#WOTW: Holly Archer Running Series

Session 2: VO₂ Max Work – Sharp and Fast

(Missed Session One? Find It Here)

Why it matters:
This is the session that lifts your ceiling. VO₂ max training improves your ability to use oxygen efficiently at high intensities—key for both runners and HYROX athletes. It’s the zone that builds speed endurance, mental grit, and race sharpness.

The Session

Warm-up:
10–15 minutes easy jog + drills + strides

Main Set:
16–20 x 400m at faster than your 5K pace
Recovery: 45–60 seconds rest or slow jog
Beginners can start with 12–16 reps; experienced runners can push to 20

Cool-down:
10 minutes easy jog

Top Tip:
The first few reps feel fine—don’t get carried away. The real work begins in the last five reps. Keep your form strong, maintain posture, and stay consistent. If you’re training for HYROX, this type of session is brilliant for building anaerobic efficiency and resilience under fatigue.