How do you train for a 100km race?

I had this question last night at track, and it got me thinking.  The answer I gave was short because my training plan was actually pretty simple.  Once a month, in the lead-up to the race, sign up for an ultra and run it as a training run.  Don't race it, but use it as an opportunity to get in a long run.  By doing this you convince yourself that you will be able to go the distance on race day.  Of course, practice your nutrition and pacing for your given goal (100km) race. 

With those ultras under your belt as a physical and mental base, you don't need to do a lot of 20+ weekly training runs. I find that those, if done too frequently, tend to just grind you down.  Instead, focus on weekly time on feet and mileage.  I count gym time as time on feet and, honestly, in addition to running practice ultras, the other big piece is doing strength training. I do hard/easy alternating weeks in the gym, with up to 5 strength sessions in a hard week.  On the easier gym weeks, you can ramp up the running mileage to make up for the time on feet short-fall, aiming to get 8-10 hours of training in per week.

Aside from the above (ultras as training runs and gym), you just go about your business as normal: do the Monday night runs and track with the club, and lead Sunday runs in the forest, and then run three more times per week totalling six times per week for an average mileage between 40 and 60 miles per week.  My highest mileage week was 62, and I didn't run more than 20km in one go that week.  My longest run overall through the whole training block was a 33 mile run across Dartmoor, in harder than race day conditions.  

Completing my first 100km non-stop took a long time to work up to. I would say it took me 5 years to finally reach my goal: from my first ultra in 2019 when I did part 2 of Race to the Stones (5h 30mins coming in 10th place overall), through my unsuccessful attempt last year in 2024, until this year's concerted effort to get organised and mentally optimistic with the explicit goal of completion.  So, it does take some time, and it's by no means easy.  But if you train right and are smart, you can make it look relatively easy on race day!

Race to the Stones 2024: 100km non-stop

I put my wife Diane right at the top of this blog post because she was the key piece of my ultra puzzle that I set out to solve in my most recent attempt at the Race to the Stones 100km non-stop.

Selfie at Base Camp (50km)

Just to run through the main things that came together (in addition to providing Diane with a detailed set of 5 checkpoints, in addition to the race's 7, where she met me, using the What3Words app and Waze): there was excellent weather, cool and partly cloudy, with significant portions of the day in optimistic sunshine; there was excitement at the start line due to lack of rain, and just the great general vibe you specifically get at this event; pacing at an 11/5 run/walk with low HR throughout (walking uphills); running downhills; the use of poles to maintain rhythm and power up the hills; and finally: eating enough (see me with food in my hands below).

Eatin a banana at base camp

My food situation went well, and I ate enough to get through (as opposed to last year where I crashed in part due to lack of an energy plan).  Base camp supplied vegetarian chilli with rice and garlic bread, vegan lemon meringue pie, and tea.  This was a full reset before heading out into part 2, and I had already set up a base level of calorie consumption that was borderline gluttonous and that had my stomach just a little bit upset.  I ate 8 mini sausage rolls, 5 bananas, half a Kendal's mint bar; six gels; and a litre of tailwind.  There's probably more that I'm forgetting.

On top of the big hill just past Foxhill

The first part of the course is spectacular, with all kinds of varied features.  The second half is simlarly stellar, and all kinds of names ramble by: Hackpen White Horse; Wayland Smithy, etc. But just the fields and rolling terrain alone are enough to keep you going, as the whole course tends to feel very remote.  You feel like you're 'out there' in the wilderness, alternating through the swaying wheat fields and remnants of forest. 

Heading into the night past Foxhill

One of the 'firsts' for the day (aside from finishing my first 100km non-stop) was doing a few hours of ultra-running in the dark.  I had trepidation going in, but was well prepared, and learned from last year to have a good headlamp, and to get your base warm layers on while it's still light.  Last year I was too slow and it was pitch black when I hit Foxhill (45miles).  This year it was a whole other story: a beautiful sunset with full sunshine at Foxhill where I pulled up a chair that Diane got out for me, and donned trousers and rain jacket. This in anticipation of cooling, and rain, and dark, all of which happened in short order (and a lovely cooling ground fog at the finish).

A sample of the ridgeway track

The course is in many places (especially at the end) very uneven.  There's one section 5-10km from the finish that is like a weaving multi-track nightmare rutted ledges that are extremely hard to navigate, especially in the dark.  Another success for the day was having my poles with me which, in addition to giving me that nordic cross-country rhythm, also gave me a lot of stability on these final horrible sections.  

It gets a bit better just before the end of the race which, at night, shows up as an eerie floodlight way off in the distance, with glowing chalk hills and rolling fog just scrolling along at your feet.  As you roll down those hills the excitement builds and you see people you've seen along the course, their faces lighting up, and their feet dancing as the energy levels rise again in anticipation of the finish. 

Ready with headlamp, and base layers (top and bottom)

I ran hard the final two miles, down that last hill, and across the little Avebury boulevard (it's amazing to be back in civilization) with its streetlamps and houses set back from the street, you run out to the cone, which is where in past years they'd take your photo at the standing stone (now we call it Race to the Cone instead), and the marshall tells you you have 2km to go, even though you're almost right beside the finish line, so you run back the way you just came, away from the finish line, hang a left, back across a little remote feeling field (back to that again), and around, and finally you see off in the distance the floodlights looking like a ship anchored offshore in the fog, and it looks like it's 10 miles away.  But by this time I had so much energy I was running an 8 min/mile pace, definitely feeling fast after a 16 hour shift of alternating 11 min/miles, sprinting (it felt like) and chatting to my fellow runners, as we moved across those final three sensor strips, and collected our medals. 

The medal (it says 100km on the ribbon)

I didn't run for the medal, but I do love to get a medal.  I was figuring out 'my why' on the drive up in the morning, when I was having a serious whine to Diane and threatening to only run half because "I don't want to trash my feet". My why was simply to finish 100km all in one go.  I kept it simple and I did it.   My goal was to finish, not to get a time, but I did push, hoping for a PB, which I got.  

To compare what it is like to run 100km over two days versus all in one go (as I discussed with Diane on the way home from Avebury at 2am, keeping the conversation afloat so we could stay awake, staring out at the blinding fog): I think they're both equally hard.  That is my hard-earned conclusion.  The two day 100km is hard because on the mental effort of getting through the night without really sleeping and worrying about the next day's run.  On the non-stop you don't have that, and you aren't as stiff, but you also have significantly fewer hours to make a recovery, which you do to some extent get on the two day.

Strava map shows moving time

The map above shows that I was moving for just under 15 hours, meaning my combined stop time was about 1 hour and 40 minutes.  This was for 7 of the race checkpoints and 5 for Diane's crew points, a total of 12 checkpoints, at each of which I took a few minutes.  Base Camps was 1/2 hour.  The remaining 70 minutes, then, were spread between 11 stops, which I feel is pretty good.  I didn't linger too long, just got a little rest to get the heart rate down, and got the Tailwind and water refills, and ate what I could.  By the second half that was really only gels and Tailwind.  I estimate to have eaten 20 gels total, and to have consumed 2 litres of Tailwind.  For a calorie burn of about 7000 for the day, this in the end is really what got me around (and Diane mixing and handing it to me).  Oh, and two litres of Coke at the RTTS checkpoints as well.  

This year's blister count is 1.  I had only one blister this year due to the dry conditions, of course it was a pinkie toe.  One little part of my body looks like hamburger.  The rest of me just aches, even now, two days later.