There’s something psychologically satisfying about an interval session where the repetitions keep getting shorter.
Unfortunately, that doesn’t necessarily mean they keep getting easier.
Matt Bottrill’s Descending Intervals starts with four-minute Level V efforts before progressing through three-minute and two-minute repetitions and finishing with a final one-minute effort.
As the duration decreases, the challenge changes. Early in the workout, you need to control your effort well enough to complete repeated four-minute intervals. Later, when fatigue has accumulated but the repetitions become shorter, the goal is to continue producing quality Level V power rather than simply surviving to the end.
It’s a substantial VO₂ Max workout with 30 minutes of Level V riding spread across ten repetitions.
The structure is simple.
Executing it well is another matter.
Start controlled. Keep the quality. Finish strong.
Session Inspiration
This workout was originally inspired by cycling coach Matt Bottrill.
When I first published the session in 2020, the inspiration came from an article featuring Bottrill on Triathlete.com. The original workout uses descending repetition durations while keeping the hard efforts at Level V. To read the original article click here.
I like the format because it provides a substantial amount of high-intensity work without asking you to repeat exactly the same interval ten times.
Instead, the session evolves as fatigue accumulates.
You start with the longest efforts.
Then they gradually get shorter.
By the time you reach the final one-minute repetition, you’ve already accumulated 29 minutes at Level V.
That last minute counts.
Today’s Workout
Warm-Up
- 15min Level II
Ride steadily at Level II. Use the warm-up to gradually prepare your legs and cardiovascular system for the harder work ahead.
You have plenty of Level V riding coming, so there’s no benefit in making the warm-up harder than prescribed.
Main Set
4x:
- 4min Level V
- 4min Level II Rest Interval
Then 3x:
- 3min Level V
- 3min Level II Rest Interval
Then 2x:
- 2min Level V
- 2min Level II Rest Interval
Finish with:
- 1min Level V
Move directly into the cool-down after the final one-minute repetition.
Cool-Down
- 15min Level II
Allow your effort to settle while continuing to turn the legs over comfortably.
Stretching
- 10min stretching
Total riding duration: 89 minutes
The workout contains 30 minutes at Level V, divided across ten hard repetitions.
Why You’re Doing This Session
Level V training targets the upper end of your aerobic system and places a substantial demand on your ability to produce and repeatedly reproduce high aerobic power.
But there’s another element I particularly like about this workout:
the interval duration keeps changing.
Four minutes at Level V requires a different approach from one minute at Level V.
During the opening set, patience matters. If you attack the first four-minute repetition as though it’s the only interval you’re doing, the remaining workout can become very difficult very quickly.
The three-minute repetitions remain long enough that pacing still matters, but they can feel more manageable after completing the opening set.
Then you reach the two-minute efforts.
Finally, there’s only one minute remaining.
The intervals become shorter—but you become increasingly fatigued.
That gives the workout its character.
What You Should Focus On
The most important goal is repeatable Level V quality.
Don’t judge the workout by the highest power number you can produce during the first repetition.
Judge it by how consistently you can execute the complete session.
During the four-minute repetitions, establish Level V promptly without massively overshooting your target. Settle into the effort and concentrate on maintaining consistent power.
As the repetitions become shorter, resist the temptation to turn them into maximal efforts.
They are still Level V intervals.
The decreasing duration should help you continue producing quality work despite the fatigue you’ve accumulated—not give you permission to sprint every remaining repetition.
Your upper body should remain controlled. Keep your shoulders, arms and hands relaxed and concentrate on maintaining a smooth pedal stroke even as the effort becomes uncomfortable.
The objective is controlled high-intensity cycling, not simply generating the biggest numbers possible.
Common Mistakes to Avoid
Starting the first set too hard.
Four four-minute Level V repetitions represent 16 minutes of quality work before you’ve even reached the three-minute intervals. Going too hard early can compromise everything that follows.
Treating every repetition like a test.
You’re training your ability to repeat Level V efforts. You don’t need a personal best during every interval.
Increasing the intensity just because the repetitions get shorter.
Unless your individual prescription says otherwise, Level V remains Level V. Shorter doesn’t automatically mean harder.
Riding the Rest Intervals too hard.
Your Level II recoveries are there to help you reproduce quality during the next repetition. Don’t turn them into extra work.
Giving up on technique when fatigue builds.
The final few repetitions are where good habits matter most. Stay controlled rather than rocking on the bike or fighting the pedals.
Coach Ray’s Tips
Respect the four-minute repetitions
These establish the session.
There’s a lot of work still to come, so aim to finish the fourth four-minute effort knowing you’ve worked hard but can continue producing quality.
Use the Rest Intervals
Keep riding at Level II and let yourself recover.
The purpose isn’t to make the workout continuously hard. It’s to accumulate 30 quality minutes at Level V.
Mentally reset when the duration changes
Rather than thinking about all ten repetitions at once, break the workout into four distinct sections:
4 × 4min → 3 × 3min → 2 × 2min → 1 × 1min.
Complete one block and move on.
That can make a substantial workout much easier to manage mentally.
Don’t sprint the final minute
You’ll probably be pleased when you reach it.
But there’s still a difference between producing a strong Level V effort and turning the final minute into an uncontrolled maximal effort.
Finish with quality.
Who Is This Workout For?
This is a demanding session suited to cyclists and triathletes who already have an appropriate training base and are accustomed to structured high-intensity cycling.
It can be particularly useful when you want to develop VO₂ Max power and your ability to repeat high-intensity efforts.
At 89 minutes of riding with 30 minutes at Level V, however, this is not a small dose of intensity.
Place it appropriately within your training week and allow sufficient recovery around it.
Less experienced athletes—or athletes returning to higher-intensity training—may be better starting with a reduced version rather than attempting all 30 minutes of Level V work immediately.
Ride With Coach Ray on Velocity
If you enjoy structured indoor cycling but would rather have a coach guide you through the workout, you can join me on Velocity.
Velocity gives you access to coach-led video cycling workouts, including live sessions on Tuesday at 6:00 am NZT for 45 minutes or less and Thursday at 6:00 am NZT for approximately an hour, plus the full on-demand workout library whenever it suits your schedule.
You can try Velocity free for 14 days:
Final Thoughts
Matt Bottrill’s Descending Intervals looks friendlier as you work your way down from four-minute efforts to a final one-minute repetition.
Don’t be fooled.
You’ve got 30 minutes of Level V work to accumulate, and the quality of the later repetitions depends heavily on how intelligently you execute the early ones.
Control the opening set. Recover properly between efforts. Keep producing Level V power as the repetitions become shorter.
Then make that final minute count.
Start controlled. Keep the quality. Finish strong.
If you know a cyclist or triathlete who would benefit from this workout, share the article with them so they can give it a go too.