Challenge Fuji 5 Lakes Ultramarathon

Race Report 12: First 100k (actually 118k)

34th Challenge Fuji 5 Lakes Ultramarathon (第34回チャレンジ富士五湖ウルトラマラソン) : 21 April 2024

Whenever you mention to Japan to someone, one of the first things that will come to mind is Mt Fuji. There’s just something magical about this mountain.

A few years ago I took a trip to one of the lakes near Mt Fuji called 河口湖 (Kawaguchiko), and I was in awe of how incredible the mountain looked up close. Since then the lakes around Mt Fuji have become a favorite holiday destination of mine.

At some point I heard about an ultramarathon in this area that goes around all five of the lakes and I decided that this was going to be my dream race.

I applied for the Challenge Fuji 5 Lakes Ultramarathon in October 2023. Before this race the longest I had ever run was 70 km. The ultra gives you the option to run 3 lakes (62 km), 4 lakes (100 km), or 5 lakes (118 km). There is even the option to run a “Spartathalon” course which is a 120 km course done on a more strict time limit.

I wanted to do this properly. I wouldn’t have been happy if I entered the Challenge Fuji 5 Lakes Ultramarathon and do anything less than all five of the lakes. I had a 15 hour time limit to do this in.

The course map and elevation plot can be found below:

Course map and elevation plot.

To briefly explain the course, the start point is at 富士北麓公園 (Fuji Hokuroku Park). You run east to do a full loop of 山中湖 (Lake Yamanakako), run past the start point, go north to 河口湖 (Lake Kawaguchiko), run along the north of that lake, continue to run west on the north side of 西湖 (Lake Saiko), run once around 精進湖 (Lake Shojiko), proceed to 本栖湖 (Lake Motosuko) in the west, then return to the start by running east along the south side of Lake Saiko and Lake Kawaguchiko.

The course has some quite steep hills (especially the one right at the end). My plan, after assessing the course map, was to try to get the first half of the race done relatively quickly, slow down in the second half of the race, and aim to get to that last hill 17:30 so I could walk if if I needed to. I planned to drink and eat something at every aid station I came across to stay fueled and hydrated.

I wasn’t going for any specific time for this race. My main goal was to simply finish.

Before the race

This will briefly cover the logistics so if you aren’t interested please skip to the next section. As soon as the “tour” page opened on the race website I booked a hotel and a bus from Shinjuku. The single rooms in the hotels sold out very quickly (within an hour or so of the site opening) so I booked a shared room.

On April 20th I took the bus from near Shinjuku Station and was taken to a meeting spot at Fuji Q Highland. We were then taken by shuttle bus to our individual hotels.

I ended up sharing a room with two other guys (both of whom were relieved that I could speak Japanese). Dinner was good and we turned in at about 19:00 with the knowledge that we’d be up at 01:30 to get ready and have a quick breakfast before the bus picked us up to take us to the race. I didn’t really sleep at all. I more or less just closed my eyes at 19:00 then waited until my alarm at 01:30.

All of the hotel and bus arrangements were part of the tour I booked. It was a good move to do this.

Report structure

This whole race was a 15 hour effort. I lived a lot in those 15 hours and there’s a lot to get through so I’ll try to keep it brief. During this race (at aid station breaks) I’d occasionally snap a picture and upload it to Twitter with a brief caption. This helped me to keep track of what happened and when it happened.

I’m putting this report together using Tweets, photo metadata, and memory. I won’t go through this by aid station or checkpoint. I’ll just describe it by the main landmarks and occurrences within the race.

富士北麓公園 (Fuji Hokuroku Park)

I arrived at Fuji Hokuroku Park at around 3am. I had one hour to drop off my gear in a hall, grab a coffee and take a picture at a ‘photo booth’ area. When I passed my camera to the staff I stood in front of the event sign and did a fighting stance to get a ‘serious’ picture before the run. I got an unexpectedly loud reaction from a few people watching me get my picture taken, which really cracked me up.

I made my way over to to the start line with about 20 minutes to spare. I was very close to the front of the starting block (right behind the guys doing the “Sparta” 120 km). Right before the race started Ultra Runner Myaco gave a speech (she was running the 62 km division of this race and entered the Mt. Fuji 100 (a 100 mile race in the area) the following week).

I strapped my headlight on and was ready to run into the dark at 4:00 sharp. Go time.

Fighting stance, coffee, Myaco, and the runners at the start line.

First lake : 山中湖 (Yamanakako)

The race started out in total darkness at 4:00. Some people had headlights some didn’t. I was glad I brought a headlight because the ground at the very beginning was a bit bumpy and I didn’t want to fall, get hurt, and get a DNF before the race even started.

There was very little to see at this point of the race other than the light reflected off the other runners gear and the occasional deer in the forest wondering what we were all doing at this hour.

The sun started coming up as we were running and by the time I got to Yamanakako at 05:00 there was no need for the headlight. I switched out my headlight for my hat the first chance I got.

Dawn at Yamanakako.

As the sun came up there was a very clear view of Mt Fuji and the cherry blossoms still looked stunning. I was stopping at every aid station on the way (just as planned) and I ended up passing Yamanakako quite quickly. Yamanakako was probably one of the more pleasant lakes to run around.

First official race photo, aid station leaving the area, and a dawn cherry blossom.

First marathon. The road to 河口湖 (Kawaguchiko)

One thing I noted before I started the race was that to go from the start to Kawaguchiko it was about 50 km. We would be at the ultramarathon distance already having only seen one of the lakes. At the 24 km mark I was already leaving Yamanakako, which meant I had a lot of countryside to run through before I got to the next lake.

Passing through the countryside was not an unpleasant experience at all. I quite enjoyed running through the farms, tulip fields, and forest areas. The aid stations around here were also very nice, but a particular conversation loop started around here. That conversation loop was surrounding my Japanese ability and the fact that I quite enjoy 梅干し (umeboshi : pickled plums), especially when I am racing (they are sour and salty and are perfect for replenishing electrolytes). “Oh! You can speak Japanese very well. Oh! You can eat umeboshi!”

It was around one of these aid stations that I started talking to another runner (S-San) who told me he used to live in the United States. We ended up running together (on again off again) for the rest of the ultra. He was really good company. He also found it amusing that people kept asking me the same questions over and over again. “It’s like if I was in the states and every person asked me if I could eat blue cheese.”

Farms, forests, fruit (aid station) and a park.

Before exiting this section of the ultramarathon there was a very large hill to climb up. I passed this section of the course already on the way down to Yamanakako so I expected the hill on the way back. What I didn’t expect however was how steep the hill would be on the way to Kawaguchiko area. I made frequent stops on the way up the hill to bring my heart rate back down but once I got to the top of the hill my weight largely carried me down towards the next lake.

As I was running I noticed that if I could keep going relatively quickly I could complete my first marathon in under 4 hours. For about 2 km of this downhill segment I was running at 4:39/km then 4:36/km until I cleared a cone/checkpoint showing I passed the full marathon point. I cleared it in just under 4 hours, snapped a quick picture, then carried on to Kawaguichiko.

The hill, a photo of my watch at the full marathon point, and my location on the elevation plot.

North of 河口湖 (Kawaguchiko) and 西湖 (Saiko)

After the big downhill segment things started leveling out a bit more. I lost my new friend S-San on the downhill segment (though I would meet up with him again a bit later) so I was going to be on my own for a while.

My quads were burning at this point. That wasn’t a good sign (especially considering I wasn’t even half way done yet), but I wasn’t going to let a bit of muscle fatigue stop me. This was expected.

When I got to the next aid station I ran into one of the guys I shared the hotel with the previous evening. He is a very experienced ultra runner (he’s 61 and ran another 100k the previous weekend). I told him about my legs being a bit sore and he advised me to drink some vinegar when I saw it. I managed to find some at the next aid station and it did help (though I’m not sure whether it was the placebo effect or not). I’ll take what I could get. My legs weren’t perfect but I was still in the game.

(I was also happy to note that at this stage the aid stations started putting buckets of water out for people to cool down. Scooping cold water onto my head became a pretty regular occurrence from this point on).

Arrival at Kawaguchiko, water bucket, and official race photo.

The Kawaguchiko area is the lowest, flattest part of the run so it was pretty easy going for the most part. The views were stunning, there were blossom trees out of colors I’ve never seen before, and I managed to get to the third checkpoint (56 km) at just after 09:30. I hadn’t been looking at the checkpoints up to this point because I was making good time (cutoff for this one was at 11:10).

It was at this point that S-San caught up to me again and told me that he would be walking the next section and advised me to do so as well. He told me that he ran the Mt Fuji Marathon a while ago which ran through this section and that there was a very steep hill coming up. A bit of an uphill walk sounded good to me so we walked the next part up to the next lake (Saiko).

Kawaguchiko, blossom tree, the third checkpoint, and the steep section on the elevation plot.

After the hill there was a flat section then we were at pretty much the half way point. Saiko (as expected) was beautiful. There were lots of blossom trees out, but unfortunately Mt Fuji was shrouded with cloud. If you take a look at a Japanese 1000 yen note, the picture of Mt Fuji is the view you can see on a clear day from this lake. Although it would have been nice to see, I wasn’t here just for the views and needed to keep running to the next lake.

Saiko, the 60k point, and a really nice official photo

Lake Four: 精進湖 (Shojiko)

After leaving Shojiko the path narrowed a bit and we headed towards the fourth lake, Shojiko. It was around this point that I started to see a greater density of runners doing the three lake (62 km) course. They had skipped Yamanakako and were just doing Kawaguchiko, Saiko, and Shojiko.

I ended up passing one of my parkrun friends who was doing the 62 km course. He was heading away from Shojiko (meaning he had completed the loop) as I was headed towards it. The path was getting a bit narrow here so it was a bit uncomfortable as a two way road but we made it work.

Shojiko is the smallest lake and there was a lot of turnover when crossing the roads. Some people were beginning the loop, some were ending the loop, and people were moving at different speeds, with the 62 km people being quite casual going into and out of the loop, and the 118 km people ending the loop being the real contenders charging towards the finish line. (I didn’t realize how far they had run at this point).

Once I got about half way around Shojiko I passed the point where I was entering personal best territory. The 70 km aid station gave us a fantastic view of Mt Fuji (that cleared up a bit right on time) and was very picturesque.

Shojiko and a picture of me at the 70km point.

The remainder of the Shojiko loop was fine but after completing that loop the course deviated sending the people on the 118 km course towards the final lake and everyone else back towards the finish line. It started getting pretty hard from here.

Final Lake: 本栖湖 (Motosuko)

To get to Motosuko we needed to go down a pretty disorienting section that just seemed to be going down the whole way. It wasn’t a comfortable downhill section either. I saw a sign for 青木ヶ原樹海 (Aokigahara jukai), which some of my readers may recognized as the ‘cursed’ ‘suicide forest.’

I stopped at an aid station on the way to the lake and found a deer skull on a rock. I’m not sure why it was there but it was a bit freaky. That odd feeling was dispelled when I was asked at that aid station if I could eat pickled plums again (as I was eating a pickled plum). S-San was with me and was laughing at the situation.

At one point before getting to the lake we needed to cross under a road using a subway tunnel. This was actually one of the most uncomfortable downhill sections I came across in the race (and it wasn’t any more comfortable on the way back).

We passed an aid station that would serve as the first and last aid station of Motosuko and one woman observed me eat a pickeled plum and loudly whispered to another volunteer, “That foreigner can eat umeboshi.” Whatever…it was time to keep running.

Dear skull, Motosuko and official race pic (with S-San in the background)

At about the 80 km point things started getting kind of bad. The fatigue started catching up to me. My legs had been feeling sore for a long time but my chest was now the problem. I couldn’t run for too long without feeling like I’d been punched in the sternum. S-San was feeling very similar so we ended up walking up the inclines and encouraging each other to run the declines and where we could stomach it on the flat areas. We did a lot of picking landmarks like, “We’ll run from that cone to the next aid station.”

We passed a guy at one of the aid stations who was wrapped in a space blanket and another dude that just that just walked up to the staff and said, “I’m retiring” and sat down. This was a pretty low point of the race and in a section where I got a bit further ahead of S-San I will admit to taking my frustrations out on the lake by yelling, “F this lake,” several times at the top of my lungs.

Finishing the Motosuko section had us turning our backs on the lake at the 86 km mark. There was still 32 km to go. Things were slowing down and checkpoints started to become a concern. It was important to keep moving.

Race against the checkpoints

The next checkpoint as an 90.1 km. Those 4 km between leaving Motosuko and arriving at the checkpoint seemed much longer than they actually were. We were doing a lot of running followed by power walking at this point but we managed to get to the 5th checkpoint (90.1 km) about an hour early.

At the 5th checkpoint I dumped a lot of cold water on myself, drank a lot of coke, and then set off again at a run/walk pace towards the 6th checkpoint at 98.7 km.

After leaving the 5th checkpoint we started going up that ramp through the Aokigahara area again. The stretch of road just seemed to keep going into the distance to the point where people were too small to see. I knew I’d need to run this road, so this produced some more cursing from me, but thankfully 100 km was starting to look realistic.

I stopped at a checkpoint for a bowl of hōtō udon (a kind of noodles that are famous in the area), then managed to drag myself (again, walking and running) to the next checkpoint at 98.7 km. (By this point I was back at Saiko). When I check the pictures after it looks like it took an hour and 20 minutes to go 8.6 km. That would be a pathetic pace of me under normal circumstances but by this point it was survival mode. 19.3 Km to go.

Checkpoint 5, noodles, the road stretching into the distance and checkpoint 6.

The FINAL checkpoint closed at 18:00. My legs were still holding up but fatigue was really taking over my chest. If I ran for too long I felt like I was going to pass out. S-San was with me at the 6th checkpoint and I told him that I would need to go at my own pace moving forward. I had 3 hours and 15 minutes left before the race cutoff and I was confident I could get to the 110.0 km checkpoint even if all I did was power walking so we parted ways at that point with me just trying to put one foot in front of the other until the finish line. (I didn’t only power walk of course. I continued to run/walk for the duration).

My official time to cross the 100 km mark (according to my chip) was 11:42:49 but my watch had me at 11:58:11. Crossing the 100 km point was a big goal for me. Even if I passed out then and there I would have been somewhat satisfied to know that I got to the 100 km mark. But instead of passing out then and this gave me a boost to my energy and confidence. A downhill section followed by a flat section was coming up before the final checkpoint so I was feeling like I was in the clear. At this point I stopped using aid stations and just decided to power through to the end.

100km! And my position on the elevation plot.

I hit 110 km at 17:25. This was right at the bottom of the hill I knew was going to be a problem. I could see the hill stretching off into the distance and it was getting dark. I had just over an hour and a half to do the last 8 km but I knew that this would be the roughest hill on the course. I stopped taking pictures (it was getting dark anyway) and just locked in on the finish line.

The final hill and finish

I was walking for the most part but at the bottom of the final large hill there was a group of guys shouting “ファイト！” (Faito! : Fight!) over and over again at the runners. (This is a common Japanese cheer). One of the guys hit his friend on the shoulder, pointed at me and started shouting at me with, “ファイター！頑張って！” (Fighter! Ganbatte! : Fighter! Do your best!). When I took that picture first thing in the morning, these guys were the ones that made the commotion when I pulled that fighting stance. I gave them an 押忍! (OSU!) as I went past and they all started shouting OSU back at me. This really was great fuel to keep me going on the final stretch.

It was getting darker and darker. It also started raining. The signs leading up to Fuji Hokuroku Park stopped making sense because I seem to recall seeing the same “X km to go” sign multiple times. I could hear the commotion of the finish line in the distance but I still couldn’t see anything.

I knew that the final stretch of this run would be downhill so as soon as I noticed the ground starting to look like a decline I started running. For the last 1.5 km of the run my speed dramatically increased. I went from power walking to the closest approximation of a sprint I could do.

I passed a ton of people a I ran into Fuji Hokuroku Park and after I ran over a particular sensor on the ground I heard the announcer shout my name and say, “Welcome back!” There was a big archway at the finish line which I charged through, passing through a ribbon held by some staff. It was at that point that I let myself slow down and staggered over to a staff member who put a medal around my neck. I’d done it. (I didn’t realize how shell shocked I looked until I saw the race pictures after).

FINISH!

After the race

After the race I could not function properly. I went to the hall to pick up my bag immediately. I picked up my t-shirt then went to the hall to get changed but I needed to sit on the ground to get changed and any time someone spoke to me I was slurring my words. S-San found me as I was collecting my stuff. I believe he came in a little while after I did. (I’m really happy to know he finished as well).

I didn’t hang around at all after the event. I simply got my stuff and got on the bus. I’ll spare you the details of how I got home but I pretty much got home, had a bath, then lapsed into a coma. The next day I took a lot of naps and was pretty much useless. I only managed to walk about 700 steps that day.

Race results

To give a brief breakdown of the results, overall 4,518 people entered the race (4,070 showed up on the date so the attendance rate was 90.1%). The overall completion rate was 73.7% (2,998/4,070). This is across all distances and divisions.

My division was the 118 km mens division. 732 entered, 662 ran. The completion rate of my division was 57.1% (378/662).

I came in 298th place out of 378. I would have been satisfied with last place to be honest. As long as I didn’t DNF I was happy.

My race certificate, medal, and basic Garmin data can be found below:

Also, according to my watch, on the day of the ultramarathon I did 123,792 steps.

Final thoughts

This race was pretty much the hardest feat of endurance I’ve ever done. I pushed myself to the edge of the endurance I had on the day and managed to achieve my audacious goal.

That gap between 100 km and 118 km was pretty large. If my goal was 100 km I think my perspective on the race would have totally changed. I’m very happy that I did the 118 km division because it would have felt unfinished if I hadn’t completed all five of the lakes.

It took a long time to heal after doing this run. I could barely walk for the week following the run but still managed to get back to my minimum 10,000 steps a day pretty soon after. I ran my first 5k a week after the race and felt like my thighs were full of broken glass.

I still had some lingering muscle stiffness even several weeks after the race but it almost felt like a new level has ‘unlocked’ within me. My muscular structure seems more stable and psychologically, I know that I’m able to break 100 km and keep going.

For a while after the race, mentally, I was still in the mountains for some time. It’s a bit of a strange feeling to describe but I just felt like it was almost my duty to keep moving and I want to get back out there and do more.

Though I haven’t decided what my next challenge will be yet, I’m looking forward to getting back out there and trying something like this again.

Thank you!

If you made it this far, thank you very much for reading. Reliving this experience as an after action report was a great way for me to let the whole experience sink in.

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