Every April, riders sign up for a summer gran fondo and then spend eight weeks doing the same three-hour Sunday loop at the same moderate pace. On event day they finish, but they finish empty, cramping on the final climb and walking the last pitch. The training wasn't wrong. It just wasn't specific.
A gran fondo is 4-8 hours of varied intensity with climbs, descents, groups, and a fuelling problem that gets harder every hour. Preparing for it is not about racking up junk miles. It is about building aerobic capacity, raising sustained power, and rehearsing the specific demands of event day.
This is a 12-week plan. It assumes you are already riding 4-6 hours per week and can handle a 2-hour ride. If you cannot, extend the base phase by four weeks before starting.
What a gran fondo actually demands of you
A typical European gran fondo runs 100-180km with 1,500-3,500m of climbing. Ride time for a mid-pack amateur is 4-7 hours. The physiological demand is dominated by aerobic endurance, but it is punctuated by repeated 10-40 minute efforts at or near threshold on the climbs.
That combination is the key. A pure endurance ride at zone 2 is one problem. A 30-minute climb in hour five is another. The plan has to build both.
Fuelling is the second demand. A 5-hour ride at 200 watts burns roughly 3,500 calories. Even with 90g/hour of carbohydrate intake — the upper end of what a trained gut can absorb — you are running a 1,500-2,000 calorie deficit on the bike. Riders who have not trained their gut will start cramping and bonking around hour three. Our fuelling calculator gives you a per-hour target based on bodyweight and ride intensity.
The third demand is pacing discipline. A gran fondo is won or lost in the first 90 minutes. Riders who chase early groups, push too hard on the first climb, or sit at 90% of FTP in the peloton have nothing left when the decisive climbs come. Training for a fondo means training pacing as much as power.
Understand these three demands — aerobic capacity, fuelling, pacing — and the plan below makes sense as a response to each of them.
Phase 1: Aerobic base (weeks 1-4)
The first four weeks build the aerobic engine. Volume goes up, intensity stays controlled. The target is 80% of weekly time below 75% of FTP, with the remaining 20% as threshold or tempo work.
This is not junk-mile territory. Zone 2 riding has to be disciplined. If your long ride average heart rate is drifting above 75% of max, you are riding too hard and blunting the training effect. Prof. Stephen Seiler's work on polarised training, discussed at length on the Roadman Cycling Podcast, makes this point repeatedly: amateur riders spend too much time at moderate intensity and not enough time genuinely easy or genuinely hard.
Weekly structure for phase 1, assuming 10 hours available:
- Monday: rest or 30-minute spin
- Tuesday: 90 minutes with 3x10 minutes at tempo (85% FTP)
- Wednesday: 60-90 minutes zone 2
- Thursday: 75 minutes with 4x8 minutes at sweetspot (88-93% FTP)
- Friday: rest or 45 minutes zone 2
- Saturday: long ride, 3-4 hours zone 2
- Sunday: 90 minutes zone 2
Long ride progression across the four weeks: 3h, 3h30, 4h, 3h (recovery week). The recovery week is non-negotiable. Drop volume by 30-40% and keep one quality session to maintain fitness.
If you do not know your FTP, test it in week 1. A 20-minute all-out effort multiplied by 0.95 is a reasonable field estimate. Set your FTP zones from that number and use them to anchor every session that follows.
By the end of phase 1, a 4-hour ride should feel manageable, not crushing. If it does not, you need more base before moving on.
Phase 2: Sustained power (weeks 5-8)
Phase 2 shifts the focus. Aerobic volume stays high, but the quality sessions move from sweetspot to threshold and long tempo. The goal is raising the power you can hold for 20-60 minutes, because that is what climbs in a gran fondo demand.
Dan Lorang, who coached Jan Frodeno and Anne Haug and now heads performance at Red Bull-Bora-Hansgrohe, has been clear in multiple podcast conversations: long sustained efforts at threshold are the highest-return session for endurance athletes preparing for events over three hours. The adaptation is specific and it transfers.
Weekly structure for phase 2:
- Monday: rest or 30-minute spin
- Tuesday: 90 minutes with 2x20 minutes at threshold (95-100% FTP)
- Wednesday: 90 minutes zone 2
- Thursday: 2 hours with 3x15 minutes at upper tempo (88-92% FTP)
- Friday: rest or 45 minutes zone 2
- Saturday: long ride, 4-5 hours with 2x20 minutes at tempo mid-ride
- Sunday: 2 hours zone 2
Long ride progression: 4h, 4h30, 5h, 3h30 (recovery). Week 8 is the recovery week.
The Saturday long ride is now a specificity session. Inserting tempo blocks 2-3 hours in means practicing hard efforts on tired legs — exactly the demand of a climb in hour four of a fondo. Fuel these rides at 70-90g/hour of carbs to train the gut alongside the legs.
By the end of phase 2, your 2x20 minutes at threshold should feel repeatable. If it does not, retest FTP — it has likely risen 5-8% from phase 1. Adjust zones accordingly. Riders who hold onto stale FTP numbers undertrain in phase 3.
This is the phase where our cycling coaching clients see the biggest gains. The sessions are hard, the volume is high, and the margin for error on recovery is thin.
Phase 3: Event-specific sharpening (weeks 9-12)
The final four weeks are about specificity and taper. Volume drops modestly, intensity stays sharp, and sessions mirror the demands of event day.
Weeks 9 and 10 are the hardest weeks of the plan. Week 11 starts the taper. Week 12 is race week.
Week 9 structure:
- Tuesday: 90 minutes with 5x5 minutes at VO2 (110-115% FTP)
- Thursday: 2 hours with 2x30 minutes at threshold
- Saturday: 5-6 hour ride simulating event profile — sustained climbs if your event is mountainous, rolling tempo if it is not
- Sunday: 2 hours zone 2
Week 10 is similar but with a race-simulation long ride: 4-5 hours at event pace (65-75% FTP average) with 3-4 hard climbs ridden at 90-95% FTP. Fuel it at your target event rate. Wear your event kit. Use the bottles and gels you plan to race with. No new variables on race day.
Week 11 cuts volume by 25%. Keep one threshold session and one VO2 session, both short. The Saturday ride drops to 3 hours with two 15-minute tempo efforts.
Week 12 is taper proper. Monday and Tuesday easy. Wednesday 60 minutes with 3x3 minutes at VO2 to keep the system sharp. Thursday 45 minutes easy. Friday 30 minutes with 2-3 short openers. Saturday rest or 20-minute spin. Sunday: event day.
Taper reduces volume by 40-50% in the final week while preserving intensity. The research on taper is consistent across endurance sports: cutting volume without cutting intensity produces the largest performance gain. Riders who do nothing in the final week turn up flat. Riders who train through race week turn up tired.
If your event has a specific feature — a 40-minute climb, a technical descent, a crosswind section — ride it in phase 3 if you can. Specificity is worth more than generic fitness in the final four weeks.
Key weekly sessions
Five sessions carry the plan. Each one trains a specific adaptation, and each one scales across the three phases.
The sweetspot session. 3-5x8-15 minutes at 88-93% FTP with 3-5 minutes recovery. This is the highest-return session for building sustained aerobic power without the recovery cost of full threshold work. Use it in phase 1 and early phase 2.
The threshold session. 2-3x15-25 minutes at 95-100% FTP with 5-8 minutes recovery. This is the session that raises FTP itself. It is hard, it requires focus, and it benefits from a 10-minute warm-up and a protein-carb meal within an hour of finishing. Central to phase 2.
The VO2 session. 5-8x3-5 minutes at 110-120% FTP with equal recovery. This builds the top of your aerobic system and helps repeated short efforts on climbs. Introduced in phase 3.
The long ride. 3-6 hours at zone 2 with tempo or threshold blocks inserted in phases 2 and 3. This is the single most important session of the week. Skip a Tuesday interval if you have to. Do not skip the long ride.
The recovery ride. 30-60 minutes at genuine easy pace — under 65% of FTP, under 70% of max heart rate. If you are riding your recovery ride at tempo, it is not a recovery ride. It is a slow tempo ride, and it is stealing fitness from your next hard session.
Spacing matters. Two quality sessions should have 48 hours between them. The long ride follows two easy days. Riders who stack Tuesday, Wednesday, Thursday as hard days accumulate fatigue without training benefit.
Event-day pacing and fuelling
A gran fondo is a pacing exercise dressed up as a bike race. Riders who treat it as a race in the first hour pay for it in the fifth.
Target average power for event day sits at 65-75% of FTP. For a flat 100km, 75% is defensible. For a mountainous 160km, 65-70% leaves enough in reserve for the final climbs. Set a ceiling on the first climb of the day — never more than 90% of FTP regardless of who is ahead of you. The riders who attack the first climb are almost always the ones you pass on the last one.
Heart rate is a useful check alongside power. If heart rate is 10+ beats above where it should be for a given power output in the final third of the ride, you are cooked. Back off immediately. Eat and drink.
Fuelling targets: 70-90g of carbohydrate per hour, 500-750ml of fluid per hour depending on temperature, 400-800mg of sodium per hour. Start eating in the first 30 minutes, not when you feel hungry. Feeling hungry on the bike means you are already behind.
Tim Spector and other nutrition researchers have emphasised on the podcast that carbohydrate tolerance is trainable. Riders who practice 90g/hour in training handle it on event day. Riders who try it for the first time at kilometre 60 of their fondo find out about gut distress the hard way.
Pre-ride: a carbohydrate-focused meal 3 hours out, 60-80g carbs. A small top-up 30-60 minutes before the start. Caffeine 30 minutes before the start if you use it, 3mg per kg of bodyweight is a standard dose.
Pick your event, count back 12 weeks, and put the long rides in your calendar first. Everything else fits around those. If you want the sessions built around your exact power numbers, schedule, and event profile, that is what our cycling coaching does.
