The Quebrantahuesos starts in Sabiñánigo — a quiet Aragonese town that sits in the shadow of the Spanish Pyrenees — and within 50 kilometres, you are climbing into the mountains that form the border with France. 200km, 3,500m of climbing, three major cols, a border crossing and return, and the name of a bird that breaks bones by dropping them from great height. The Bearded Vulture. The Bonebreaker. It is, without much argument, Spain's hardest and most prestigious one-day cycling event, and the 8,000 riders who win the lottery each year know exactly what they are signing up for.
What makes the Quebrantahuesos deceptive is the profile. It does not look as savage as La Marmotte or the Ötztaler. The average gradients are lower, the total elevation is lower, and there is no Alpe d'Huez or Timmelsjoch waiting at the end. Riders look at the numbers and assume it will be a long but manageable day. Then they hit the Portalet — 27 kilometres of gradual climbing that drains you not through steepness but through duration — and realise the Quebrantahuesos fights differently. It wears you down. And then, after 170 kilometres of wearing you down, it throws the Marie Blanque at you — short, steep, narrow, and vicious.
This guide is the framework we use with riders inside Not Done Yet who are preparing for the Quebrantahuesos and other Pyrenean events. The plan is grounded in real finisher data, the pacing strategy is specific to the three-col structure and the cross-border logistics, and the fuelling plan accounts for the Spanish June heat that makes this event different from anything in the Alps.
What Makes Quebrantahuesos Different
Most gran fondos and sportives sit neatly inside one country, one mountain range, one set of weather conditions. The Quebrantahuesos crosses an international border, climbs through two distinct sides of the Pyrenees, and puts you through temperature swings that can span 25 degrees in a single day.
The long-slow-then-steep structure. The Portalet and Somport are both long, both gradual, and both deceptively draining. The Portalet — 27km at 3.9% average from the Spanish side — is the kind of climb that does not hurt on any individual kilometre but accumulates into something significant over 90+ minutes of steady effort. The Somport at 13km and 3.6% is similar. Neither will break you if you respect them. Both will hollow you out if you ride them too hard, and then Marie Blanque — 9.4km at 7.7% average with ramps above 10% — finishes the job.
The cross-border logistics. You leave Spain via the Portalet, descend into the Vallée d'Ossau in France, cross French territory before climbing the Marie Blanque, and then return through the Somport. This sounds like a footnote but it affects feed-zone planning, phone signal for anyone relying on live tracking, and — if conditions turn — the weather patterns on the French side can be markedly different from the Spanish side. The French Pyrenees tend to be wetter and cooler. Riders who dress for Spanish heat sometimes arrive at the Marie Blanque in French cloud and drizzle.
The heat. Late June in the Aragonese valleys means 30°C or more at valley level. The climbs provide altitude relief — the Portalet summit sits above 1,700m and the Somport tops out at 1,632m — but the descents and valley sections between cols bring you back into full sun. Dehydration and heat-related power loss are as real a threat here as the gradients. The heat training guide covers the adaptation protocols. If you are not acclimatised to riding in 30°C heat for 7-9 hours, that is a gap in your preparation.
The lottery and the field. 8,000+ riders start, drawn by ballot from a significantly larger pool of applicants. If you have a place, you may not get another one next year. The field skews serious — this is not a participation-medal event. The pace on the rolling sections between cols can be surprisingly high, with groups forming and the drafting effect pulling riders above their sustainable power. Riding alone or in a small group at your own pace is almost always the better strategy.
Fitness Benchmarks: Where Do You Need to Be?
Your power-to-weight ratio determines how the day feels. Unlike pure climbing events, the Quebrantahuesos also rewards riders who can sustain power on rolling terrain — a significant chunk of the 200km sits between 2% and 5% gradient where aerodynamic drag still matters.
| Target | W/kg (sustained) | Approximate Finish Time | Notes | |--------|-------------------|------------------------|-------| | Competitive | 3.6+ W/kg | ~6:30-7:00 | Strong climber, efficient in groups, dialled nutrition | | Strong ride | 3.2-3.5 W/kg | ~7:00-7:30 | Solid amateur, consistent pacing, no major errors | | Comfortable finish | 2.8-3.1 W/kg | ~7:30-8:30 | Good fitness, disciplined pacing, full use of feed zones | | Completion | 2.4-2.7 W/kg | ~8:30-9:30+ | Time-limit target, conservative throughout, eat everything |
Two caveats matter here. First, these W/kg numbers are sustained output across 7-9 hours, not your fresh 20-minute test. Your FTP might read 3.4 W/kg on the turbo trainer, but after five hours of riding in 30°C heat your real output on the Marie Blanque will be closer to 85-90% of that. The FTP zones tool will frame your training zones, and the Climbing Time Estimator will translate your W/kg into projected ascent times for each col.
Second, the rolling terrain between cols makes this event more forgiving of slightly lower W/kg than a pure climbing event like the Marmotte — but only if you can ride in a group. A 3.0 W/kg rider sitting in a peloton on the valley roads uses 15-20% less power than the same rider alone. If you lose the group on the Portalet and ride the valley sections solo, add 20-30 minutes to your finish time.
The 16-Week Training Structure
The plan follows a base-build-taper progression. It assumes you are already riding 8-10 hours per week with some climbing experience. If you are starting from a lower base, add 4-6 weeks of steady aerobic riding before week one.
Phase 1: Base (Weeks 1-6)
Volume: 8-11 hours/week. Four to five rides. 80% in Zone 2.
The Quebrantahuesos is a 200km day. That means the aerobic base is everything — the sustained power you can hold at conversational pace for hour after hour is what carries you from Sabiñánigo to the base of the Marie Blanque with anything left. Dan Lorang's philosophy at Red Bull-Bora-Hansgrohe is that the aerobic base underpins everything above it, and amateur riders who skip this phase to chase threshold numbers arrive at long events with speed but no durability.
Weekly structure:
- 3-4 Zone 2 rides (1-2 hours midweek, longer on weekends)
- 1 quality session: sweet spot, 2x20 minutes at 88-93% FTP
- 1 long ride building from 3 hours to 4.5 hours by week 6, with 500-1,000m of climbing
- 1-2 gym sessions: single-leg press, lunges, core work, hip stability — support the climbing posture and the hours in the saddle without loading the spine
Key metric: By week 6, a 4.5-hour ride with 1,000m of climbing should feel controlled, not heroic. If it feels like a peak effort, you need more time in this phase before progressing.
Heat adaptation note: If you are training through spring in Northern Europe or any climate where 30°C riding is not routine, begin introducing heat exposure in the base phase. One indoor session per week without a fan, 60-75 minutes at Zone 2, starts the plasma volume and sweat-rate adaptations you will need in June. This is not optional for the Quebrantahuesos. The valleys are hot.
Phase 2: Build (Weeks 7-12)
Volume: 10-14 hours/week. The terrain-specific work begins.
This is where the training starts to look like the event. Two quality sessions per week, long rides building to 5-6 hours with sustained climbing, and at least two weekends where you stack back-to-back riding days.
Weekly structure:
- 2 quality sessions (see below)
- 2-3 Zone 2 rides
- 1 long ride building to 5-6 hours with 1,500-2,000m of climbing
- 1 gym session (maintain strength, don't build — the climbing volume does the leg work now)
Quality session 1 — sustained climbing intervals: 3x15 minutes at 90-95% FTP on a gradient, progressing to 2x25 minutes by week 11. The Portalet demands 90+ minutes of sustained output — you need to train the metabolic and muscular capacity for that, and shorter intervals that build to longer ones are the path. If you lack gradients, overgeared flat intervals at 55-65 RPM simulate the muscular cost.
Quality session 2 — VO2max intervals: 5x4 minutes at 106-115% FTP with 4 minutes recovery. Professor Seiler's research is unambiguous — two intensity sessions per week in a polarised framework, with the remaining volume properly easy. The VO2max work raises the aerobic ceiling so your threshold efforts feel less costly across a full day.
The stacked weekend: At least twice during the build phase, ride a 4-5 hour Saturday with 1,500m+ climbing followed by a 3-4 hour Sunday with 1,000m+ climbing. This teaches the body to ride hard on tired legs — and that is exactly what Marie Blanque asks. The riders who handle the final col well are the riders who have practised arriving at a steep climb already fatigued and still making controlled power.
Simulating the Portalet: If you have a long, gradual climb available — 20+ minutes at 3-5% — ride it at 70-75% FTP and focus on cadence consistency. If you do not have a suitable climb, ride a flat road in Zone 2 for 90 minutes at a fixed cadence of 80-85 RPM without surges. The Portalet is not steep enough to hurt — but it is long enough to drain you if your effort is even slightly above sustainable pace.
Phase 3: Taper (Weeks 13-16)
Weeks 13-14: Volume holds at 10-12 hours. One final stacked weekend, ideally with a long, steady climb followed the next day by a short, steep effort. This is the closest simulation of the Portalet-to-Marie-Blanque demand.
Weeks 15-16: Volume drops 30-40% in week 15, 50% in week 16. Keep short, sharp efforts in the mix — 3x5 minutes at threshold, 4x90 seconds at VO2max — to keep the legs responsive. Cut the gym work entirely. Sleep more. Eat well. Trust the fitness you built.
The mistake most riders make in the final fortnight is adding volume because they are nervous. The taper sheds fatigue without losing fitness. A properly rested rider gains 5-10 watts on race day compared to a rider who trained hard until Wednesday of race week. You will feel that difference on the Marie Blanque.
Climb-by-Climb Pacing Strategy
Pacing the Quebrantahuesos is a three-act problem — but the acts are not equal. The Portalet takes the longest, the Somport is the most straightforward, and the Marie Blanque is the most demanding per kilometre. Getting the effort distribution right across these three — and across the 200km total distance — is what separates riders who finish strong from riders who survive.
Col du Portalet (27km, 3.9% average — Spanish side)
Target effort: 70-75% FTP. The Portalet is the longest climb of the day and the one most riders get wrong. The gradient is mild — 3.9% average — and the legs feel fresh in the first 30km of the event. Every instinct says push. Ignore it.
27 kilometres at 3.9% takes 75-100 minutes depending on fitness. That is a significant effort by duration alone, even at a gentle gradient. Your VAM on the Portalet should be conservative — 600-700m/hour for most riders, well below your maximum sustainable climbing speed. The road winds through the Tena Valley, the scenery is spectacular, and there is absolutely no reason to spend matches here that you will need 150km later on the Marie Blanque.
The summit sits at 1,794m. If the weather is clear, the descent into France through the Vallée d'Ossau is fast and beautiful. If cloud has settled, it can be cool and damp. Have arm warmers accessible.
Col du Somport (13km, 3.6% average)
Target effort: 75-80% FTP. The Somport is the most straightforward of the three cols — a steady, gradual climb without dramatic gradient changes. At 3.6% average across 13km, it takes 40-55 minutes for most riders and should not feel like a significant effort if the Portalet was paced correctly.
The Somport summit sits at 1,632m and marks the return crossing into Spain. Eat on the climb. Drink on the climb. This is a working section of the day, not a highlight — and that is exactly how you should ride it. The riders who make the Somport feel easy are the riders who will have something left for the Marie Blanque.
Marie Blanque (9.4km, 7.7% average)
Target effort: 85-92% of whatever you have left. This is the col that gives the Quebrantahuesos its reputation. After 170+ km of riding, after the long attrition of the Portalet and the steady grind of the Somport, the Marie Blanque arrives with a completely different character — short, steep, narrow, and relentless. Ramps above 10% appear in the second half when your legs are at their worst.
The Marie Blanque is the Quebrantahuesos equivalent of Alpe d'Huez at the Marmotte. It is where the day reveals itself. Riders who paced the Portalet conservatively, fuelled through the Somport, and used the valley sections to recover arrive at the base of the Marie Blanque with cards to play. Riders who went too hard too early arrive empty.
Pace the first 3km conservatively — the gradient is above 7% from the start and the temptation to attack immediately is strong. Settle into a sustainable cadence of 65-75 RPM. The steep ramps in the second half are where your gearing and your remaining glycogen stores matter most. If you have trained specifically for steep climbing on tired legs — and the stacked weekend sessions are designed for exactly this — the Marie Blanque is hard but manageable. If you have not, it breaks you. The clue is in the name.
For a broader framework on managing effort distribution on long ascents, the pacing guide for long climbs covers the principles that apply here.
Gearing
The Portalet and Somport are gentle enough that gearing is rarely an issue. You could ride both on an 11-28 cassette without discomfort. The Marie Blanque is a different proposition entirely.
Run a compact crankset (50/34) with a 34-tooth cassette. At 7.7% average with pitches above 10%, after 170+ km of riding, you need a gear that lets you spin at 65-75 RPM without pushing power you no longer have. The maths is straightforward: a 75kg rider (plus 8kg of bike and gear) on a 10% pitch at 34x28 needs roughly 280 watts to hold 75 RPM. At 34x34, that same cadence requires roughly 230 watts. After seven hours in the saddle, those 50 watts are the difference between climbing the Marie Blanque and walking it.
Fit the cassette early in the build phase. Train on the gearing you will race on. The Portalet and Somport will barely touch your largest sprocket — that is fine. The cassette is insurance for the final 9.4km, and you do not buy insurance the day you need it.
Fuelling Strategy
The Quebrantahuesos is a 7-9 hour day in summer heat. A 75kg rider finishing in 8 hours burns somewhere in the region of 4,500-5,500 kcal. The heat increases both caloric expenditure and fluid loss, and the combination of Spanish sun at valley level with altitude exposure on the cols creates a dual stress that makes fuelling harder, not easier.
Target: 80-90g of carbohydrate per hour from kilometre one. Use the fuelling calculator to plan exact quantities against your projected ride time and bodyweight. Do not wait until you feel hungry. Do not wait until the first climb. Start eating in the first 20 minutes and do not stop.
The first two hours are the most important fuelling window. Your gut absorbs carbohydrate most efficiently when you feel best. By hour six, absorption drops and nausea risk rises — especially in heat. The riders who eat aggressively early are the riders who can still eat comfortably on the Marie Blanque. The riders who skipped food because the legs felt good in the valley are the riders cramping at 8% gradient with empty tanks.
Hourly plan:
| Hour | What to Eat | Notes | |------|------------|-------| | 1-2 | Drink mix (40-50g/hr) + 1 gel or bar per hour | Easy to absorb, save solids for feed zones | | 3-4 | Drink mix + real food (rice cakes, banana, energy bar) | Flavour variety prevents nausea in heat | | 5-6 | Gels and drink mix, small amounts frequently | Gut tolerance drops — eat what sits well | | 7+ | Gels and liquid carbs, sips not gulps | Solid food may not stay down this deep |
Hydration. 750-1,000ml per hour in the valley heat, dropping to 500-750ml on the cols where temperatures ease. Sodium matters — 500-1,000mg per litre of fluid — because sweat rates in 30°C+ riding are significantly higher than in spring training conditions. The hydration tool will help you dial intake against bodyweight and expected temperature. If you have not practised drinking a litre per hour during training, your gut will resist it on race day. Train this.
Pre-race. 8-10g of carbohydrate per kg of bodyweight the day before. Breakfast 3-4 hours before the start — 2-3g/kg of carbs, moderate protein, low fibre, low fat. This is the same protocol covered in the 100-mile sportive nutrition plan, and it applies directly.
Train your gut to this volume across at least four long rides in the build phase. The Quebrantahuesos feed zones are well-stocked but the distances between them can stretch 40-50km — carry enough that you are never relying on the next station to rescue you.
Race Day Execution
What to Wear
The temperature range on race day can span 20-25 degrees. Valley sections at 30°C+ demand sun protection, light colours, and ventilation. The Portalet summit at 1,794m and the Somport at 1,632m are significantly cooler — and if cloud, wind, or rain arrives (afternoon thunderstorms in the Pyrenees are common in late June), the descents can be cold. Check the wind chill calculator against the forecast for each col the evening before.
Start in shorts, jersey, and a sun cap or well-ventilated helmet. Pocket a gilet and arm warmers. The gilet goes on before the Portalet summit if conditions look cool for the descent into France. Strip it off in the valley before the next climb. If the forecast shows any chance of thunderstorms, a lightweight packable rain jacket is cheap insurance — descending the Portalet in heavy rain at 60kph without one is a core-temperature problem that can end your day.
Sunscreen. Reapply at feed zones. Seven hours of Spanish sun burns skin that has been trained under cloud cover in northern Europe. This is a performance issue, not a cosmetic one — sunburn accelerates dehydration and thermal strain.
The Heat
Heat is the Quebrantahuesos's hidden col. It does not appear on the profile but it costs watts. At 30°C+, your body diverts blood flow to the skin for cooling, reducing the volume available for working muscles. Heart rate drifts upward at the same power. Perceived effort rises. The riders who manage this well are the riders who started heat acclimatisation in training, who drink proactively, who pour water over their head at every opportunity, and who wear clothing that does not trap heat.
Ice socks — a freezer bag of ice stuffed into a jersey pocket or under the helmet — are surprisingly effective and several feed zones offer ice. Pre-cooling with an iced drink in the 30 minutes before the start is also worth the effort on a hot morning.
Cross-Border Logistics
Your phone will likely switch networks as you cross into France. If you are relying on live tracking, GPS apps, or mobile data for navigation, download offline maps beforehand. The route is well-marked with signage and marshals, but riders who lose the group on the French sections can feel properly isolated for stretches.
Carry your European Health Insurance Card or equivalent. Emergency services operate across the border but having documentation accessible saves time if you need it. Leave photocopied race documents with your support crew.
The Final 30 Kilometres
The return from France through the Somport deposits you back in Spain with roughly 30km remaining — including the Marie Blanque approach and the final valley run back towards the finish. This is where the day is won or lost.
Between the Somport descent and the base of the Marie Blanque, eat everything you can tolerate. A gel with caffeine at the 15km-to-go mark is worth considering if you have trained with caffeine and know your tolerance. Spin easy on any flat sections. Keep heart rate low. Arrive at the base of the Marie Blanque with a full bottle, food in your stomach, and a cadence plan: start at 65-70 RPM and let it drop only when the gradient forces it above 10%.
The Marie Blanque takes 25-45 minutes depending on fitness and fatigue. That is 25-45 minutes between you and the finish line. If you have paced the Portalet conservatively, fuelled through the Somport, managed the heat in the valleys, and used every flat section to recover — you will climb it. Not comfortably. Not easily. But you will climb it with power in your legs and control in your head, and that is what the Quebrantahuesos asks.
The descent off the Marie Blanque and the run back to Sabiñánigo are the final kilometres. The relief of cresting the summit tempts riders to fly down the descent — but the road is narrow and technical. Ride it safely. You did not prepare for 16 weeks to crash on the last descent. The valley road back to the finish is flat and — if you have ridden well — the sweetest 15km of your year.
Frequently Asked Questions
The answers above cover the preparation in detail, but here are the questions we hear most from riders inside Not Done Yet who are targeting the Quebrantahuesos.
Can I train for Quebrantahuesos without mountains? Yes, but you need to be deliberate about it. Indoor trainers with gradient simulation can replicate sustained climbing efforts — a 90-minute Portalet simulation at 70-75% FTP is entirely possible on a smart trainer. Overgeared flat intervals at 55-65 RPM simulate the muscular cost of climbing. For the Marie Blanque specifically, short steep motorway bridges, multi-storey car park ramps, or any short punchy gradient ridden on tired legs is better than nothing. That said, at least two weekends on real mountain terrain during the build phase are strongly recommended. The bike handling on Pyrenean descents, the heat management, and the mental stamina of a 27km climb cannot be replicated indoors.
How does Quebrantahuesos compare to La Marmotte? The total elevation is lower (3,500m vs 5,180m) and the gradients are generally more moderate. But the distance is longer (200km vs 174km), the heat is typically more severe, and the Marie Blanque — while shorter than Alpe d'Huez — is steeper on average and arrives later in the day relative to total distance. The Marmotte guide covers a similar training structure. If you have ridden one, the other is within reach with route-specific preparation.
Is the lottery entry worth planning a season around? If you get a place, yes. The Quebrantahuesos is the most oversubscribed gran fondo in Spain and one of the most sought-after in Europe. The field, the organisation, the route, and the atmosphere in Sabiñánigo are all first-rate. Plan your season around it. If you do not get a place, the Raid Pyrénéen covers a longer but equally spectacular Pyrenean challenge that does not require a lottery.
Should I recce the course before race day? If you can visit Sabiñánigo and ride the early kilometres including the start of the Portalet, it removes a layer of uncertainty. Driving the Marie Blanque — seeing the gradient ramps, the narrow road, the hairpins — is particularly valuable. The majority of riders finish without a recce, but those who have ridden the course pace better because they know what to expect at kilometre 170 rather than guessing.
What if I am only targeting a finish? The training framework is the same — cut the intensities. Ride the Portalet at 65-70% FTP instead of 70-75%. Take the Somport at whatever pace keeps your heart rate in Zone 2. Use every feed zone for 5-10 minutes instead of 2-3. Walk the steepest ramps of the Marie Blanque if your legs demand it — there is no shame in it, and plenty of finishers have done exactly that. The Quebrantahuesos is the same event whether you finish in 7 hours or 9 — and every rider who crosses that line in Sabiñánigo has done something that 95% of cyclists never will.