What Happens When You Ask AI to Rate Your London Marathon Training Block?

It’s the day before THE day — London Marathon day. Not just any race... this is THE London Marathon, one of the BIGGEST and BEST in the world.

As I’m sitting here with my feet up (trying my best to actually "rest"), I find myself thinking back over the whole London Marathon Training Block. Four months of early mornings, long runs, speed sessions, and a questionable amount of gels. And honestly? I couldn't have asked for it to go better — everything executed to plan, no injuries, no illnesses (praise the running gods).

Then — because taper week boredom is real — I started wondering: What would AI make of all this London Marathon training?

So, naturally, I exported my Garmin data, uploaded it to ChatGPT, and asked it to summarise the whole thing — week-by-week, long runs, speed sessions, the lot.

So if you’re into running stats, training plans, or just fancy seeing what four months of early mornings and sore legs looks like... here’s the full breakdown.....

London Marathon Training Block Breakdown

Week 1-4: Build Phase

• Mileage: 75–79 km per week

• Long Runs:

  • Week 2: 17.05 km (Total Week: 75.16 km)

  • Week 3: 22.02 km (Sunday Long Run) (Total Week: 73.22 km)

  • Week 4: 26.50 km (Saturday Long Run) (Total Week: 78.99 km)

  • Week 5: 28.52 km (Saturday Steady Long Run) (Total Week: 78.07 km)

Overview:

• Built a strong aerobic base, gradually increasing both long run distance and total weekly mileage.

• Most runs were steady aerobic, with midweek featuring aerobic work and early intervals (e.g., 400m sessions).

• Nearly all runs early morning, setting up race-day timing habits.

• Long runs were run at relaxed, controlled effort (5:11–5:42/km pace).

  
  

Solid aerobic foundation. Smart build. Morning consistency locked in.

Week 5-8: Increase Phase

• Mileage: 48–100 km per week

• Long Runs:

  • Week 6: 11.06 km (Recovery focus) (Total Week: 48.74 km)

  • Week 7: 21.21 km (🏅 Headcorn Half Marathon, 1:32:43, 4:22/km) (Total Week: 82.42 km)

  • Week 8: 30.03 km (Friday Long Run) (Total Week: 71.09 km)

  • Week 9: 30.02 km (LR Friday - Big week!) (Total Week: 100.22 km)

    
    

Overview:

• Smart recovery week at the start before launching into the hardest block so far.

• Headcorn Half Marathon: excellent sub-1:33 half, showing early race fitness.

• Back-to-back 30 km long runs built marathon-specific endurance.

• Continued prioritization of morning running, especially long efforts at marathon effort.

Race sharpened. Big mileage achieved. Long runs pushing distance limits.

Week 9-12: Peak Phase

• Mileage: 77–103 km per week

• Long Runs:

  • Week 10: 21.14 km (🏅 Paddock Wood Half Marathon, 4:29/km) (Total Week: 77.29 km)

  • Week 11: 34.17 km (Friday Long Run) (Total Week: 90.29 km)

  • Week 12: 36.02 km (Massive Friday Long Run) (Total Week: 102.96 km)

  • Week 13: 38.51 km (Longest Run!) (Total Week: 87.04 km)

Overview:

• Second race, Paddock Wood Half Marathon — controlled faster-than-marathon pace sharpening.

• Huge back-to-back long runs (34–38 km) — incredibly strong for building late-race stamina.

• Long runs transitioned into progression runs: steady start ➔ faster finishes at marathon pace (4:50–5:00/km).

• Recovery runs mixed midweek to manage cumulative fatigue.

Peak marathon conditioning achieved. Stamina at all-time high.

Week 12-16: Peak ➔ Taper Phase

• Mileage: 85 ➔ 58 ➔ 27 km

• Long Runs:

  • Week 14: 34.11 km (Strong final long run) (Total Week: 85.96 km)

  • Week 15: 25.5 km (Taper begins) (Total Week: 87.17 km)

  • Week 16: 16.11 km (Sharpener long run) (Total Week: 58.26 km)

  • Week 17: 10.05 km (Race week!) (Total Week: 27.19 km)

Overview:

• Final major long run (34 km) positioned perfectly 3 weeks out.

• Smooth transition from big long runs to shorter marathon-pace simulations.

• Fatigue melted away without losing sharpness — ready for race conditions.

• Light maintenance runs in the final week, preserving leg freshness.

  
  

***Elite-level taper. Fitness maintained. Freshness maximized***

Full Training Trends

Category	Trend	Notes
Time of Day	Morning dominant	~80%+ of runs before 10am — excellent marathon prep.
Speed Sessions	5 key efforts	Short intervals, faster aerobic tempos.
Easy/Recovery Runs	~10 easy runs	Actively managed fatigue and avoided burnout.
Races	2 half marathons	Integrated beautifully into your build (race pace controlled).
Rest/Recovery	Active rest weeks	Light runs rather than total rest — kept rhythm alive.
Long Run Progression	17 ➔ 22 ➔ 26 ➔ 28 ➔ 30 ➔ 34 ➔ 36 ➔ 38 km	Perfect textbook build of endurance.

Final Race Readiness Verdict

✅ Big aerobic engine.

✅ Properly developed marathon-specific endurance.

✅ Sharp speed from race efforts.

✅ Strong morning habits and great mental prep.

✅ Textbook taper — ready to peak.

***You’re completely prepared.Trust your training. Trust your build. Trust yourself*** London 2025 is YOURS. 🚀🏁

I'll remember that 20 miles in. Oh well, that’s it. The work is done. The maranoia is (mostly) over.

Just need to get some sleep tonight... and then the party begins! 🎉🏃‍♂️