Smile Endurance Relay Marathon in Ebina Undō Koen (スマイル耐久リレーマラソンin海老名運動公園) : 4 Oct 2025
Running is generally quite an individual sport, but there are some events where team work is essential. Relay races are the main events that come to mind, but in Japan 駅伝 (Ekiden) style long distance 襷 (tasuki: sash) relays are more popular.
Last year I had my first opportunity to run a 3 hour relay marathon with some of my beach sprinting friends called the Running Park in Shonan Hiratsuka (3 Hour Relay Marathon). That relay marathon was in mid-September and was VERY hot.
This year I was given the opportunity to run a longer relay (4 hours) under more favorable conditions in October. That event was the Ebina Smile Endurance Relay Marathon.
The course was partially on a track but mostly around the grounds of a sports park.
My beach run friends were entering this one and we were going to split up into 3 teams: An elite team and two teams of regular runners with mixed ability. The two regular teams were just entering for the experience and to have fun but the elite team was aiming to go at it as hard as possible.
And with that background out of the way, on to the race report.
The race!
The week leading up to the race I didn’t really do anything different with my training. I kept to running 10 km a day but made sure to keep the intensity low in the lead up to the run.
I took the train with a couple of friends and got off at 社家 (Shake) station. It’s pronounced “sha ke,” (two words) not “shake” by the way (but I had a laugh with my friends about the station name). We did a light jog (1 km) over to the ground and managed to get some good seats on the with the rest of the members who arrived separately.
We picked up our blue team tasuki (sash) along with our timer chip. In the previous relay I did we wore timer chips on our shoes, but this one had the chip attached to the sash, meaning the sash itself needed to cross the line for a lap to count. There are knots that can be tied in the sash to make it adjustable but I just tied a really secure knot to make sure we wouldn’t lose the chip at any point.
My team had 6 members (4 men, 2 women). We didn’t have much of a battle plan for the relay other than just take it in turns one person at a time and see how it goes at the end. It was decided that I would be the second runner.
At 11 am the race started and we had 4 hours to run as far as we possibly could. The first runner (M-San) ran his loop, and just before he got to the start/finish point I started jogging along, took the tasuki from him, crossed the start line, yelled “押忍 (OSU!),” then essentially sprinted my first loop. As I ran back into the stadium area I took off the tasuki and ran with it in my hands before holding it out so the next runner (O-San) could grab it and sprint off. I completed my first loop at a pace of 3:27 /km.
After O-San there were three other runners. Each loop was taking around 4 minutes (on average) which meant after completing a loop we had roughly a 20 minute break to recover then charge off on the next loop.
Each loop started pretty much exactly the same for me. I’d grab the sash, yell OSU at my team mates as I passed them then navigated the twisty course, jumping over manhole covers in the first part, hitting the turn, then sprinting as hard as I could once I got to the part with no obstacles until I reached the end. This pattern continued up to about the 3 and a half hour point and then we needed to make a decision.
We were all taking it in turns to run one loop at a time so we could sprint the course, but because we were running out of time we needed to figure out how to try to make the best of the remaining time we had by putting out our fastest runners (who were appropriately rested) towards the end. We all agreed between us that at that in the last 30 minutes everyone would run as if it were there last lap and if there was only a little time left either I or O-San would run the last lap. As it happened, I ran, O-San ran, S-San ran, and by the time S-San returned the race clock was ticking over to just past 3:56:00. I was up.
I met S-San a bit before the changeover point, grabbed the tasuki and sprinted as hard as I could for the final lap. A lot of thoughts ran through my head as I was doing this (most of them were about running that fast not being a good idea), but I knew that a lot of people were cheering for me and wanted me to keep going. As I ran back towards the stadium I could see my teammates jumping over fences so they could cheer me on better. I passed several people on the way back including one guy who looked like he had given up on the final lap but he cheered me on as I went past.
As I entered the stadium area EVERYONE was cheering for me. People who were not even on my team were shouting encouragement. As I got to the final stretch I saw the clock and the number started with a 4 meaning I had just missed out on the final lap counting, but I kept going, blew through the finish line, and collapsed in a heap on the grass after. It turned out I’d missed the cutoff by 10 seconds…but even though I didn’t make it, it was a glorious finish and I’m glad I finished the way I did rather than just walking over the finish line.
Results
Of the 3 teams that entered from my beach run friends, the elite team came second overall, team 1 came in 5th, and team 2 (my team) came in 6th. There were 13 teams overall so I was happy to be in the top 50%.
I don’t know how many laps we did exactly but since I ran 10 loops (with the final one not counting) I assume everyone completed a full 8 loops, then 4 team members completed an additional 1 loop each, bringing the total to 52 loops, or 59.8 km of completed loops in 4 hours.
My splits are as follows (note that these are 1 km splits, and not splits for the loops).
I managed to get a new personal best for my 1 km time (3 minutes 20). My Garmin showed that I had new personal bests for 5K and 10K but I did not accept them because of the breaks between the loops. Running a 5K in 17 mins 30 seconds is not the same as running 1 km 5 times with a rest in between and the running time coming to 17 mins 30 seconds.
There are no official results online for this race right now, but if I get them I will update this article.
Final thoughts
I had a lot of fun during this race. We didn’t enter to win. We entered as a team of mixed ability people with the goal of having fun, doing our best, and improving.
Running on a race team is a very different experience than running for yourself. When you run for yourself the speed you run is the speed you run. But when you are on a team, your results impact 5 other people. If you care about what you are doing you don’t want to let your teammates down, which means you are able to dig deeper and find strength you may not be able to find in regular circumstances.
I believe that every time you find a way to push yourself to the next level, your body remembers the what you achieved and sets that as a level you can safely go to.
Maybe there really is something to that “power of friendship” trope.
Thank you very much to all of my teammates who participated on the day. I see most of you every week anyway, but I am looking forward to running with you again soon.
OSU!
Thank you
Thank you very much for reading.
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