Race Report Worlds Deepest Marathon [English version]

[Svenska versionen av Race Reporten läser ni här: Race Report Svenska ]

All non-selfie photos are credit to becomingX and Sam McElwee.

Where do I even begin with this event? This is a race report, so I’ll focus on the race itself, but I must acknowledge the incredible work done by the organization at the Boliden Garpenberg mine to make this happen—and in such a way! Hats off, it was insanely well-organized in such a complex environment with so many people. And the mine operations were running as usual during the race! Wow!

Before the Race

We stayed at a hotel near Arlanda, and the night before there was a dinner buffet. I was feeling good and managed to eat a proper pasta meal. I figured I’d eat well since I probably wouldn’t be able to eat breakfast that early on race day.

The morning was rough. I woke up around 3:00 AM due to nerves, even though my alarm was set for 4:40 AM (bus departure at 5:45). I had a pounding headache. My son Sam had been home earlier in the week with a headache, so I was terrified I’d caught the same bug. I drank water, took painkillers (paracetamol), and tried to rest upright. Eventually, I had to throw up the pasta from the night before—nerves and a full stomach don’t mix well.

I was in bad shape. I walked very slowly to breakfast (which is very unlike me). I managed to eat a few pieces of fruit and pineapple, packed my gear, and headed to the bus.

The two-hour bus ride was mostly spent in a semi-sleepy, anxious state. But once we arrived and I met all the cheerful people in Garpenberg, I started feeling better and could drink some sports drink.

We had safety briefings and a logistics plan to get everyone down to about 1300 meters underground (1120 meters below sea level). First, a 1054-meter elevator ride (3 minutes), then a car ride for the last 300 meters. Everything ran smoothly!

Race Setup

It was a relief to finally reach my station and organize my energy supplies. I had extra batteries, salt, electrolytes, and took two more painkillers before the start

My energy plan is described in a earlier post, (in swedish, use an LMM if interested):

Energiplan Marathon

I had printed out Excel tables with lap times and pace calculations—since GPS doesn’t work underground. But it turned out that lap times and pace were displayed on a big screen at the finish line, so I didn’t use my lists. That became a challenge later.

My goal was 3:30, but I had been dreaming of pushing for 3:15 (4:37 min/km) if things went well.

The course was a 1.92 km stretch run back and forth 11 times. It had a 2% incline, about 40 meters of elevation gain per lap = 400 meters total. Constant up and down. It was 24°C with 72% humidity—pretty moist! (Garmin showed 27°C, but who knows how accurate that is.)

Start

Just before the start, they played a video with greetings from loved ones—very touching, but hard to absorb five minutes before the race. I chatted with others at the front about their target times—most were aiming for 3:15–3:30, same as me.

The race started. I didn’t chase the fastest runners but kept to around 4:30–4:40 min/km for the first lap. It felt good, though my heart rate was high (165 bpm).

irst lap: 4:38 min/km—perfect for a 3:15 pace. I ran alone but could still see the runners ahead. Only about five times during the race was I completely alone in the dark. Usually, you’d see lights or the turnaround point.

Second lap: 4:42 pace. Still steady. The first laps felt easy, legs were fine, heart rate high but manageable. Everyone was cheerful and cheering in the tunnel.

Soon I started lapping slower runners, which made it hard to track placement. You couldn’t tell if you were overtaking someone or lapping them.

First hour: average heart rate 163 bpm. Lap times slowly dropped. I later realized the pace shown on the screen was average pace—not lap pace! So I was running slower than I thought. A drop from 4:43 to 4:49 meant the last lap was much slower, maybe 5:10.

This gave me a false sense of security. It’s really hard to maintain a stable pace by feel alone, especially as a marathon newbie. I usually rely heavily on my watch during training.

The heat wasn’t as bad as expected. The tunnel had some airflow, and sweat didn’t pour into my eyes. The helmet was damp but didn’t bother me.

Mid-race

Around halfway (21 km), I started feeling slight cramps in my calves. Nothing serious. Legs felt fine, but I was getting tired. Five laps to go felt long.

I stuck to my energy plan: switching soft bottles (150 ml, 35g carbs) every lap. It took longer and longer to finish each bottle. Eventually, I barely finished one per lap.

Heart rate dropped to 155 bpm. I couldn’t push harder—or didn’t want to. I realized 3:15 was out of reach, so I settled for something between 3:21 and 3:24. Not ideal, but fatigue convinced me.

I didn’t manage to take extra fluids or gels, so I only drank 1.2 liters total. That’s about 80g carbs/hour. I did take an extra salt tablet, which helped me drink faster.

Between 20–30 km were tough mentally. Too far to push hard, fearing cramps. After 8 laps, with 3 to go (11 km), the fog lifted. That felt doable no matter what!

Average pace had dropped to 4:55. During lap 9, I realized 3:30 wasn’t guaranteed anymore! I had several laps slower than 5:00, which I hadn’t expected.

With 2 laps (8 km) left, I picked up the pace. It was motivating to chase a time instead of just surviving. I pushed hard on the second-to-last lap and gave it everything on the final lap.

I calculated at each km marker how many minutes I had left if I ran at 5:00 pace. It was tight! My calves were cramping constantly, but I could still run—just not fast.

I was sure I was running at least 4:30 pace, maybe faster. Heart rate hit 175–180 bpm. When I saw the finish line, I had 2 minutes left to hit 3:30. It was the closest thing to a sprint after a marathon.

I finished in 3:29:19! Placed 4th. You can see my finish on Instagram—my legs were jelly Instagram målgång

Fun fact

My son Sam made me go viral on a famous streamer’s livestream from the event! He wrote in the chat to watch for his dad (me), and the streamer Seepekay followed my story during the race and featured me in the broadcast.

Post-race thoughts

Beforehand, I’d have been disappointed with 3:29, but afterward I’m proud. I had to fight hard for it.

Winner: James Mason at 3:17:50. Mika was the top Boliden runner—great that Glencore didn’t take the top two spots. I think I was the fastest first-time marathoner—always something!

I spoke with the winner, an experienced marathoner with a PB of 2:31. He said he could’ve run under 3 hours above ground that day. That meant a lot—it suggests I might’ve been capable of 3:10–3:15 under normal conditions. 400 meters of elevation is a lot compared to a city marathon.

Not seeing pace was tough. With GPS, I’d never have let my pace drop below 5:00. It might’ve been a more even race. Funny thing: on the last lap, I thought I was running 4:30, but it was actually 4:58 😂😂

Almost everyone finished, so it looks like I’ll get a Guinness World Record on my résumé!

Definitely the most epic medal I’ve ever received! Garpenberg even mounted a metal piece on a drill core—so I got to take home a piece of the mine!

One sponsor printed numbered silver coins—I traded to get the one matching my bib number.

When I took off my shoes, my sock was bloody from a burst blister on my big toe. Didn’t feel it during the race—thankfully!

Analysis

Most interesting data: lap pace. First 21 km were solid. Then a big drop in motivation and pace between km 20–34. That’s why 4:58 felt fast at the end—after running as slow as 5:17 on lap 9!