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Aerobic

170 min

Medium intensity

The Flatline Base Builder

Teach a rider to hold clean, steady power: three blocks of 30 minutes at the low end of zone 2 and 15 minutes at the high end, with cadence targets, so the difference between the two is felt as well as measured.

Thanh Vo

Coach

Stimulus

Aerobic

Duration

170 min

Intensity

Moderate

RPE

4 / 10

Level

Beginner

Best ridden

Outdoors

The session

The workout

Written as a share of critical power, so it fits every rider. In Vekta it becomes your watts, with the W′ cost shown before you ride.

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Free, one step

Unlock the full workout

Every interval and every target, right here on this page and in your inbox.

By unlocking you subscribe to Vekta's workout emails. Unsubscribe any time.

The Flatline Base Builder

Thanh Vo

Warm up 10 min @ 50-55% CP Block 1 30 min @ 55-60% CP, 85-95 rpm 15 min @ 70% CP, 85-95 rpm 5 min @ 45-50% CP Block 2 30 min @ 55-60% CP, 85-95 rpm 15 min @ 70% CP, 85-95 rpm 5 min @ 45-50% CP Block 3 30 min @ 55-60% CP, 85-95 rpm 15 min @ 70% CP, 85-95 rpm 5 min @ 45-50% CP Cool down 10 min @ 45-50% CP

Next step

Ride The Flatline Base Builder in Vekta

Scaled to your CP and W′ automatically, synced to your device, with the cost shown before you ride it. Free for 14 days.

Start 14-Day Free Trial

Already on Vekta? Open the app

Coaching instead? Switch to the coach view

Next step

Ride The Flatline Base Builder in Vekta

Scaled to your CP and W′ automatically, synced to your device, with the cost shown before you ride it. Free for 14 days.

Start 14-Day Free Trial

Already on Vekta? Open the app

Coaching instead? Switch to the coach view

Next step

Ride The Flatline Base Builder in Vekta

Scaled to your CP and W′ automatically, synced to your device, with the cost shown before you ride it. Free for 14 days.

Start 14-Day Free Trial

Already on Vekta? Open the app

Coaching instead? Switch to the coach view

Next step

Prescribe The Flatline Base Builder to your athletes

Paste the structure into the AI Workout Builder and it becomes a session in each athlete’s zones, synced to their device. Free for coaches.

Create free account

Book a demo

Switch to the athlete view

Next step

Prescribe The Flatline Base Builder to your athletes

Paste the structure into the AI Workout Builder and it becomes a session in each athlete’s zones, synced to their device. Free for coaches.

Create free account

Book a demo

Switch to the athlete view

Next step

Prescribe The Flatline Base Builder to your athletes

Paste the structure into the AI Workout Builder and it becomes a session in each athlete’s zones, synced to their device. Free for coaches.

Create free account

Book a demo

Switch to the athlete view

Why this workout

Thanh Vo on this workout

Thanh Vo

"I often get new influxes of young riders who come to me having never trained with power meters, so many of them do not know how to hold steady power. In this session I break a long endurance ride down into manageable blocks with clear power and cadence targets. This teaches my rider to hold clean and steady efforts that will become the basis for their development. Riding the low end and then the high end of Zone 2 back to back also helps the rider feel the difference between the two. Feeling the effort and establishing that mind-body connection is an important pillar that I emphasise early on, so that harder efforts become easier to coach. Hold a steady cadence the whole way through and keep freewheeling to a minimum. The aim is a power line that is as flat as possible."

"I often get new influxes of young riders who come to me having never trained with power meters, so many of them do not know how to hold steady power. In this session I break a long endurance ride down into manageable blocks with clear power and cadence targets. This teaches my rider to hold clean and steady efforts that will become the basis for their development. Riding the low end and then the high end of Zone 2 back to back also helps the rider feel the difference between the two. Feeling the effort and establishing that mind-body connection is an important pillar that I emphasise early on, so that harder efforts become easier to coach. Hold a steady cadence the whole way through and keep freewheeling to a minimum. The aim is a power line that is as flat as possible."

— Thanh Vo

Instagram ↗

The breakdown

Inside the workout

Thanh Vo built this for riders arriving with a power meter and no idea how to hold steady power. A long endurance ride broken into blocks with clear power and cadence targets teaches clean, steady effort, and riding the low end of zone 2 then the high end back to back teaches the difference between them.

Three identical blocks: thirty minutes at 55–60% of CP, fifteen at 70%, five easy, all at 85–95 rpm. Nothing about it is hard. The value is in holding the numbers flat for thirty minutes at a time, which is the foundation every harder session is built on later.

Vekta's zones tab shows time in each band and the power trace shows how flat it really was; the aerobic decoupling of heart rate against power across the three blocks is a useful first look at a new rider's base.

A base-phase ride, weekly, outdoors on flat roads. The mind-body connection Thanh Vo describes is the real output.

Aerobic

Stimulus

Beginner

Workout level

Outdoors

Best ridden

Road,

DISCIPLINE

The stimulus

Aerobic, explained

Sustained aerobic power below VO2 max: the engine between endurance and threshold.

What it is

Intervals and blocks at 80–100% of critical power, longer than VO2 max efforts and harder than tempo, often with torque or cadence work built in. Step-downs, long tempo-to-threshold progressions and torque blocks belong here.

Why it matters

This is where aerobic capacity is converted into usable power: the ability to hold a high fraction of VO2 max for long periods. It is the stimulus behind time trialling, long climbs and the last hour of a road race.

NeuromuscularPeak power, Pmax

AnaerobicW′ capacity

VO2 MaxAerobic ceiling

Lactate ClearanceRecovery under load

ThresholdCritical power, CP

TempoSustainable pace

AerobicEfficiency

DurabilityFatigue resistance

Heat TrainingHeat tolerance

TestSets CP and W′

If you ride it

These sessions are long and demanding but not maximal. Pacing is the skill: the target is even power across the block, and the last minutes should feel hard but possible.

If you coach it

Aerobic sessions are the bridge in a block: enough intensity to hold the ceiling gained from VO2 work, enough volume to keep the base. Watch the intensity score in Vekta; these sessions should score high on volume and moderate on intensity.

In Vekta

Personalised to CP in Vekta, with the intensity graph showing where the session bites. Afterwards the session is classified by its dominant stimulus and compared with the athlete's previous aerobic sessions.

Common questions

Is aerobic the same as endurance?

What cadence?

How does this differ from sweet spot?

Go deeper