October 17, 2026 · 13 min read

What kind of rider am I? Power curve, critical power and rider profile

The Performance tab on the Progress page answers the question everyone asks once they start riding with a power meter: what kind of rider am I? A sprinter who gets dropped on the climb, or a diesel who will never win a sprint? I checked it on my own 2026 season, and the answer surprised me twice. This is the second article in the series about the Progress page — after the Form tab.

What is on the Performance tab

The Performance tab has ten cards. Four of them answer the question in the title, and they are the subject of this article:

The remaining cards — zones, energy systems, intensity distribution, efficiency and power by grade — are covered in the next articles in the series.

The power curve: your best power for every duration

The power curve shows the best average power you held for 30 seconds, one minute, 3, 5, 8, 10, 20, 30, 60 and 90 minutes in the selected period. Each point is a different effort, often from a different ride. The time axis is logarithmic, because the difference between 30 seconds and a minute matters as much as the difference between an hour and an hour and a half. I write more about the curve itself in the article on the power curve. This is my season:

The most important thing to know about this curve: it shows what you rode, not what you can do. All my records from 3 to 10 minutes come from a single ride — the ramp test on 16 September, whose last minutes are ridden to failure. The 20, 30 and 60-minute records come from one June ride from Strava. My best 20 minutes is 165 W, only 90% of FTP — not because I can't go harder, but because this season I never rode 20 minutes flat out.

So a dip in the curve is usually a missing attempt, not a weakness. If you want the curve to tell the truth about a duration, you have to ride that duration hard at least once.

Comparing with the previous period

Above the chart there is a “Compare with previous period” checkbox. It adds the curve from a period of the same length that ends the day before the selected one — for “90 days” that is the previous 90 days. For me it compares autumn with spring:

In autumn I was stronger over one minute (+25 W) and over 3–10 minute efforts (+5 W), and weaker over 20 minutes and an hour (−7 to −11 W). That is exactly the picture of my training: in autumn I did ERG intervals and one ramp test, and no long, hard ride. The curve is not saying I lost endurance — it is saying I didn't test it. The exception is 90 minutes (+6 W): one long sweet spot session in ERG mode on 6 October.

Critical power and the W′ reserve

Above the curve the app shows four numbers: critical power (CP), the W′ reserve, the fit quality and how many efforts they were computed from. CP is the power you can theoretically hold for a very long time; W′ is the store of work you can spend above it before you have to slow down [1, 2]. The model is simple:

P(t) = CP + W′ / t

The app fits it to your best efforts between 2 and 12 minutes — in my case the 3, 5, 8 and 10-minute records — and needs at least three such points. My results:

W′ is easiest to understand with an example. 8.3 kJ is 8300 J. If I ride at 250 W, which is 66 W above CP, I spend 66 J per second and the reserve runs out after about 126 seconds. At 200 W, only 16 W above CP, it would last almost 9 minutes. That is why a short, sharp attack costs as much as a long, moderate surge. I write more about work above threshold in the article on FRC.

The fit quality is shown on purpose. An R² of 0.90 is lower than I would like, and all four points come from one ramp test, in which consecutive minutes are not separate all-out efforts. So my critical power describes the end of a ramp rather than what I would ride in a race. Compared with spring (179 W) it rose by 6 W — and here too it's worth remembering that both numbers come from ramp tests. How to read a ramp test result itself, I describe in the article on interpreting a ramp test.

Rider profile: the shape, not the number

The rider profile takes five best efforts — 30 seconds, one minute, 5, 20 and 60 minutes — and divides each by your FTP. That way it needs neither your weight nor tables of other riders' results: it compares you with yourself. The result is a pentagon, which the app sets against the reference shape of a typical all-rounder:

The rule is simple. Each axis is divided by the reference. Then the app compares the short end (the average of 30 seconds and one minute) with the long end (the average of 20 and 60 minutes), and the 5 minutes with both. If one side beats the other by at least 0.08, you get a name: Sprinter, Diesel or Puncheur. If nothing stands out — All-rounder.

For the whole season my short end beats the long one by 0.055 — not enough to name a type. For the last 90 days it is 0.086, because the June one-hour ride dropped out of the period and the 20 and 60 minutes fell. I did not become a sprinter between June and October. I simply stopped riding long, hard stretches, and the profile noticed. That is why the card says it plainly: read the shape, not a single number.

One note about the axes. They are all multiples of today's FTP, so when FTP rises, the whole pentagon shrinks even though the watts stay the same. My FTP rose this season from 114 W in April to 184 W in September — April's profile on today's FTP would look like the profile of a much weaker rider. If you want to compare yourself with other riders' tables, other tools are made for that — I write separately about the power profile in the 4DP test and about W/kg tables.

Records

The Records card shows the best power for every duration — from 30 seconds to 90 minutes — and your recent attempts below it. Gold dots are personal records; clicking a point opens the ride it came from. You can add your own segments from 30 seconds to 2 hours, for example an “8-minute climb” if you often ride the same stretch.

It is the only card on the Progress page that does not depend on the selected period — a record is a record for good. That is why it's worth reading it together with the power curve: the curve tells you what you can do now, the records what you could ever do. My 20–60 minutes from June are records today that the curve for the last 90 days no longer contains.

Weight and W/kg

The last card shows your body weight from weigh-ins and W/kg, which is FTP divided by weight. More interesting than the number itself is that the app splits every W/kg change into two parts: how much came from the change in FTP, and how much from the change in weight.

In three weeks W/kg rose from 1.85 to 1.98. Almost half came from FTP, the other half from 3 kilograms less. That is an important distinction: W/kg improved by weight only helps uphill, while W/kg improved by watts helps everywhere. I write about when W/kg matters and when it doesn't in the article is W/kg the only metric that matters.

What I take away from this

Next in this series: zones, energy systems and intensity distribution — in other words, whether I train in the right proportions.

Sources

1. Monod H, Scherrer J. The work capacity of a synergic muscular group. Ergonomics. 1965;8(3):329–338. doi:10.1080/00140136508930810
2. Jones AM, Vanhatalo A, Burnley M, Morton RH, Poole DC. Critical power: implications for determination of VO2max and exercise tolerance. Med Sci Sports Exerc. 2010;42(10):1876–1890. doi:10.1249/MSS.0b013e3181d9cf7f
3. Pinot J, Grappe F. The record power profile to assess performance in elite cyclists. Int J Sports Med. 2011;32(11):839–844. doi:10.1055/s-0031-1279773
4. Allen H, Coggan AR, McGregor S. Training and Racing with a Power Meter. 3rd ed. Boulder, CO: VeloPress; 2019.

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