Running 100k for the first time, in 20 hours


I did a hard thing, a bit last minute.

Mostly to hit a reset button, turn the volume up, send myself the message.

It solidified lessons that I carried all year, so it worked.

It's not as hard is it seems.

It re-ignited my appetite to do more.

This year for my birthday I wanted to send myself a message, my last months were kind of low energy, I wanted give myself a fresh jolt.

I chose to do this 100k on my birthday because it’s a very “energy and time expensive" thing, it would be hard to justify "indulging" in this any other day.

Also, for the last few years I’ve been doing things that are different these on birthdays, before I chose silent retreats though or spending time off grid in nature(more on these later). Last year I wanted to go a bit more on the offense.

At the beginning of the year I read about the Japanese concept of misogi.


is a Japanese “Ritual of purification", the westernized version seems to go like:

pick something hard and scary, once a year, that you think has a 50% chance of succeeding.

The point being if you take part in this challenge it will color the rest of your year.

I never ran a full marathon so I thought that would be a good start, and ideally I’d try to push for 100k.


I’ve also recently read Goggins ( listened to the audiobooks) “Can’t Hurt me” and “Never Finished” and watched a tonne of interviews.

As Joe Rogan put it very eloquently “this shit makes you want to run through a brick wall”.

While he can seem almost comical with his shirtless running and screaming, I do agree he is misunderstood and he managed to distill some very important lessons that can be useful for most of us.

More on these later though, in a separate article.

Prep Work

I read up on how to approach the run and asked others who’ve ran or walked 100k in one day before.

According to runner articles, ultras are all about fueling.

Physical prep

I ran at least 3k a day, every day, since December, I stopped in April because of knee pains.

I also:

- worked out 2-3 times a week, strength training, and at that time recently started deadlifting (about 130kg, 140 kgs reps on trap bar)

- did 1 timed run a month before: 3k 17.49 min 150 heart rate, to check for speed.

- plus I usually have at least 13k steps per day, with runs included

- Longest I ran before was a half marathon I think, I never really counted thees things before.

I thought I should be better prepared but having read how Goggins did his first 100 miles I was curious how this would all feel, and it was only 100k not 100 miles, I was curious what would happen.


I was living in Lisbon at the time, I scouted some routes on smaller runs. There’s a lot of water fountains next to the river so I decided I’ll go along those so I don’t have to carry much extra water with me, and use those as my refuel stations.


The previous day I bought some energy gels, some with caffeine, packed salt,  electrolytes, cliff bars as snacks, and some nicotine chewing gums (good for workouts, more on this later though) 

I tried to carb load a bit the night before, cut my nails and packed some sunscreen too.

Gear to carry

- 1 big marathon belt

- 2 smaller belts, one with keys, other with electronics charger etc

- 2 water bottles

- vaseline for chafing

- fresh socks - to change every 20 km

- tape - just in case

- snacks

- hat to protect against sun

For shoes I had some random trail running shoes (found out later it's not the best choice but they worked well)

The run

I started a bit after dawn, first 40k was quite ok, I took my time, shot videos, took it easy to see how my body would react.

I planned the run loops so I can reach my house every 40 km or so, so I stopped, took a shower, and refueled with snacks.

50k shoulders

The weirdest pain I felt was surprisingly shoulder pain around the 50k mark, apparently it’s a thing for people who are not used to running long distances. At some point I was carrying one arm with the other so I wouldn’t have to hold it up. Luckily the pain went away after a while.

Loop 2 - 60k

I thought I’d take a break when it’s the hottest, between 2 and 4pm, but I miscalculated.

It got hot, the sun was blasting me and I went full Goggins, no shirt, trying to fight it.

That was dumb, but I ultimately won, the sun went down, i stayed up.

I also stopped and ate some Pastel de Nata’s - bad idea since apparently the digestive system shuts down on long runs, it felt like carrying rocks in my stomach for a few hours.

Around 6pm I had to take a longer break, I was starting to get dizzy and when I checked my face I was turning red af.

I knew this feeling though, I think it was a mild heat stroke, I had this before in Asia from a hard workout in the sun. I remembered I have to reduce my core temperature fast, otherwise my plans might get messed up. Luckily my gym was on the way, and they had an aircon waiting room so I sat there for 45ish min until I felt better.

The walls

After 60k, each 10 felt like I was hitting a new wall, but I would rest a bit and convince myself I can do 10 more.

Step by step

After each rest session it was quite brutal to get up, my legs felt like they were falling off at times, but then once I started walking each step felt lighter than the previous. Whenever I felt I couldn’t take it anymore I took some energy gels with caffeine, that always gave me a little a boost. The nicotine lozenges helped a tonne too.

I also found glucose tablets in a pharmacy that were great, whenever my legs turned to lead I'd pop half of glucose pill and I could almost feel them fuel back up.

The 80k wall

I thought if I reached this far I might as well do all 100. This was a big turning point, where I had 20k left to return to my apartment, so from this point on I was running towards home. It got dark though, windy, and a bit cold, but that was great since I wasn't sweating so much.


In between my legs and armpits were the worst. 

I also kicked something around the 60-70 km mark, my toes got bloody, but my legs were going numb usually after picking up pace, so that didn’t bother me that much.

The 90 k wall

The worst wall.

I pushed myself and ran quite fast so I could get the 90km before midnight. I missed it literally by seconds, sat down after to rest, but then getting up was really fukin hard. 

I thought I’d have to quit, I was running low on snacks and in general felt like I got beaten up. Luckily I had a good friend, Rim, bike out and accompany me on the last 10k.

I walked a lot, and I remember the pain was brutal.

The last 10k took me almost 3 hours to do.

On the final stretch I showed Rim the bday message Rogan got from Goggins, laughed through it, and it delivered a perfect final boost.


I finally reached 100 K around 2:49 AM.

- 100 km

- 20 hours 7 minutes

- 12 min pace average lol - a brisk walk might've been a better strategy

- 9196 Calories

- 115.991 steps


My feet were a bit bloody, hurting, I was walking like how I imagine walking at 100 yo will feel like.

I couldn’t sleep for another 4 hours from the adrenaline, likely all the caffeine didn't help either, so I decided to get a long bath and get philosophical on my instagram. 

Reflected on the why and started putting it into words, sharing some of it, thinking about "why do anything", "why do hard things". Articles on these later.



First 2-3 days I could barely walk and realized my big toenails would fall off - apparently it's common, almost a badge of honor for long distance runners.

After the 3rd day I could go to the supermarket, #geriatric pace, but felt like a big achievement.

I felt weak for a long while, I suspect this was also because I let myself go after, thinking I should rest more, and I think I overdid it. Next time I’ll start light workouts sooner.

Didn’t weigh myself unfortunately but I visibly lost a good amount of muscle, especially in my chest and arms, I'd guess around 5kgs total.

Other than that it all went surprisingly of ok.


I Definitely got the boost I was looking for.

The “one step at a time” mindset got etched into my brain, just as I was hoping. I think of it as a brain tattoo. I wonder how long it will last. Will probably have to re-draw it next year, for good measure.

It's interesting I could conjure up the "LFG" attitude after the run when dealing with something hard to get me in the “push” mood.

I was most surprised that ultimately it didn't feel that hard.

Obvious question is what else could I do, that I'm not doing, because... why?


Interesting that people seem to take notice of it, even experienced runner friends, and it sounds like a big deal.

Looking back it doesn’t feel like that.

When people said wow must've been so hard  I was thinking daily life is so much harder lol.

I also met some savages since, that reply "cute" when I tell them, at some point I was embarassed to even share to story as an "achievement", but hey, we all gotta start somewhere.


Again, this etched the principles in my brain, why this was “easy”:

- finite duration / pain

- clear outcome / finish

- small steps, small distances, always focus on just making it to the next

It’s cool to hear and read these, but experience really helps solidify the ideas, and actually understand what they mean.

Also the obvious thought is, what if most things in life are like this? You just bite the bullet voluntarily for a bit, then rest.

Journal entry

I found an a entry from a few days after

Just found out I might be rekt for a few weeks.
Feels crazy. Can't believe it. Might’ve mini broken a few mini bones.
What a rush though.
On the other hand it doesn’t feel like a big deal. I think Vipassana was much harder in some sense, or a "bigger trip".
I feel like I burnt out all my anxiety,
I have no capacity to feel anxious about anything.
Wish i was more creative tho.
Need to rest.
Take vit C.
Cuz apparently ultra runners often get sick after?
Definitely calmer, will figure everything out. “Keep hammering“
CHAFING - bad af. Legs, in between legs, underarms. still ouch.
“I dedicate this to my inner child.“?
Viciously make space for creation.
Also Rim was great. People are great. Don’t isolate.

Proper Training

All in all I think it was kind of stupid to do it without proper training though.

This was another lesson, 

Don’t “muscle” things. 

Prepare better.

“It’s not a sprint, it’s a marathon an ultra marathon.
Definitely a new perspective on life.

6 months after

At the 6th month mark I decided to do something similarly “hard” to commemorate this, so I started building this blog, that I’ve been procrastinating on for about 10 years now.

I'm writing this to reflect, remind myself of the experience and I can’t wait to do the next hard thing.

Let me know on the socials if you know of some interesting challenges.

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