How to train your cardiovascular fitness | Peter Attia - Peter Attia MD

Aug 13, 2025

Intro: This is a quick summary of “How to train your cardiovascular fitness” from Peter Attia MD. It’s a great watch — we’re breaking it down so you can try the workout today. Be sure to check out the full video for all the details.

Key Points:

Cardio fitness can be visualized as a triangle: the base is low‑intensity Zone 2 work, the peak is high‑intensity VO₂ max work. Aim for an 80 % Zone 2 / 20 % VO₂ max split (elite athletes often hit 90/10).
If you can only train 4–5 hours per week, allocate ~3.5 hours to steady‑state Zone 2 and ~0.5–1 hour to VO₂ max intervals.
Zone 2 sessions should be 30–60 minutes at a heart‑rate or RPE that feels comfortably easy (you can still talk). Split them across 2–4 days to keep each bout 30–45 min.
VO₂ max work is best done in 3–8 minute intervals (e.g., 4 min hard, 4 min easy) on a hill, bike, treadmill, rowing, or stair‑climber. Warm‑up ~10 min before the hard effort.
Consistency matters more than a single long session; aim for at least 30 min of continuous Zone 2 each workout.

Workout Example (Weekly Plan):

Monday: 90 min lower‑body strength + stability (optional).
Tuesday: 45‑60 min Zone 2 (bike, treadmill, or easy run). Follow with 30 min stability work.
Wednesday: 90 min upper‑body strength + stability.
Thursday: Repeat Tuesday Zone 2 session.
Friday: Repeat Monday strength day.
Saturday: 45‑60 min Zone 2 in the morning; afternoon upper‑body strength.
Sunday: Zone 2 (30 min) followed by VO₂ max intervals – e.g., 4 min hard uphill (or high‑intensity bike) / 4 min easy recovery × 4‑6 repeats.

If you only have 15 min per day, combine two 30‑min Zone 2 blocks on separate days or do a single 30‑min session plus a short VO₂ max interval.

Practical Tips:

Use a heart‑rate monitor or RPE to stay in Zone 2; lactate‑based or perceived effort is more reliable than raw HR alone.
For VO₂ max, choose a modality you can sustain ≥3 min at high effort (hill repeats, air‑bike, rowing).
Warm‑up 10 min before VO₂ max work; aim for a total of ~1 hour of high‑intensity work per week.
Track your sessions in the Pacing app and adjust paces to match your personal heart‑rate zones.

Closing Note: Try this 80/20 cardio pyramid this week, tweak the durations to fit your schedule, and watch your cardiovascular fitness rise. Feel free to customize the paces in the Pacing app to suit your own thresholds—happy training!