Training for a Fast 5k with Runna, Weeks 9-12 - kofuzi

Aug 13, 2025

Intro

This is a quick summary of Training for a Fast 5k with Runna, Weeks 9‑12 from the kofuzi channel. It’s a great watch — we’re breaking it down so you can try the workouts today. Be sure to check out the full video for all the details.

Key Points

Over‑under interval training: alternating fast and “float” (recovery) intervals to build speed and stamina.
Hill sprint sessions each Tuesday (11 × 60‑second hills + 11 × 30‑second hills, later 17 × 60‑second hills, and a final 2 × 8 × 30‑second set) to develop power and leg strength.
Progression long runs with mixed paces (e.g., 6 km easy, 11 km at marathon‑ish effort, 6 km “float”) to teach pacing under fatigue.
Costco run – a low‑stress, bike‑path loop for mental break and easy mileage.
Pyramid workout (400‑600‑800‑1200‑800‑600‑400) in week 11 to replace hill sprints with a fast‑threshold ladder.
Taper in weeks 11‑12: shorter easy runs (≈8 mi) and a modified over‑under 500‑m interval set to keep sharp while reducing volume.

Workout Example – Week 9 Over‑Under 10 km

Warm‑up: 1‑2 km easy jog.
Over‑under intervals: repeat the following 5 times for a total of 10 km:
- 1 km at 7:05 min/mi (fast “on” interval).
- 1 km at 6:30 min/mi (slightly slower than 4 min/km) – the “float” recovery.
Cool‑down: 1 km easy.
Hill sprint day (Tuesday): 11 × 60‑second hill sprints followed by 11 × 30‑second hill sprints (22 sprints total). Rest 90‑120 seconds between reps.
Pyramid (Week 11): 400 m → 600 m → 800 m → 1200 m → 800 m → 600 m → 400 m at threshold pace (around 7:00‑7:30 min/mi). Rest 2 min between each interval.

Closing Note Give these workouts a try, tweak the paces to match your own training zones in the Pacing app, and keep the hill sprints and over‑under intervals in your routine. You’ll feel stronger, faster, and ready for that 5 K PR—good luck and happy running!