A 16-week 100-mile century training plan
For riders already comfortable on two- to three-hour rides who want to go the full 160 km. Four sessions a week, a long ride that reaches five and a half hours, two easier weeks to absorb the work, and a lot about eating, because on a ride this long, food is the thing that goes wrong.
Who this plan is for
A century, 100 miles or 160 km, is the distance where riding stops being about fitness alone. You’re looking at seven to nine hours out including stops, which means comfort, pacing and food matter as much as your legs.
It assumes you’re already riding three or four times a week and can do two to three hours without it ruining your weekend. If your long ride is currently an hour and a half, do the 12-week 100 km sportive plan first. If you’ve done a few 100 km events, you could start at week five.
If you have a health condition, a history of heart or joint problems, or get pain on the bike that isn’t ordinary muscle soreness, see a doctor before you start. This is general guidance, not medical advice, and the app that personalises it isn’t a medical service.
What the sixteen weeks look like
Sixteen weeks in five blocks. Base (weeks one to four) grows the long ride to just over three hours at an easy pace. An easier week follows, then build (weeks six to nine) adds hills, steady riding and, from week eight, a shorter ride the day after the long one so you learn to ride on tired legs. A second easier week, then peak (weeks eleven to thirteen), where the long ride reaches five and a half hours, roughly 120 to 130 km. Weeks fourteen to sixteen wind down: a shorter long ride, a proper taper, then the century.
Four sessions a week: one long, one with hills, one with steady stretches, and a fourth that starts as an easy ride or a strength session and, from week eight, becomes the shorter ride the day after the long one. The long ride grows by fifteen minutes a week in base and build and by thirty in the peak weeks, when the rest of the week gets easier to compensate. The two easier weeks aren’t optional: the fitness from a big block only shows up once you’ve rested.
| Weeks | Focus | Long ride grows to | How it should feel |
|---|---|---|---|
| 1–4 | Base: four rides, all easy bar a few hills | 2 h 30 → 3 h 15 | Easy. Chatting pace, even on the hills. |
| 5 | Easier week to absorb the base | 2 h 15 | Fresh by the end of the week. |
| 6–9 | Build: hills, steady riding, and a back-to-back weekend from week 8 | 3 h 30 → 4 h 15 | Purposeful midweek, easy at the weekend. Sunday is on tired legs. |
| 10 | Easier week to absorb the build | 3 h | Fresh again. Resist adding things. |
| 11–13 | Peak: the three longest rides | 4 h 30 → 5 h 30 (roughly 120 to 130 km) | Long, steady, unhurried. A full rehearsal of eating, stops and kit. |
| 14 | Wind down | 4 h | Easy and familiar. |
| 15 | Taper | 2 h 30 | Shorter than feels right. That’s the point. |
| 16 | Taper and the century | The 160 km | Two short spins, two days off, then the day. |
Tuesday: an hour easy with whatever hills your roads have. Wednesday: 45 minutes easy, or a strength session. Thursday: an hour and a quarter easy. Saturday: two and a half hours easy, eating every 30 to 40 minutes from the first hour, because that habit is the plan. Three rest days. Week two adds fifteen minutes to Saturday and nothing else.
A sample week
Week twelve, in the peak. Sunday is the back-to-back ride: shorter, easy, and the one that teaches you the most about how the second half of a century will feel.
| Day | Session | How long | How it should feel |
|---|---|---|---|
| Monday | Rest | — | Fully off. Eat well. |
| Tuesday | Steady: 3 × 10 min | 1 h 15 | The steady bits at the pace you’ll ride the century: short sentences, not chat. Easy between. |
| Wednesday | Rest, or strength off the bike | 0–30 min | Twenty minutes of squats, lunges and planks and a stretch, if you fancy it. |
| Thursday | Hills: 5 × 5 min climbing | 1 h 30 | Climbs at an effort you could hold for fifteen minutes; roll down easy between each. |
| Friday | Rest | — | Prep the bike, the food and the route. |
| Saturday | Long ride | 5 h | Easy throughout, roughly 110 to 120 km. Eat every 30 minutes, drink every 15, stop when you need to. |
| Sunday | Easy ride on tired legs | 1 h 30 | Flat and gentle. The legs complain for twenty minutes and then settle. |
How to adjust it when life happens
Missed a week? Resume at the missed week, not the next one, and let the plan slide if the date allows. If it doesn’t, protect the long rides and the taper and let the midweek sessions go. A longest ride of four and a half hours is still enough for a century if you pace it and eat.
Feeling wiped? The signs of doing too much are subtle: sleep getting worse, a short temper, easy rides feeling hard. Bring the easier week forward. Keep each week’s riding time within about ten to fifteen per cent of the last.
Ill? Rest until it’s gone, then restart with an easy ride. For a ride this long, arriving healthy matters more than any session you missed.
Weather? Shorten rather than skip, swap days freely, and never ride the long one in ice or a storm. A long day on an indoor trainer isn’t fun, but split in two it counts.
The Etapa app builds a personal version of this from your event date, the days you can ride and your recent riding (it reads Strava if you connect it). Sessions land in your calendar, and if you miss one it reshuffles rather than stacks. A weekly check-in asks how you’re feeling and adjusts the next week to match. And the coach is there for the questions that come up at hour four.
Kit, food and the basics
For the century, add a second bottle, a saddle bag you’ve actually opened (tube, levers, pump, multi-tool), chamois cream if you don’t already use it, and a look at your position if your neck, hands or knees complain after three hours. The app can do a first pass at your bike fit from a couple of photos.
Food is the section to read twice. On a seven-hour day you’ll burn far more than you can eat, so the aim is to keep topping up, not to keep up: something every 30 minutes from the first hour, a mix of real food early (sandwiches, flapjack, bananas) and easier things later (jelly sweets, gels if you like them), and a drink every fifteen minutes or so. Use every long ride to practise, and never try something new on the day. More in our guides to beginner cycling gear and eating on the bike.
The week before and the day itself
Weeks fifteen and sixteen are the taper. Week fifteen keeps the rhythm with everything shorter; week sixteen is 45 minutes easy on Tuesday, 30 on Thursday, then rest. Eat a bit more carbohydrate than usual in the final two days (pasta, rice, bread, potatoes), sleep, and lay everything out the night before.
On the day: breakfast two to three hours before, then start easy. Really easy. The first 50 km should feel like you’re holding back, because you are; that’s the energy you’ll want at 130 km. Eat from the first half hour, stop at every feed station, and stretch your back and neck when you do. Around three-quarters of the way through, most people hit a low patch. That’s normal: eat something and it passes. The last 20 km is usually the best bit.
How long does a 100-mile ride take?
For a first century, plan on seven to nine hours including stops. At a steady 22 km/h that’s about seven and a quarter hours of riding, plus food stops and the odd photo. Faster is possible; comfortable is the goal.
Do I need to ride 100 miles in training?
No. A longest ride of five to five and a half hours, around 120 to 130 km, is plenty. The taper, the feed stops and the company on the day cover the rest. Riding the full distance in training tends to leave you tired for the event rather than ready for it.
How much should I eat on a century ride?
More than feels natural. Aim for something every 30 minutes from the first hour, with real food early and easier things like jelly sweets and gels later, and drink every fifteen minutes. Everyone’s stomach is different, so use the long rides to find what works for you and don’t try anything new on the day.
What if I can only train three days a week?
Keep the long ride, the hills session and the steady session, and drop the easy fourth ride. You’ll miss some of the back-to-back weekends, so make sure the long rides still happen and consider adding two weeks to the plan if your date allows. Three good sessions a week will get you round.
Do I need a heart-rate monitor or a power meter?
Neither is necessary. Every session here is described by feel, and how you feel is what matters over eight hours. If you already own one, a heart-rate monitor is useful for spotting when you’re more tired than you think; a power meter is a nice-to-have for later.
Get to 100 miles with a plan that knows your week
Etapa builds a personal century plan from your event date and the days you can ride, checks in with you every week, and moves sessions around when life does.
Free to download. 7-day free trial on every plan.