What is VO2sday?

VO2sday Micro Races are a weekly series of short, intense races designed to deliver a true VO2 max workout in an engaging and competitive setting. Instead of one long race where most riders sit in then sprint at the end, this is a set of 5 brief, all-out efforts with recovery in between, just like a classic VO2 max interval session.

The twist: races are a specific duration (usually 4 minutes), not a specific distance. The goal is simple, but not easy: cover as much distance as you can before the clock runs out. The general classification is based on your cumulative distance across all 5 races.

The format

• Five short races in under an hour, five hard VO2 max efforts.
• Each race is time-based (usually four minutes); the most distance wins.
• Roughly ten minutes between race starts means ~6 minutes of recovery.
• A mix of flat, climbing, rolling, and downhill courses each week.
• Compound-score categories (A/B/C/D) based on your five-minute power and weight.
• Mass start with drafting disabled, so each race is effectively a time trial.
• Three time slots (“Zones”) each week so riders around the world can compete.