01
The moderate middle
Most people run their easy days too hard and their hard days too easy. Your coach programs strict polarized training, keeping eighty percent of your week easy enough to hold a conversation.
For adults and runners: Build a bigger aerobic engine on mostly easy days.
This is a VO2 max training program for beginners and runners looking to build their aerobic base. Your AI coach programs five polarized sessions a week, balancing easy miles with true interval work.
VO2 Max Builder is $16.99/mo · cancel anytime · secure checkout by Stripe
- training days a week
- 5
- per session
- 15–70min
- meals a day
- 4
- between deloads
- 4wk
VO2 Max Builder your coach · online
Today · Monday
Aerobic Base
15–70 min · from your plan
You: I slept terribly and my resting heart rate is up. Can I swap today's intervals with tomorrow?
Your coach: Done. Tomorrow's easy 30-minute spin and strength mini move to today, and the threshold intervals move to tomorrow. Keep today truly easy.
Plan updated · confirmed in chat
The problem
Why generic running plans fail
02
Guessing your zones
Generic plans use age-based math that gets it wrong. In week one, your Monday easy run becomes a 12-minute field test, and your coach turns the result into zones in chat.
03
Static fueling plans
Eating the same amount on a heavy interval day and a rest day leaves you under-fueled. Your coach adjusts your four daily meals to match that day's specific training load.
The method
How VO2 Max Builder works
01
Volume before intensity
Your coach builds your aerobic base first. Your long Saturday session's note tells you to add ten minutes a week toward ninety, and interval pace waits until easy days are truly easy.
RuleAdd Zone 2 time before you add interval pace
02
Monitored recovery
The coach reads your health data daily. If your resting heart rate spikes or you report high fatigue, it programs a lighter week to let you recover.
RuleElevated resting heart rate triggers a lighter week.
03
Load-matched fueling
Hard days require more carbohydrates. Your coach programs exactly what to eat across your four meals, scaling a daily protein target to your bodyweight.
RuleFour meals a day matched to training load.
04
Five polarized sessions
The plan schedules three easy days, one interval session, and one long builder. The interval and long days run from a warm-up to a cool-down.
RuleSessions range from fifteen to seventy minutes.
Your week
A typical training week
Ask your coach in chat to move any session to a day that fits your week.
- Mon: Aerobic Base(Train)
- Tue: Threshold Intervals(Train)
- Wed: Zone 2 Recovery(Train)
- Thu: Mobility and Heart-Rate Review(Active)
- Fri: Zone 2 Cadence(Train)
- Sat: Long Zone 2(Train)
- Sun: Walk and Weekly Zone Audit(Active)
Built to adapt
A plan that moves when your week does.
It reads your recovery
Connect Apple Health or Health Connect. When sleep, HRV or resting heart rate say you are under-recovered, today's session gets lighter. Planned deloads follow your coach's schedule, and you can ask for one in chat.
Chat that changes the plan
Travelling, sore, short on time, missed a meal: tell your coach at any hour. It rebuilds the week or re-portions the day, and confirms the change in chat.
Check-ins it acts on
Daily check-ins and progress photos go to your coach, and your plan is adjusted from what actually happened, not what was scheduled.
Is it for you
Who this coach is built for.
Built for
- Beginners starting in the bottom fitness bracket
- Runners chasing faster race times
- Adults returning after time off
Pick another coach if
- Athletes wanting a race-specific marathon build
- Anyone currently injured or needing a return-to-run plan
Pricing
One coach. One price. No contract.
Create your account, check out with Stripe and answer a one-minute intake. VO2 Max Builder writes your first plan before you sign in. Month to month; cancel in a tap.
VO2 Max Builder
$16.99/ month
- A week-by-week training plan, built from your intake
- A nutrition plan, with food swaps
- 24/7 chat that changes the plan, not just answers
- Apple Health and Health Connect sync
- Daily check-ins and progress photos
- Progression and deloads handled for you
Secure checkout by Stripe · cancel anytime
Questions
Straight answers.
Something else? Ask your coach in chat once you are in. It answers at any hour.
How do I know my heart rate zones?
Monday's note tells you to swap week one's easy run for a 12-minute or 5K field test. Share the result with your coach in chat to set your zones, and repeat the test every six weeks on the same course.
What equipment do I need for this?
You need a way to track your heart rate, like a watch or chest strap, and a place to run or cycle. The strength mini-sessions require minimal equipment.
Do I really need to train five days a week?
Yes, the method needs the volume. Your five sessions run up to 70 minutes, and three of them are very easy Zone 2 days that build your base.
What happens if I miss a meal or a workout?
Tell your coach in the chat. A missed session is dropped, not doubled up, and you can move an upcoming one to another day. Your coach will re-portion your remaining meals to keep you fueled.
Will this give me a marathon training plan?
No. This is an engine-building block focused purely on aerobic capacity and VO2 max development. It is not a race-specific build for a marathon or triathlon.
What do I get for free?
Your account is free — browse coaches, explore the app, and connect with a coach. Each AI coach is a monthly subscription (priced by coach); cancel anytime in a tap.
Is this a real coach or an AI?
It's an AI coach built on a real training methodology for this exact niche. It writes your plans, adjusts them from your check-ins and progress, and answers questions any time — no waiting for office hours.
What if it doesn't fit my situation?
Your plan is built from YOUR intake — goals, schedule, equipment, injuries, preferences. If something doesn't fit, tell your coach in chat and it adjusts. And you can cancel any subscription anytime.
What happens to my data?
Your data stays yours. We never sell it, and you can export or delete your account at any time. See our Privacy Policy for the details.
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