About PEAKVO2
The VO2 max interval training app for iPhone and Apple Watch, and the evidence-based training resource behind it.
What PEAKVO2 Is
PEAKVO2 is a VO2 max interval training app for iPhone and Apple Watch. It runs the interval protocols with the strongest research behind them, the Norwegian 4x4, Tabata, HIIT 30/30, REHIT, and more, with automatic phase changes and real-time guidance on your wrist, and it includes built-in beep test and Cooper test field tests so you can measure your VO2 max and then train it up in one place.
Alongside the app, this site publishes evidence-based training content, a set of free training tools (VO2 max, max heart rate, and zone 2 calculators, plus interval timers), and a directory of VO2 max testing labs worldwide.
Who Builds It
PEAKVO2 is built by Cristian Serb. I built it because I was doing the Norwegian 4x4 myself and wanted the timing handled on my wrist so I could just train. I took my own VO2 max from about 41 to 51 with it, and the app and this site grew out of that. I write the articles here, and I care about getting the science right rather than repeating fitness folklore.
How the Content Is Researched
Every training claim on this site is tied to a source. The protocols and numbers come from peer-reviewed research (linked to PubMed), and the VO2 max norms come from the American College of Sports Medicine's Guidelines and The Cooper Institute's data, not from round numbers passed around online. Where the evidence is weak or contested, the articles say so plainly. Articles carry a visible last-updated date and are revised when the research or the products change.
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Questions or corrections: [email protected].