New Year, New Zones: Build an 80/20 Plan With Your VO₂ and Threshold Data
You can make big endurance gains this year by pairing laboratory-measured zones with a simple weekly split: 80 percent easy and 20 percent hard. With VO₂ and threshold testing, your ventilatory thresholds (VT1 and VT2) give you precise anchors for easy, moderate, and hard training so you stop guessing and start adapting.
This guide shows you how to translate your data into a clear plan, avoid common mistakes, and apply weekly templates for running, cycling, and triathlon.
What the 80/20 Rule Really Means
The 80/20 rule is a training distribution, not a single workout.
80% of your weekly training time should be below VT1 (easy aerobic work)
20% of your weekly time should be at or above VT2 (threshold and VO₂ max work)
Below VT1 your breathing is relaxed and conversational. Above VT2 breathing is hard, efforts are time-limited, and this is where VO₂ max and threshold adaptations are stimulated.
This polarized structure:
Allows higher weekly volume
Prevents burnout
Focuses intensity where it actually drives improvement
Can you increase VO₂ max after 50?
Yes. When intensity is dosed correctly, recovery is respected, and strength is maintained, athletes over 50 often see meaningful gains within the first 8–12 weeks.
Map VT1 and VT2 to Training Zones
Your ventilatory thresholds come from gas-exchange testing during graded exercise. They create three practical training buckets:
Easy – Below VT1
Aerobic base
Low lactate
Fat-dominant metabolism
Full-sentence breathing
Used for most mileage, drills, and recovery
Moderate – Between VT1 and VT2
Tempo and steady state
Feels “comfortably hard”
Useful sparingly for race-specific prep
Easy to overuse
Hard – At or Above VT2
Threshold repeats
VO₂ max intervals
Hill reps and sprints
Breathing is labored and sets require recovery
Once you have VO₂ max, VT1, VT2, and max heart rate, you can build heart-rate, pace, and power zones with precision.
Important: Always use discipline-specific zones. Run heart rate does not translate to the bike.
Why Lab Testing Beats Guesswork
Field formulas and talk tests help, but lab testing removes error.
A cardiopulmonary exercise test provides:
VO₂ max
VT1
VT2
True maximal heart rate
This lets you anchor all training to physiology rather than estimates.
For runners: the most useful performance test combines VO₂, VT1, VT2, and threshold pace.
For endurance athletes: a VO₂ test plus a 20–40 minute threshold assessment provides the clearest picture of sustainable performance.
Avoid the Grey Zone Trap
The biggest mistake is spending too much time between VT1 and VT2.
It feels productive. It feels strong.
But it breaks the 80/20 model and stalls progress.
Signs you are training in the grey zone:
You cannot speak in full sentences on “easy” days
Heart rate drifts up early in workouts
Legs feel heavy despite moderate training
Mood, sleep, or motivation decline
Protect easy days. Make hard days truly hard.
Weekly 80/20 Training Templates
Always warm up and cool down below VT1.
Runners (5 sessions/week)
3 easy runs: 30–60 minutes below VT1
1 threshold workout: 3–5 × 8 minutes just below VT2
1 VO₂ workout: 6–10 × 2–3 minutes at or above VT2
Target: 80% easy, 20% hard
Cyclists (4–5 rides/week)
2–3 endurance rides: 60–180 minutes below VT1
1 threshold ride: 3 × 12–20 minutes near VT2
1 VO₂ or anaerobic ride: 1–5 minute repeats above VT2
If you ride long on weekends, stay aerobic and add short climbs only if you preserve the 80/20 split.
Triathletes
Swim: 2–3 sessions, mostly below VT1 with one threshold set
Bike: 2–3 sessions, one hard interval day
Run: 2–4 sessions, one threshold or VO₂ day
Distribute intensity across sports so the total week still hits 80% easy / 20% hard.
Progression and Recovery
Hold each training block for 3–4 weeks, then progress one variable:
Increase easy volume
Add reps to hard sessions
Lengthen intervals
Maintain at least one full rest or very light day each week.
If performance drops, remove moderate work — not easy volume.
From Test to Training Plan
For accurate zones and a personalized plan:
Ventilatory threshold testing in Northville establishes VT1, VT2, and max HR
Professional VO₂ max testing in Northville gives full physiological profiling in one visit
Cyclists should use bike-specific VO₂ testing to avoid run-to-bike zone mismatch
January Reset
January is the ideal time to:
Reset zones
Align your 80/20 split
Build race-specific blocks
Most tests take about an hour and include a full interpretation so you leave knowing exactly how to train.
Summary
Use VO₂, VT1, and VT2 to anchor your three training zones.
Train 80% below VT1 and 20% at or above VT2.
Avoid the grey zone.
Follow simple, discipline-specific templates.
You can improve VO₂ max at any age when intensity is prescribed correctly.
If you want a clean start to the year, schedule VO₂ and threshold testing and build an 80/20 plan you can follow with confidence.
