Improve VO2 max with Norwegian 4x4, Tabata, HIIT 30/30, and more.
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3 workouts free. Then one payment to unlock everything. No recurring charges. No feature gates. You own it.
Why it matters more than ever, and how to improve it with interval training at any age.
A complete guide to the science-backed interval workout proven to increase VO2 max.
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BeepRunner runs the official 20m beep test and Cooper test on your iPhone — with instant VO2 max estimation.
PEAKVO2 is an interval training app for iPhone and Apple Watch used by runners, cyclists, and endurance athletes to improve their VO2 max. It includes science-backed protocols like the Norwegian 4x4, Tabata, HIIT 30/30, Billat 30/30, Ronnestad 30/15, and more, with automatic phase transitions and real-time guidance on your wrist.
PEAKVO2 includes eight protocols: Norwegian 4x4 (38 min), Tabata (14 min), HIIT 30/30 (25 min), Billat 30/30 (25 min), Ronnestad 30/15 (38 min), VO2 Max 3x3 (27 min), VO2 Max 5x3 (39 min), and Tempo Run (40 min). Each protocol has built-in warm-up, work, recovery, and cool-down phases.
PEAKVO2 is built specifically for VO2 max interval training and runs directly on Apple Watch, no phone needed. Full-screen color-coded phases tell you whether you're in warm-up, work, or recovery, with automatic transitions and haptic alerts so you never miss a cue.
Yes. PEAKVO2 includes the full Norwegian 4x4 protocol, four 4-minute high-intensity intervals at 90-95% max heart rate, each followed by 3-minute active recovery, with warm-up and cool-down built in. The app handles all the timing so you just run.
PEAKVO2 gives you 3 workouts free. After that, a single one-time purchase unlocks everything, no subscription, no recurring charges, no feature gates. You own it.
PEAKVO2 guides you through research-backed high-intensity interval protocols that are proven to increase VO2 max. The app handles all the timing, automatic phase transitions, haptic alerts, and color-coded screens, so you can focus entirely on effort. It also tracks your VO2 max trend over time so you can see your progress.
Yes. VO2 max is one of the strongest predictors of longevity, and improving it matters at any age. PEAKVO2's protocols are based on percentage of your max heart rate, so intensity scales naturally to your fitness level. The Norwegian 4x4 protocol in particular has been studied in older populations and shown to significantly improve cardiovascular fitness. As with any high-intensity training, consult your doctor before starting.
