'Project 90' - Mary's Training Routine for a sub 1:30 half marathon - This Messy Happy

Aug 13, 2025

This is a quick summary of ‘Project 90’ - Mary’s Training Routine for a sub 1:30 half marathon from This Messy Happy. It’s a great watch — we’re breaking it down so you can try the workout today. Be sure to check out the full video for all the details.

Key Points

Polarised training: most weeks consist of three core run types – low‑intensity long runs, a steady‑state/tempo run, and a high‑intensity interval session.
Long runs should be well below race pace to build endurance without excess fatigue.
Tempo run mimics the half‑marathon target pace (about 6:52 min/mile or 4:18 min/km) for a sustained effort.
Speed work focuses on short, hard intervals at 5K pace to boost VO₂max and leg turnover.
Include technique drills before runs to improve form and speed.
Mary documents every session on Instagram; you can follow along and adapt the plan to your own paces.

Workout Example – 5K Pyramid Interval

Warm‑up: 10‑15 min easy jog + drills

Intervals (5 km total, ~50‑55 min):
- 1 min @ 5K pace, 0:30 min easy jog
- 2 min @ 5K pace, 1 min easy jog
- 3 min @ 5K pace, 1:30 min easy jog
- 4 min @ 5K pace, 2 min easy jog
- 5 min @ 5K pace, 2:30 min easy jog
- 4 min @ 5K pace, 2 min easy jog
- 3 min @ 5K pace, 1:30 min easy jog
- 2 min @ 5K pace, 1 min easy jog
- 1 min @ 5K pace, 0:30 min easy jog
Cool‑down: 10 min easy jog

Adjust the paces to match your own 5K speed and use the rest intervals as half the work time.

Closing Note Give Mary’s polarised plan a try—swap the paces to fit your current fitness in the Pacing app, keep the weekly mix of easy long runs, a tempo effort, and a hard interval day, and watch your half‑marathon speed climb. Good luck, and enjoy the journey!