CyclingVO2maxIntermediate 49 min

30/30 intervals on the bike (2 × 10)

30/30 intervals for cycling: two sets of 10 × 30 seconds at 120–130% of FTP, your estimated maximal aerobic power, with 30 seconds easy between. 10 minutes at that power in a 49-minute session. The simplest way into VO₂max work without going deep into the red.

Written by Pierre Halloo · Updated 25 October 2026

Session profile43 blocks

At a glance

Duration: 49 min
Main target: 120–130%FTP6 Z6 · Anaerobic
Time at target: 10 min
Estimated load: 47
Structure: 2 × (10 × 30″ at 120–130% FTP, 30″ recovery), 5′ between sets
Level: Intermediate
Equipment: Power meter · Smart trainer

The session in detail

FTP

Time in zone

Z120 min
Z219 min
Z610 min

What the targets mean

The session's targets, in watts for three reference FTPs
Target	Zone	Time	FTP 200 W	FTP 250 W	FTP 300 W
120–130%	6Anaerobic	10 min	240–260 W	300–325 W	360–390 W
55–65%	2Endurance	9 min	110–130 W	138–163 W	165–195 W
45–55%	1Recovery	10 min	90–110 W	113–138 W	135–165 W

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What this session is for

30/30s build your VO₂max and your maximal aerobic power (MAP). You can only hold MAP in one go for a few minutes. Chop it into 30-second pieces with 30 seconds of active recovery and you can rack up 10 minutes without blowing, while your oxygen uptake stays high from one rep to the next, because 30 seconds isn't long enough for it to fall back.

The format comes from running: Billat's 2000 study measured that time spent near VO₂max. On the bike it's widely used, especially in French coaching, which works in % of MAP, but no dedicated cycling study has been found.

Who it's for

Intermediate riders trying VO₂max work for the first time: the efforts are short, there's one target, and you can cut a set short without wrecking the session. You need a recently measured FTP. If you run as well, 30/30 running intervals are the original version.

When to do it

One or two VO₂max sessions a week is a common guideline, with at least one easy day between hard sessions. Avoid the day before a long ride or a race. To progress, first go to 3 × 10, then to formats with shorter recoveries: 40/20s, then Rønnestad's 30/15s.

How to do it

Warm-up
15 min
5′ at 45–55% FTP + 5′ at 56–65% FTP + 5′ at 66–75% FTP
15 minutes building from 45 to 75% of FTP, in 5-minute steps. On a smart trainer, switch to resistance or slope mode now: you'll need it for the main set.
Main set
24 min
2 × (10 × 30″ at 120–130% FTP, 30″ recovery), 5′ between sets
Two sets of 10 × 30 seconds at 120–130% of FTP, or 300 to 325 W for an FTP of 250 W, each followed by 30 seconds at 55–65%, or 138 to 163 W, with 5 easy minutes between sets. It isn't a sprint: aim for the same power from the first rep to the last. In ERG mode the trainer takes several seconds to follow each change, and 30 seconds goes quickly: in resistance or slope mode, you set the power yourself, to the watt. Keep pedalling through the easy 30 seconds.
Cool-down
10 min
10′ at 40–55% FTP
10 very easy minutes at 40–55% of FTP. If the last reps of the second set dropped below 120%, keep the same target next time before thinking about a third set.

How it should feel

The first reps feel easy, almost too easy. Around the seventh, your heart rate stays high even through the easy 30 seconds, and the last few of each set are very demanding. The turbo in ERG mode, meanwhile, takes ten seconds to notice the block has changed. Guide: 8 to 9 out of 10.

Common mistakes

Sprinting the 30 seconds

With a 300 W target, it's easy to go off at 450 W. The set then collapses by the fifth rep. 30/30s are ridden at your MAP, a power you should be able to repeat ten times in a row, not flat out.

Letting ERG mode drive

ERG mode smooths out power changes: over 30 seconds, it spends a good chunk of the effort ramping up or down. Resistance or slope mode gives you the right power straight away, as long as you pace it yourself.

Freewheeling the recoveries

The easy 30 seconds are an active recovery, at 55–65% of FTP. Coast and your legs cool off and your heart rate drops too far: each rep starts from further back, and the format loses its point.

Treating MAP as a fixed ratio

120–130% of FTP is an estimate of your MAP, which varies between riders. If you know your measured MAP, aim for 100–110% of it, as French coaching prescribes.

When to skip it

Before you start

A recently measured FTP.
A few weeks of regular endurance riding behind you.

Skip it if

You're very tired, or a long ride or race is planned for the next day.
You have doubts about your health: get medical advice before near-maximal efforts.

Origin and evidence

Level of evidence

Moderate evidenceLevel 3 of 5

30/30s come from running. Billat and colleagues (Eur J Appl Physiol 2000), in 8 distance runners: taken to exhaustion, 19 reps on average, 30/30 at 100% and 50% of the speed at VO₂max kept them at VO₂max for 7 min 51 s, against 2 min 42 s for a hard continuous run. The cycling version is widely used, but no dedicated cycling study has been found. French coaching prescribes 30 seconds at 100–110% of MAP and 30 seconds between zones I2 and I3. Some practitioners find 30/30s less effective than 30/15s for reaching VO₂max, with no direct comparison on the bike. The MAP estimate of 120–130% of FTP, the 55–65% recovery, the 2 × 10 split, the warm-up and the cool-down are Wattson choices. Bottom line: good evidence for the running protocol, moderate for its transfer to cycling.

Sources

Billat V. L. et al., Eur J Appl Physiol 2000;81(3):188-196

Frequently asked questions

What power should I ride 30/30 intervals at?

At your MAP, estimated here at 120–130% of FTP: 240 to 260 W for an FTP of 200 W, 300 to 325 W for 250 W, 360 to 390 W for 300 W. The 30-second recoveries are ridden at 55–65% of FTP. If you know your measured MAP, aim for 100 to 110% of it.

ERG or resistance mode for 30/30s?

Resistance or slope mode, ideally. In ERG the trainer takes several seconds to reach each new target, and over 30 seconds that's a fair chunk of the effort lost. In resistance mode you change gear or cadence to set the power yourself, and it's right from the first second.

30/30 or 30/15: which should I choose?

30/30s to begin with: a recovery as long as the effort lets you hold your power through the whole set. Rønnestad's 30/15s cut the recovery to 15 seconds: harder, and more time close to your VO₂max. Move to the second once the first becomes routine.

How many sets of 30/30 should I do?

Two sets of 10, so 10 minutes at MAP, to start with. Once all twenty reps go by at the same power, add a third set before shortening the recovery. If the second set falls apart, stick with sets of 8 for a while.

Take it up a level with Wattson

An intuitive workout editor to build cycling and running sessions in no time, then sync them to your watch or bike computer: Wahoo, Garmin, Suunto or Coros.