What Does it Feel Like to Bonk in a Marathon?

I’m having a pretty decent day so far. I’m halfway through the Indianapolis Monumental Marathon. I’ve had a side stitch since about mile 5, but it’s not controlling me. With some deep breaths, I can make it go away and maintain my pace. I can’t eat an entire energy gel at once, or the pain gets worse. I’m now eating the gels in half portions so I can manage the stitch. This has me nervous, but I still feel okay. I continue with this strategy for the next 5 miles.

At mile 18, I might be in trouble. I’m now counting down the miles - doing math in my head to see how many minutes until this race is over - not a good sign. I’m not bonking yet, but I know from my training that this isn’t looking good. I down an extra energy gel to hold on a little longer.

At mile 19, I get to a long downhill. I’m back to hitting my goal pace, but I can tell this is bad news. I feel like I’m digging deep to finish the last mile of a 5k, not running the 19th mile of a marathon. My side stitch is unbearable at this point. Deep breathing seems to make it worse. Slowing down helps a bit. But I can’t slow too much. I need to keep my pace up so I can break 3 hours.

Can I still break 3? I was on 2:55 pace earlier; I just ran a 7:00 mile, so I’m only 10 seconds off pace. I still have 5 minutes of buffer. Maybe I can do this.

I split my watch for mile 20.

8 minutes and 12 seconds. I just lost over a minute in one mile. My face is feeling numb, my legs are on fire, and I’m starting to feel cold. I have a side stitch but I’m also incredibly hungry. I can’t really focus on anything; I feel like my body is diverting resources away from my brain. I’m slowing, but maybe I can still make it. I’ll keep going slow like this and maybe I can hop in with the 3-hour group when they pass me.

I take another energy gel from an aid station in hopes it will help my energy. My side stitch immediately gets worse. I take some deep breaths and slow down a bit to let the pain calm down. It’s too late. My stomach is constricting, and I feel the muscles under my chin start to tighten.

Before I can react, I’m starting to hurl. I pull over to the side of the road and do my business. Once all the contents of my stomach have been emptied onto the grass, I’m able to pull myself together and start walking.

Now I can really feel how tight my legs are. Every step pulls on my calves and hamstrings like I just did a speed workout.

I haven’t noticed the weather until this moment. It’s chilly, overcast, and windy. I’m cold. I really wish I didn’t ditch my gloves a few miles back. I need to start running, or I’m going to freeze out here.

I turn back and see the three-hour group in the distance. I’ll start jogging now, hopefully getting warm enough to stick with them. A minute later, they’ve caught me. I latch on, but this pace feels unsustainable. I quickly start breathing very heavily. My legs stiffen up, the dizziness, and facial numbness are starting to come back.

I can’t do it. My three-hour attempt is over.

I’m forced to walk again to avoid throwing up a second time. I grab some energy gels from the aid station. I try the first one, but it won’t go down. My mouth is so dry that I can’t swallow, and there’s no water at this aid station. I’ll try again when I pass a water station.

My watch beeps. I just did another mile! How far have I gone?

21 miles.

How is this possible? That last mile felt like an eternity. There’s no way I can do this for 5 more miles. I grab a little water at the next aid station and put down part of the energy gel. I’m able to start slowly jogging again. This time it feels more sustainable. My legs are on fire; I’m still dizzy, and I can’t believe how much effort it’s taking to maintain just a trot. I keep going until mile 22.

Now I can do some mental math:

4.2 miles to go. At this pace, that puts me at around 3:10. If I run under 3:10, I can qualify for Chicago. I have 2 more gels in my waistband, and I think I’ll pass another fuel station. I think I can keep going like this.

I suddenly get a searing pain through my left calf as I start to stumble. My calf has cramped up, and my ankle is stuck in a plantarflexed position. With a little walking, it loosens up, and I can start jogging again.

As I continue my cold, sweaty, dizzy trot to the finish, my calf cramps a few more times. Between cramps, I try to pick up the pace to keep my 3:10 goal alive.

Finally, I can see my hotel building near the finish. I think once I get there, I just need to make it another 200m. It looks about a mile away.

I check my watch. 24.1 miles.

At this pace, I think I can still break 3:10. I continue my walk/run until I know I’m close. I turn the last corner and check my watch.

3:09:00. I have 1 minute to go about 200. I know I can make it.

I tough it out, limp my way through to the finish line for a time of 3:09:52. I can’t believe it. I made it by 8 seconds. I never thought I’d cut it this close.

In a daze, I make my way through the post-race celebration. A race volunteer places a medal around my neck. I grab a Gatorade, a granola bar, and a few other snacks. I take a space blanket and shuffle down the block to my hotel. The only thing I want to do is get out of these shoes, get in a warm shower, and eat my snacks.

A few minutes later, I make it up to my room where I can finally relax. The next few hours revolved around getting fluid and food back into my system.

I did not run as fast as I wanted to. The last 10k took me almost an hour. I can’t even count how many times I wanted to quit. But I made it. Just fast enough to do it all again next year.

We’ll see you at the 2024 Chicago Marathon.