Training Calculator

Calculate training zones, find interval targets, and understand the relationship between intensity, lactate, and duration.

Your values

Highest power you can sustain for ~1 hour. Test: 4×12 min average × 0.95.

Showing example values (FTP 250 W, 75 kg, max HR 185). Enter your own values above.

Power Zones

Zone 1 — Recovery
< 138
Zone 2 — Endurance
Zone 3 — Hard aerobic
Zone 4 — Threshold
Zone 5 — VO2max
138200 W
200238 W
238263 W
263300 W
NM
300+
ZonePower% FTP
Zone 1 — Recovery< 138 W< 55%
Zone 2 — Endurance138–200 W55–80%
Zone 3 — Hard aerobic200–238 W80–95%
Zone 4 — Threshold238–263 W95–105%
Zone 5 — VO2max263–300 W105–120%
Zone 6 — Anaerobic300–375 W120–150%

Power-Duration Model

What can you hold, and for how long? Typical values relative to FTP.

50%75%100%125%150%FTPCP1 min2 min5 min10 min20 min60 min3 t5 t1 min2 min5 min10 min20 min60 min3 t5 t
Duration% FTPPower
1 min150%375 W
2 min132%330 W
5 min117%293 W
10 min107%268 W
20 min105%263 W
60 min100%250 W
3 t77%193 W
5 t68%170 W

Above threshold, it's a countdown — the higher the power, the shorter the duration. Below threshold, you can sustain for hours. The curve follows the critical power model: P(t) = CP + W'/t, where CP is the highest power you can sustain over a long duration.

Critical power model: Morton (2006), Eur J Appl Physiol 96(4):339–354. Power profile values: Pinot & Grappe (2011), Int J Sports Med 32(11):839–844. CP ≈ 96% of FTP: Borszcz et al. (2019), Int J Sports Med 40(11):737–742.

FTP Estimation from Interval Session

Enter your intervals — duration, power, and rest for each effort. Choose a standard format or enter custom values. The calculator estimates FTP and training zones.

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Heart Rate Zones — Olympiatoppen Intensity Scale

The official Norwegian zone model (version 2, 2024). Based on data from 160 elite endurance athletes.

I-1 Very light
I-2 Fairly light
I-3 Somewhat hard
I-4 Hard
I-5 Very hard
102133 bpm
133152 bpm
152161 bpm
161170 bpm
170185 bpm
ZoneHeart rate% max HR
I-1 Very light102133 bpm5572%
I-2 Fairly light133152 bpm7282%
I-3 Somewhat hard152161 bpm8287%
I-4 Hard161170 bpm8792%
I-5 Very hard170185 bpm92100%

Anaerobic zones (heart rate is not a reliable guide)

I-6 Very very hard

RPE 19–20 · 1–3 min

A few short words while gasping. 1–3 minutes.

I-7 Sprint

RPE 20 · 15–60 s

15–60 second efforts. Peak lactate post-effort.

I-8 Explosive

RPE max · 3–15 s

3–15 seconds maximal mobilization.

Source: Olympiatoppen Intensity Scale v2 (2024), olt-skala.nif.no

Lactate Model

How blood lactate responds to intensity and duration — and why 'lactate zones' above threshold don't make sense.

Lactate vs. intensity

Zone 2Sweet SpotFTP24681012LT1 (~2.0)LT2 (~4.0)40%50%60%70%80%90%100%110%120%% FTPLaktat (mmol/L)

Lactate vs. time above threshold

At threshold (100% FTP), lactate stabilizes. Above threshold, it rises continuously — the higher the intensity, the faster.

24681012100 % FTP105 % FTP110 % FTP120 % FTP0102030405060Time (minutes)Laktat (mmol/L)

Above threshold, lactate rises continuously over time. A reading of 6 mmol/L could mean minute 15 at 105% FTP or minute 2 at 120% FTP — the same number, completely different physiological states. That's why it's more precise to talk about duration and power than lactate zones above threshold.

Training conceptLactate% FTPPower
Zone 2 — Endurance1.0–2.0 mmol/L5580%138200 W
Zone 3 — Hard aerobic2.0–4.0 mmol/L8095%200238 W
Zone 4 — Threshold (MLSS)3.5–5.5 mmol/L95110%238275 W
Zone 5 — VO2max (rising)> 5 ↑ mmol/L110120%275300 W

Lactate curve: exponential model based on Faude et al. (2009), Sports Medicine 39(6):469–490. Lactate accumulation above threshold: Jones et al. (2008), Am J Physiol 294(2):R585–R593. MLSS definition: Heck et al. (1985), Int J Sports Med 6(3):117–130. Optimal zone 2 (1.5–1.8 mmol/L): San Millán & Brooks (2018), Sports Medicine 48(2):467–479.

How Do You Compare?

Compare your FTP/kg with Coggan's power profile table.

Your FTP: 250 W / 75 kg = 3.33 W/kg

Male (W/kg)

Level5 s1 min5 minFTP
World Class23.310.86.935.82
Exceptional21.510.16.315.29
Excellent (Cat I)19.79.45.694.76
Very Good (Cat II)17.98.75.074.22
Good (Cat III)16.28.04.453.69
Moderate (Cat IV)you14.47.33.833.16
Fair (Cat V)12.66.63.212.62
Untrained10.85.92.592.09

Female (W/kg)

Level5 s1 min5 minFTP
World Class18.28.85.694.76
Exceptional16.78.25.184.33
Excellent (Cat I)15.37.64.673.90
Very Good (Cat II)13.97.04.163.46
Good (Cat III)12.56.43.653.02
Moderate (Cat IV)11.15.93.142.59
Fair (Cat V)9.75.32.632.15
Untrained8.34.82.121.71

Modern context: Coggan's table vs. today's elite

Coggan's table was published around 2010 and has not been updated. Current Grand Tour riders exceed its top values. Pogačar and Vingegaard produce 6.8–7.0 W/kg over 30–40 minutes after hours of racing — their rested FTP is likely well above the table's 'World Class' ceiling of 6.04 W/kg.

RiderDurationW/kgEvent
Pogačar40 min~7.0Plateau de Beille, TdF 2024
Vingegaard13.5 min~7.5Stage 16 TT, TdF 2023
Van der Poel3.3 min6.85Koppenberg, Ronde 2022
Evenepoel~30 min~6.7Key climbs, TdF 2024

Table: Coggan & Allen (2010), 'Training and Racing with a Power Meter'. Modern data: Portoleau / chronoswatts.com (TdF 2024 analyses), welovecycling.com, Cyclingnews.

VO2max Estimator

Estimate your maximal oxygen uptake from various test methods. Field estimates have ±5–10% error margin compared to lab testing.

Highest average power you can hold for exactly 5 minutes.