VO2 max intervals done right: intensity, recovery, mistakes

What VO2 max actually is

VO2 max is the speed at which your body consumes maximum oxygen. It's a max-sustainable intensity zone typically 4 to 8 minutes. The session works at 95-105% of that speed to stimulate VO2 max growth.

To know it: half-Cooper test (6 min max), VAMEVAL (track), or simpler, a 5×4 min session at max sustainable pace. Average speed gives VO2 max velocity.

Short or long intervals

Short intervals: 30 sec to 1 min 30 per rep, 8 to 15 reps. Short recovery (equal to work time). Best for peak aerobic power.

Long intervals: 2 to 5 min per rep, 4 to 8 reps. Recovery half of work time. Best for the ability to hold high intensity (10K, half).

• Short: 10×400 m, 1 min rest, or 12×(30/30)
• Medium: 6-8×1000 m, 2 min rest
• Long: 5×1500 m, 3 min rest, or 4×4 min, 2 min rest

Recovery: a classic trap

Recovery too short: you can't hold target pace, the session loses its point. Recovery too long: HR drops between reps, you're training discontinuously.

Simple rule: recovery should let you hold target pace on the last rep. If you crack earlier, lengthen recovery or cut reps.

Mistakes that ruin the session

Mistake #1: running the first rep at 110% and exploding on the last. Every rep must be homogeneous. Mistake #2: 2 VO2 sessions per week. One is usually enough, except short 10K-focused cycles (with 48h minimum between them).

Mistake #3: skipping the warmup (20 min easy + 4-6×100 m strides). Starting VO2 cold = guaranteed muscle injury.