In 1994, an Italian sports doctor named Michele Ferrari was trying to solve a problem. He wanted to compare climbing performances across different mountains — different gradients, different lengths, different altitudes. The trouble was obvious: a 40-minute climb up a 6 % gradient produces completely different speed and distance numbers from a 40-minute climb up a 10 % gradient, even if the rider's effort is identical.
Ferrari's solution was to strip the problem down to the one thing every climb shares: vertical gain. He called it Velocità Ascensionale Media — average ascent speed — and measured it in metres of elevation per hour. The formula removed road distance and gradient from the equation. It left a single number that could be compared across any mountain, any gradient, any length.
Three decades later, VAM remains the best single number for comparing climbing performances. It's built into Strava (they call it "VAM" under your ride stats on any climb segment), it sits in Garmin and Wahoo data fields, and it's the first thing physiologists look at when comparing ascents on different cols.
The formula
VAM is simple. Elevation gain in metres, divided by time in hours.
VAM = elevation gain (m) / time (hours)
Climb 800 metres of elevation in 45 minutes and your VAM is 1,067 m/hr. Climb 1,200 metres in 55 minutes and your VAM is 1,309 m/hr. The number tells you how fast you went up, regardless of road distance or how the gradient varied along the way.
To convert minutes into the decimal hours the formula requires: divide by 60. A 45-minute effort is 0.75 hours. A 38-minute effort is 0.633 hours. Or use the VAM Calculator and skip the maths.
One detail matters. VAM uses the time you spent climbing, not total time on the mountain. If you stop at a water fountain for three minutes or soft-pedal through a village, that time inflates the denominator and your VAM drops. For clean comparison, you want the moving time on the ascent, or the elapsed time from bottom to top without stops.
What VAM tells you (and what it doesn't)
VAM is excellent at one thing: comparing your climbing output across different mountains. If you climbed Alpe d'Huez at 1,050 m/hr in March and a completely different climb — say, the Stelvio — at 1,080 m/hr in June, you can reasonably conclude that your climbing fitness improved. That comparison would be much harder using speed or time alone, because the two climbs have different gradients, different lengths, and different conditions.
VAM is also useful for tracking fitness across the same climb over seasons. Your April attempt at a local 20-minute col produced 920 m/hr. July produced 1,010 m/hr. The fitness gain is visible in a single number.
What VAM doesn't tell you is equally important.
VAM can't compare riders on different gradients. A rider producing 4.0 W/kg will post a higher VAM on a 10 % ramp than on a 5 % slope. The physics of this are covered below, but the short version: steeper gradients mean more of your power fights gravity and less fights air resistance, so you convert more watts into vertical gain. A VAM of 1,100 m/hr on a 5 % climb represents substantially more power than 1,100 m/hr on a 10 % climb.
VAM doesn't account for altitude. Climbing at 2,500 metres reduces oxygen availability by roughly 25 %. A VAM of 1,000 m/hr at altitude represents a higher physiological cost than 1,000 m/hr at sea level.
VAM doesn't account for wind or temperature. A headwind on an exposed climb or a 38-degree July afternoon both reduce VAM without reflecting a fitness change.
VAM doesn't know about your bike. Total system weight — rider plus bike plus kit plus bottles — determines the power-to-weight ratio that drives the number. The rider who drops 2 kg of bike weight will see a VAM increase that isn't a fitness improvement.
These limitations don't make VAM useless. They make it a one-dimensional metric that works best when the conditions it ignores are held roughly constant. Same climb, same season, same equipment — VAM tracks fitness clearly.
The benchmarks
VAM varies enormously depending on the rider, the gradient, and the duration. These ranges are for sustained climbs of 20 minutes or more on gradients between 6 and 10 %, which is where the number is most meaningful.
Recreational cyclists (first couple of years riding, limited structured training): 400–700 m/hr. This is the range for the rider who can get up a mountain but isn't racing the clock. On a typical Alpine col, this means 90+ minutes for 1,000 metres of gain.
Club cyclists (regular group rides, some structured training): 700–1,000 m/hr. The rider who trains consistently and rides with faster groups. The upper end of this range — 950-1,000 m/hr — is a solid amateur performance on most cols.
Trained amateurs (structured training, racing or sportive-focused): 1,000–1,300 m/hr. The Cat 3-4 racer or the serious sportive rider who tackles Marmotte or Etape. A VAM above 1,200 m/hr on a sustained climb represents a strong power-to-weight ratio, typically 4.0+ W/kg.
Elite amateurs and domestic professionals: 1,300–1,500 m/hr. Cat 1-2 racers, national-level competitors. Sustained W/kg of 4.5–5.5 on long climbs.
WorldTour professionals (Grand Tour climbers): 1,500–1,800 m/hr. The numbers that appear on summit finishes at the Tour de France and Giro d'Italia. At the upper end — above 1,700 m/hr sustained for 30+ minutes — the figures have historically been associated with performances that prompted scrutiny. Ferrari's original work was partly motivated by identifying outlier performances using VAM as a screening tool.
For reference, Tadej Pogacar's ascent of Plateau de Beille in the 2024 Tour de France was recorded at approximately 1,780 m/hr for 40 minutes. Marco Pantani's era-defining climbs in the late 1990s produced similar numbers on different mountains. The consistency of those upper-boundary figures across eras says something about the physiological ceiling of human climbing performance — or about the pharmacological support behind it, depending on your reading of cycling history.
VAM and W/kg: the physics
On steep climbs, VAM and watts-per-kilogram are tightly related. The simplified physics produces a rough conversion:
W/kg (total system) ≈ VAM / 367
This approximation works on gradients above about 5 %, where gravity dominates the resistance equation. On a steep mountain pass, a rider with a VAM of 1,100 m/hr is producing approximately 3.0 W/kg of total system weight (rider + bike + gear). A rider at 1,470 m/hr is producing approximately 4.0 W/kg.
The number 367 comes from a simplified version of the climbing power equation. When gradient is steep enough that aerodynamic drag becomes a small fraction of total resistance, the relationship between climbing speed and power-to-weight approaches a linear constant. That constant — close to 367 for typical cycling conditions — gives a fast mental conversion.
Where the approximation breaks down:
Shallow gradients. On a 3 % climb, aerodynamic drag is a large fraction of total resistance. The same 4.0 W/kg rider goes faster on the road (because the gradient is gentle) but posts a lower VAM (because less of the speed is directed upward). The relationship between W/kg and VAM loosens, and the / 367 conversion overestimates the rider's actual power-to-weight.
Very steep gradients. On a 12 % ramp, rolling resistance and mechanical losses become relatively more important. The approximation still works reasonably well, but the constant shifts slightly.
High speeds. If you're climbing fast enough for aerodynamic drag to matter — typically above 25 km/h, which happens on shallower gradients — the approximation drifts. The Power-Speed Calculator handles the full physics.
For practical purposes: on a 7-10 % climb lasting 20 minutes or more, VAM / 367 gives you a credible estimate of your total system W/kg. To get your body W/kg, subtract bike weight from total system weight and recalculate. Most riders carrying an 8 kg bike will find their body W/kg is about 0.2-0.3 higher than the total system figure.
Use the W/kg Calculator to check your ratio from a power test, then compare against the VAM / 367 figure from a real climb. If the two numbers broadly agree, your climbing is efficient. If your lab W/kg is significantly higher than what your VAM implies, something is costing you watts on the road — pacing, wind, altitude, or excess equipment weight.
Why gradient changes everything
This is the piece that confuses people when they compare VAM across different climbs. The same rider, producing the same power, will post a higher VAM on a steep climb than on a shallow one.
Consider a rider producing exactly 300 watts at a total system weight of 80 kg (3.75 W/kg). On a 5 % gradient, they might be travelling at 18 km/h. On a 10 % gradient, the same power produces perhaps 10 km/h. The speeds are very different, but the vertical gain per hour reverses the ranking:
- At 18 km/h on a 5 % grade: vertical speed is 18,000 m/hr x 0.05 = 900 m/hr
- At 10 km/h on a 10 % grade: vertical speed is 10,000 m/hr x 0.10 = 1,000 m/hr
The rider is slower on the steep climb but climbing faster vertically. The reason is aerodynamic drag. On the 5 % climb, a meaningful chunk of the 300 watts is fighting air resistance at 18 km/h. On the 10 % climb, very little of the 300 watts fights air at 10 km/h — almost everything goes into fighting gravity.
This is why Ferrari and subsequent analysts focused on gradients above 5-7 % when using VAM as a performance metric. Below that threshold, aerodynamic differences between riders — body size, position, equipment — contaminate the comparison. Above it, the metric isolates climbing ability cleanly.
The practical takeaway: don't compare your VAM on a 4 % drag up a valley road with your VAM on a 9 % mountain pass. They measure different things.
Famous climbs and reference VAMs
Part of what makes VAM useful is the database of reference values that three decades of power data have built up. Here are some of the most-ridden climbs in cycling and the VAMs you can expect at various levels.
Alpe d'Huez (1,071 m elevation gain, average 8.1 %, 13.8 km)
The benchmark climb. Twenty-one numbered hairpins from Bourg d'Oisans to the ski station. The gradient is consistent enough that VAM comparisons are reliable.
- Recreational cyclist: 600–800 m/hr (80–105 minutes)
- Trained amateur: 900–1,100 m/hr (58–71 minutes)
- Strong amateur racer: 1,100–1,300 m/hr (49–58 minutes)
- Pro Tour: 1,500–1,750 m/hr (37–43 minutes)
Marco Pantani's 1997 record ascent took 36 minutes 50 seconds — a VAM of approximately 1,744 m/hr. That time has stood for nearly 30 years, which tells you something about the era it came from.
Mont Ventoux — Bedoin side (1,617 m elevation gain, average 7.6 %, 21.4 km)
Longer and more variable than Alpe d'Huez. The first six kilometres through the forest are shallow (4-5 %), then the road opens out above the treeline and the gradient stiffens to 9-10 % for the final push to the summit. VAM comparisons work best for the upper section above Chalet Reynard, where the gradient is more consistent.
- Recreational cyclist: 500–700 m/hr (2.5–3.5 hours for the full climb)
- Trained amateur: 800–1,000 m/hr (1.5–2 hours)
- Strong amateur racer: 1,000–1,200 m/hr (80–95 minutes)
- Pro Tour: 1,400–1,700 m/hr (57–70 minutes)
The Ventoux is deceptive because the shallow opening kilometres produce low VAM that drags down the overall figure. Measuring VAM from Chalet Reynard to the summit (6 km, ~500 m gain, average 8.5 %) gives a cleaner climbing metric.
Passo dello Stelvio — Bormio side (1,533 m elevation gain, average 7.1 %, 21.5 km)
The highest paved pass in the Eastern Alps. Altitude matters here — the summit sits at 2,758 metres, where oxygen availability drops noticeably. Your VAM on the Stelvio will be lower than on an equivalent sea-level climb, and the difference widens the higher you go.
- Recreational cyclist: 450–650 m/hr (2.5–3.5 hours)
- Trained amateur: 750–950 m/hr (1.5–2 hours)
- Strong amateur racer: 950–1,150 m/hr (80–95 minutes)
- Pro Tour: 1,350–1,600 m/hr (57–68 minutes)
Notice the numbers are lower across the board. The altitude effect is real — roughly 5-8 % reduction in sustainable power for every 1,000 metres above sea level for unacclimatised riders.
Four things that move the number
If your VAM isn't where you want it, four factors control the output. Fix them in order of impact.
1. Threshold power
VAM on sustained climbs correlates most tightly with your functional threshold — the power you can hold for 40-60 minutes. Building FTP through structured training is the single most reliable way to increase VAM. Sweet spot work (88-93 % of FTP, sustained for 10-20 minute blocks), threshold intervals, and over-under sessions all target the physiological systems that drive sustained climbing power.
The progression rate matters for expectations. A first-year cyclist with structured training might gain 30-50 watts of FTP in a year. A fifth-year cyclist might gain 5-15. The room for improvement narrows as training age increases, but it rarely closes completely. Prof. Stephen Seiler's body of work on training intensity distribution — the 80/20 polarised model — provides the framework for building that threshold without burning out. Most amateurs who plateau on VAM are either training too hard too often (accumulating fatigue without adaptation) or not training hard enough when they do go hard (spending too much time in the middle zone).
2. Body composition
W/kg has two sides. Power is the ceiling; weight is the floor. For most amateur cyclists, there's more to gain from careful body composition work than from another 10 watts of FTP.
The maths illustrates why. A 78 kg rider producing 280 watts has 3.59 W/kg. Losing 3 kg of body fat (without losing power) takes that to 3.73 W/kg — a 4 % improvement. Gaining 10 watts on 78 kg takes W/kg from 3.59 to 3.72. The body composition route is often faster and more accessible than the power route, particularly for riders who carry more body fat than their performance goals require.
The caveat is critical: losing weight at the expense of power is counterproductive. A 2 kg weight loss that comes with a 15-watt power drop leaves you slower, not faster. Periodised body composition work — fuelling training days fully, running modest deficits on rest days, protecting muscle through adequate protein — is the approach that preserves both sides of the ratio. The body composition for cyclists guide covers the protocol.
3. Pacing discipline
The same rider with identical fitness can produce meaningfully different VAMs on the same climb depending on pacing. Going too hard in the first quarter of a climb accumulates an oxygen debt that drops power in the second half. The net effect is a lower average power and a lower VAM than the same rider holding a steady, slightly conservative effort from bottom to top.
The evidence from studies on pacing in cycling time trials — and from the practical experience of coaches like Tim Kerrison, who built Team Sky's climbing protocols — is consistent. Slightly negative splits (starting conservative, finishing slightly harder) or even pacing produce the best sustained power on climbs lasting 15 minutes or more. Positive splits (starting hard, fading) almost always produce a lower average.
On a practical level, this means starting the first five minutes of a 30-minute climb at 5-10 watts below your target average. It will feel too easy. That's the signal that you're doing it right. The riders who drop you in the first three minutes and then come back to you at minute twenty were always available to catch — you just needed the discipline to let them go early.
The pacing strategy guide for long climbs covers this in detail, including the data behind why steady-state efforts outperform surge-and-recover patterns on climbs.
4. Familiarity with the climb
This factor is underrated. Knowing a climb — where the gradient eases, where it kicks up, where to shift gears, where to drink, where the wind typically hits — produces a measurably better performance than riding the same climb cold. Part of this is pacing (you can plan your effort around the known profile). Part of it is psychological (nothing surprises you, so you don't waste mental energy on uncertainty). Part of it is tactical (you know where to sit on the saddle, when to stand, when the final ramp starts).
If you're targeting a specific climb for a sportive or event, ride it in training. Twice is better than once. Three times is better than twice. Study the profile beforehand so you know what's coming. The first time up any mountain is always the slowest, and the gap between first and third attempts on the same climb can be 5-10 % in VAM — without any fitness change.
Tracking VAM over time
VAM becomes most useful when you build a personal reference library. Pick two or three local climbs that you ride regularly — ideally above 5 % average gradient and lasting at least 15 minutes. Ride them at full effort every 4-6 weeks through the season and record the VAM.
The trendline across a season tells you more than any single number. A VAM that rises steadily from March through June suggests your training is working. A VAM that flattens or drops suggests fatigue accumulation, overtraining, or a training programme that has stopped producing adaptation.
Comparing across years is equally useful. If your best June VAM this year is 50 m/hr higher than your best June VAM last year, you've made a meaningful gain. That single comparison tells you more about your climbing fitness trajectory than weeks of lab testing.
For precise tracking, the VAM Calculator takes elevation gain and time and returns your VAM instantly. Log the results alongside the climb, conditions, and how you felt. Three data points on the same climb across a season give you a legitimate fitness trajectory.
Where to start
If you're new to thinking about VAM, the first step is to calculate it for your recent climbing efforts. Pull up a Strava segment or a Garmin activity from a climb you know well, note the elevation gain and time, and run the numbers. Then find the same climb from three or six months ago and compare.
The number you see is where you are. The benchmarks above tell you where that sits relative to other riders. The four factors — threshold power, body composition, pacing, familiarity — tell you what to work on.
Use the VAM Calculator for quick calculations, the W/kg Calculator to check your power-to-weight, and the Power-Speed Calculator to model the full physics of climbing at different gradients and weights. If you want to go one step further and estimate your total ascent time on a specific col before you ride it, the Climbing Time Estimator runs the full physics model with presets for Alpe d'Huez, Ventoux, Galibier, and more. Between those tools and a few months of structured work, the number moves.