Your watch knows your VO2 max. This app makes it higher.

Norwegian 4x4. Tabata. HIIT 30/30. And more.

PEAKVO2 workout list showing Norwegian 4x4, Tabata, and other interval protocols

Pick your protocol

Norwegian 4x438 min
Tabata14 min
HIIT 30/3025 min
Billat 30/3025 min
Ronnestad 30/1538 min
VO2 Max 3x327 min
VO2 Max 5x339 min
Tempo Run40 min

Norwegian 4x4 protocol detail showing warm-up, work, and recovery phases

Warm-up phase with orange screen

Warm-up

Work phase with red screen

Work

Recovery phase with blue screen

Recovery

See your training add up

VO2 max trend: Watch your estimated VO2 max climb as you stay consistent week after week.
Year in review: A heatmap of every session. Gaps are obvious. Streaks are satisfying.
All your workouts count: PEAKVO2 tracks sessions from other apps too, so your full training volume shows up in one place.

PEAKVO2 activity detail showing heart rate and workout summary

No subscription. Ever.

3 workouts free. Then one payment to unlock everything. No recurring charges. No feature gates. You own it.

From the blog

Runner on an outdoor path through green fields

The Norwegian 4x4 Protocol

A complete guide to the science-backed interval workout proven to increase VO2 max.

Apple Watch showing running workout data on a wrist

Improve Your Apple Watch Cardio Fitness Score

What your score means, why it might be low, and the fastest way to raise it.

Find a VO2 max testing lab

Browse our curated directory of professional testing labs worldwide.

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Test your VO2 max first

BeepRunner runs the official 20m beep test and Cooper test on your iPhone — with instant VO2 max estimation.

BeepRunner home screen

BeepRunner test result with VO2 max

Learn more about BeepRunner →

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Questions? [email protected]