics

5 May 2007

Last weekend I ran in the Road Ends Trail Run and despite achieving my goal, I noticed that my leg speed just wasn’t there. Thursday I hopped on a treadmill to get a feel for my stride rate (steps per minute) and sure enough, my recent lack of training had slowed my legs down a bit. Yeah, speed work is good.

While running pops between a 6:00 pace and a 10:00 pace I noticed that as the treadmill sped up, it went quickly from 10:00 to 9:00 but more slowly from 7:00 to 6:00. My brain was too tired to do math at the fast pace, but when I slowed down again I realized that this made sense – speed does not correlate with pace in a linear fashion. For example:

10:00 pace = 6.0 mph, 9:00 pace = 6.7 mph, a difference of 0.7 mph;
7:00 pace = 8.6 mph, 6:00 pace = 10.0 mph, a difference of 1.4 mph!

What this means is that the faster you run speed-wise, the harder it is to reduce your minutes-per-mile pace because speed and pace have an inverse power relationship, like you see below:

The blue line is pace relative to speed. I also added a green line representing energy to show how energy is proportional to the square of speed, meaning energy has a parabolic relationship to speed. (For simplicity I used generic “energy units” as opposed to real units – like Joules or Calories – where 100 energy units equates to a 4:00 pace.)

Since most of us runners measure ourselves using minutes-per-mile pace rather than miles-per-hour speed, I created a plot showing the relationship of energy to pace:

This shows why running fast is so hard! The faster you go, the even more energy it takes to sustain that pace. Using the paces from my first example, it takes:

4 energy units to increase pace from 10:00 to 9:00
12 energy units to increase pace from 7:00 to 6:00

And just to show how tough it is for elite runners to push themselves to a 4:00 pace:
36 energy units to increase pace from 5:00 to 4:00

Wow! So cutting your 5K time from 30 to 27 minutes isn’t nearly as difficult as trying to improve from 18 to 15 minutes. This is why elite runners measure their performance to the second while average folks like me are content to measure to the minute or half-minute. Speaking of 5Ks, here’s how my performance has improved running 5Ks over the past couple years:

24:39 overall = 7:57 pace = 25 energy units (October 2005)
22:42 overall = 7:19 pace = 30 energy units (October 2006)
21:07 overall = 6:49 pace = 35 energy units (March 2007)

Looks like I’m pretty consistent; if I can improve another 5 energy units to 40 that puts me at a 6:19 pace, which would pass my goal of running a 20:08 5K (a 6:30 pace).

One way I can see an analysis like this helping runners in training is to provide more achievable goals. As we train and improve, initial results are going to come quickly as we cut large chunks of time off our race performances. If we expect such improvements to continue at a linear pace then we’ll only become frustrated. For example, my second 5K was two minutes faster than my first; however, I should not expect my next 5K to be two minutes faster than my last one. This may seem ironic but the faster we get, the “lower” we should aim our sights for the next goal.

Try it out! How fast were you running when you first got started, and how fast are you now? How many “energy units” is that? If you maintain the intensity of your training, you could expect a similar improvement in “energy units”. Of course the human body has limits to its energy output, which makes running faster even more difficult than just the physics of energy and speed!