Training for High-Mountain Cycling: What a Dolomites Granfondo Actually Demands

A Dolomites-style granfondo is not primarily a fitness test. It is a pacing and nutrition management problem set against the backdrop of several thousand metres of vertical climbing. The field includes riders of widely varying ability; the difference between a good day and a suffering one usually comes down to whether the first hour up Passo Gardena or Passo Giau was ridden five watts over threshold rather than at it.

The Maratona dles Dolomites, held each July in South Tyrol, offers three distances: the Sportiva (55 km, 1,780m elevation), the Sellaronda (106 km, 3,273m), and the Maratona (138 km, approximately 3,986m). All start in Corvara and cross a sequence of Dolomites passes that includes Passo Campolongo, Passo Giau, and Passo Falzarego, depending on the selected distance. The Maratona course uses seven major passes; Passo Giau — 9.9 km at 9.3% average gradient, summit at 2,233m — is typically the hardest single sustained effort of the day.

Preparation for this format differs from training for a flat century or a criterium. The body's ability to sustain power at 5–8% gradient for 30–50 continuous minutes, repeatedly over a six-to-eight-hour day, is specific and trainable.

What You're Actually Training For

The physiological demands of extended climbing differ from flat-road riding in two important ways. Cadence is typically lower — 60–75 rpm rather than 85–95 rpm — and muscular fatigue accumulates faster because the loading is more constant. There is no freewheeling or downhill recovery during the climb itself.

This means specific work matters more than just accumulating kilometres. Riders preparing for a high-mountain event should spend structured time at lower cadences: long steady-state efforts of 20–40 minutes at 65–70 rpm train the muscular endurance specific to climbing. This is uncomfortable at first for riders accustomed to spinning, but the adaptation develops within four to six weeks of consistent exposure.

Training on actual climbs, rather than rollers or flat roads, is also more valuable than it might sound. The gradient-specific neuromuscular pattern of sustained climbing is not easily replicated on flat terrain even with good power management. If you live in flat country, two or three targeted training camps in the 12 weeks before the event — or an indoor trainer with meaningful gradient simulation — fill that gap. The Alps, the Pyrenees, and the Dolomites themselves are the obvious camp destinations.

Back-to-back long days are the third structural element most flat-terrain riders miss. A single long weekend ride does not prepare the body for cumulative fatigue the way a Saturday five-hour ride followed by a Sunday three-to-four-hour ride does. Four to six back-to-back pairs in the final ten weeks of preparation is standard for riders targeting a strong Maratona finish.

Pacing the Race

Most amateur riders approach a granfondo with a power meter or heart rate monitor but no clear pacing strategy. The result is overcooking the first major climb, suffering a progressive power decline from kilometre 60 onward, and arriving at the final pass working well below potential.

A working framework for a 4,000m granfondo:

First major climb: ride 5–10% below your sustainable 60-minute power. It feels conservative — it is. The Dolomites do not reward bravado in the first hour.

Middle section: settle into 80–90% of threshold for sustained climbs. Downhill and flatter sections are recovery, not opportunities to compensate for the uphills.

Final 40 km: if pacing has been honest to this point, you should be able to hold close to the power you maintained on the first climb. If you cannot, the first hour was too hard.

Heart rate lags effort on sustained climbs. At altitude — the Dolomites passes sit between 1,800–2,300m — cardiac drift occurs even at steady watts, and perceived exertion at elevation runs higher than at sea level. Power is the more reliable guide; if you are working without a power meter, deliberate conservatism in the first 90 minutes is the appropriate substitute.

Most Dolomites granfondos start at 1,200–1,400m above sea level and reach passes above 2,000m. For riders based at sea level, the altitude effect is modest but real. Aerobic capacity decreases roughly 3% per 300 metres of altitude gain above 1,500m (the precise figure varies between individuals). At 2,200m, a rider accustomed to sea level is working against meaningfully reduced oxygen availability.

Arriving 48–72 hours before the event allows enough time to begin adjusting without the deep fatigue of full altitude acclimatisation. Arriving the same day or day before removes the early adaptation window. Riders with two or more weeks available can pursue a proper altitude camp at 2,000–2,500m — the training effect from red blood cell production begins to consolidate after approximately 10 days at altitude; below that, managing acute symptoms is the priority.

Nutrition for a Full-Day Effort

The energy cost of a 4,000m granfondo runs 3,000–5,000 kcal for most riders. Feed stations on the Maratona dles Dolomites are well-stocked, but practising race-day nutrition in training removes the guesswork.

The practical standard: 60–80 grams of carbohydrate per hour for the climbing portions. This is more than most riders take on a training ride and requires gut training. Four to six weeks of practising high carbohydrate intake on long rides reduces the GI distress many athletes experience when they attempt race-level volumes for the first time on race day.

Salt supplementation matters more than many riders appreciate on warm July days in the mountains. Sweating at altitude and in mountain sun depletes electrolytes at a rate similar to sea-level racing; the dry mountain air increases insensible water loss beyond what thirst reliably signals.

The Week Before

Taper conservatively. Riders who train heavily in the final week before a multi-day high-altitude event arrive tired. A structured taper — reducing volume by 30–40% while maintaining some intensity through short, sharp efforts — is the standard approach for events of this length. The legs feel best on days three to five of a taper; most Dolomites riders travel to the start region during this window to adapt to the altitude before taper fatigue sets in.

Passo Giau climbs at around 9.3% for nearly 10 km. That gradient, sustained for 40–50 minutes at altitude, separates riders who trained for it from those who hoped fitness alone would be enough. There is no shortcut — but there is a very clear path.