Overanalyzing My Poor 1/2 Marathon Performance
This past weekend I ran the Ohio Health 1/2 marathon. If you’ve been following along with my journey from fat to fit (https://wjgilmore.com/articles/10000-pushups) then you know I’m a big fan of tracking things. Like everything. All the things. My approach to training for the 1/2 marathon was no different and so based on all of the data I’d compiled I was feeling very confident I’d break my previous 1/2 marathon personal record of 2:27:03.
Calculations based on prior runs led me to believe I’d finish in under 2:15, and ideally at 2:11. Furthermore, although I was already in pretty good shape last October when I achieved the PR, these days I’m in far better shape both in terms of endurance and overall body composition. Finally, this time around I actually had a strategy which was more involved than merely surviving the race (more about this in a moment).
But as Mike Tyson famously said, “Everybody has a plan until you punch them in the mouth.” I wound up finishing in 2:29:40, and more than two days later I’m still trying to figure out why I ran so poorly. But rather than let my mind wander aimlessly I figured I’d do what I do best and completely overanalyze the situation. Let’s start with the numbers:
| Mile | Average Pace | Cumulative Time |
|---|---|---|
| 1 | 10:28 | 10:28 |
| 2 | 10:07 | 20:35 |
| 3 | 10:10 | 30:45 |
| 4 | 10:11 | 40:56 |
| 5 | 10:24 | 51:20 |
| 6 | 10:19 | 1:01:39 |
| 7 | 10:10 | 1:11:49 |
| 8 | 10:50 | 1:22:39 |
| 9 | 11:06 | 1:33:45 |
| 10 | 11:53 | 1:45:38 |
| 11 | 12:49 | 1:58:27 |
| 12 | 13:13 | 2:11:40 |
| 13 | 14:04 | 2:25:44 |
| 13.1 | 3:56 | 2:29:40 |
With the help of my dear friend Claude I used numpy and matplotlib to create this graphic:
I ran the first 10K in approximately 1:04 which isn’t a PR but was close to it (on March 21 I ran a 1:00:45 10K which included a crushing incline in the last mile). I felt great throughout this first leg, like Superman really. In fact I wound up running mile #6 faster than mile #5, I think largely because I was certain my training partner and sometimes nemesis Charlie was in my sights. The thought of passing Charlie around the mile #7 marker was so tantalizing that I started grinding up High Street with the goal of reaching him on the corner of Lane and High just ahead of the mile marker. I wound up catching him just following the turn, only to realize it wasn’t Charlie after all.
It turns out Charlie finished the race in 1:58, so by mile #6 he was well ahead of me and his evil twin.
Despite the letdown, I ran mile #7 even faster than mile #6! I distinctly remember this point in the race, and don’t recall any particular issue. But as you can see in the pace chart on mile #8 the wheels came off. The question is… why?
My 1/2 Marathon Training Regimen
Building on the success of 2025 I was determined to continue exercising on a pretty rigorous schedule, additionally stepping up the pace (no pun intended) with regards to running activity. I did exactly that, logging 25 running sessions and 94.58 miles in 2026 (this does not include the 13.1 miles run during the 1/2 marathon). Along the way I completed several long runs, including:
| Date | Mileage | Total Time | Pace |
|---|---|---|---|
| Feb 21 | 6.22 miles | 1:11:58 | 11:34 |
| March 21 | 6.1 miles | 1:00:45 | 9:58 |
| March 28 | 9.96 miles | 1:47:46 | 10:49 |
| April 11 | 8.35 miles | 1:22:45 | 9:54 |
| April 16 | 4.25 miles | 42:04 | 9:52 |
In addition to these runs I also ran 7 5Ks, 3 10Ks, and a series of other runs of varying mileage. I’ve also completed 3,180 pushups and 1,645 squats YTD, as well as more punishing stairmaster workouts than I’d like to remember. I’ve also been lifting weights, and on March 8 participated in the Arnold Fitness Expo Pump and Run where I managed to benchpress 150 lbs 16 times and ran a 5K in 27:36 (my current PR).
I am cognizant of not running a full 13.1 miles as part of the training, and perhaps that was a mistake. But I’ve run the 1/2 before and because of it knew exactly what I was up against, so I’m not going to beat myself up too much over this omission.
I’d also maintained a pretty strict diet in the weeks heading into the race, and further dialed it in on race week. My diet in the days ahead of the race consisted of: chicken, rice, potatoes, grilled vegetables, and fruit. The morning of the race I woke up at 5am and at 5:45am ate one cup of yellow potatoes. Approximately one hour before the race I drank a small bottle of zero calorie gatorade. In fact because I track everything I eat in a spreadsheet I can report exactly what I consumed in the 48 hours prior to the race:
| Time | Date | Food | Quantity |
|---|---|---|---|
| 8:20 AM | 4/23/26 | black coffee | 1 cup |
| 8:20 AM | 4/23/26 | greek yogurt | 3/4 cup |
| 8:20 AM | 4/23/26 | strawberries | 3/4 cup |
| 8:20 AM | 4/23/26 | blueberries | 3/4 cup |
| 12:00 PM | 4/23/26 | Chicken and rice bowl | Opa leftovers |
| 12:00 PM | 4/23/26 | m&ms | snack pack |
| 7:00 PM | 4/23/26 | boneless, skinless chicken | 4 oz |
| 7:00 PM | 4/23/26 | yellow potatoes | 1 cup |
| 8:00 AM | 4/24/26 | cottage cheese | 3/4 cup |
| 8:00 AM | 4/24/26 | black coffee | 1 cup |
| 8:00 AM | 4/24/26 | blueberries | 1/2 cup |
| 1:00 PM | 4/24/26 | boneless, skinless chicken | 4 oz |
| 1:00 PM | 4/24/26 | yellow potatoes | 1 cup |
| 5:00 PM | 4/24/26 | stella artois | 1 slim can |
| 7:00 PM | 4/24/26 | boneless, skinless chicken | 4 oz |
| 7:00 PM | 4/24/26 | yellow potatoes | 1 cup |
| 5:00 PM | 4/24/26 | stella artois | 1 slim can |
| 5:45 AM | 4/25/26 | yellow potatoes | 1 cup |
| 6:30 AM | 4/25/26 | zero cal gatorade | 1 small bottle |
I don’t track water intake but drink on average 120oz to 150oz of water every day, which is the equivalent of 4-5 30oz Yeti tumblers.
Race Morning
There was nothing unusual about the morning of the race. I planned on waking up at 5am and so went to bed around 9pm. I didn’t sleep particularly well but this isn’t unusual the night before a race. The night before the race I set everything that I’d need out on the kitchen table so the next morning wouldn’t be frantic. I woke up at 5am, showered, make a small cup of coffee, at 1 cup of baked yellow potatoes, drank perhaps 12oz of water, and then headed outside right before 6am because Charlie was coming to pick me up.
Before each race or when I travel for work I leave a note for my wife and kids, and this time was no different:
Yes I call myself The Machine on race days (and other days too). I have no idea why it looks like I’m carrying a tomahawk and a giant sucker. Those were supposed to be my fists raised in glorious triumph.
My Race Plan
As documented here I felt like I had a pretty good race strategy in place. The plan was to do something called a negative split in which I would start out relatively slow and then run at a slightly faster pace as the race progressed. In the best case scenario the pace chart would look like this:
- Miles 1–3 @ 10:30
- 10:30 = 10.5 min
- 3 × 10.5 = 31:30
- Miles 4–8 (5 miles) @ 10:05
- 10:05 ≈ 10.083 min
- 5 × 10.083 = 50:25
- Miles 9–11 (3 miles) @ 9:50
- 9:50 ≈ 9.833 min
- 3 × 9.833 = 29:30
- Miles 12–13.1 (2.1 miles) @ 9:30
- 9:30 = 9.5 min
- 2.1 × 9.5 = 19:57
If executed exactly as specified then my finish time would be 2:11:22. Note though I said “in the best case scenario”. I didn’t actually think I’d be able to keep this pace however I thought it was directionally correct because on the earlier 8+ and 10 mile runs I was able to improve pacing considerably as the run wore on.
Immediately before the race (while in the corral) I ate 4 GU Energy Chews. At approximately mile 3.5 I consumed one GU energy gel (salted caramel), and did the same at approximately mile 7. My plan specified a third was to be taken at mile 10 however my performance starting at mile 8 degraded to the point that frankly by mile 10 I was so dejected that I neglected to follow the plan. In hindsight this was probably a terrible mistake and possibly cost me a PR.
So What Happened?
The short answer is I still don’t know other than to suppose I “bonked”. Distance runners and cyclists use this term to describe what happens when one’s glycogen stores become so depleted that performance drops off a cliff.
If this is correct, then why I bonked is the real question. I felt fine on March 28 running the 10 miler, and also ingested two GU packs during that run. I will however note one primary difference between the runs, which is that during the 1/2 marathon my feet inexplicably started to hurt badly around mile 8-9. I don’t understand why this happened; my running shoes (Saucony) are not new, but I track their mileage and don’t believe there are more than 400 miles on them. Regardless, I’ve already bought a new pair of Saucony’s and officially retired my current pair following this race.
I also think it is worth noting this is the first 1/2 marathon I’ve run with music, and feel like that contributed (perhaps quite a bit) to my unexpectedly fast starting pace. Usually I listen to podcasts when running, or financial news channels like CNBC or Bloomberg (I swear I’m fun at parties). But this time I figured I’d change things up a bit and perhaps doing so was a mistake. In case you’re interested here is a screenshot of the first 15 or so songs on the race day playlist:
Yes that is Freakshow on the Dance Floor in the first spot. Told you I was fun! Even so, for the next race I think I’ll revert to my usual audio selection. Just for laughs I mapped the playlist to my pace chart:
Heart Rate
Regarding the increased starting pace, the music, and the general excitement associated with running a race with 10,000 of your closest friends, I did spend some time examining my heart rate respective to previous long runs. Sure enough during the 1/2 marathon I was clearly maxxed out for a much longer duration of time than the 10 mile run.
What Will I Do Different the Next Time?
That’s a great question, because right now I’m not sure other than to go about my training in a more deliberate way. The day after the race I bought the book “The Norwegian Method Applied”, by two-time Olympian Marius Bakken, and plan on incorporating some of his strategies into future runs. I certainly don’t feel overtrained or exhausted or anything like that right now.
My next 1/2 marathon race will be August 23, although I think I’m going to run a few 13.1 milers between now and then and methodically review my pace. I also wonder whether the 100 calorie (22g carbs) GU gels are enough. ChatGPT says the typical 1/2 marathon runner should be ingesting 30-45 grams of carbs per hour, but I’d imagine the actual correct number is going to vary a bit per runner.
On May 23 I plan on running a 13.1 miler around my neighborhood, and will subsequently update this blog post with the results.