I took a running test for VO2max (54.7 mL/min/Kg), Lactate Threshold (79.2%), and Running Economy (220 ml/km/h) at a marathon training studio June 2022. Their estimate for how quickly I could run a marathon was 3:34.

I've never run a marathon. The closest I've done was an open Spartan Race Sprint (a 5km race with obstacles) in 2017. At the time, I placed in the top 6% of participants.

I do high-intensity interval training (HIIT) twice a week for 25 minutes at a time. Ten-minute jog warm-up, followed by three 2-minute all-out runs with 3-minute jogs. I go about 4.3 km during that time.

I'll be doing a 16-week training program, adding a weekly long run increasing up to 32 km a few times, as well as replacing one of my HIIT sessions with a steady tempo run.

Factors against:

👶 Never run a marathon before.

👴 Am over 50.

Only running 3 times weekly.

Factors for:

Been doing 5:2 fasting for a decade. I do my tempo and HIIT while fasted.

Regular sauna bather. I've upped my sauna time to four 25-30 minute sessions weekly.

Disciplined and planning for the marathon according to best practices.

Will carb-load appropriately.

Bought Addidas Adizero Adios Pro 3's, the shoe worn by most 2023 Boston Marathon top 20.

Practicing taking 25g carb energy gels every 4 km.

I'm a health researcher, with my own blog: www.unaging.com

I've registered for the Osaka Marathon on February 25. Will I complete the marathon in less than 3.5 hours?

Conditions: This will resolve YES if I run and finish in 3.5 hours net time or less. If I don't run for personal reasons or don't finish in less than 3.5 hours, it resolves NO. If some force majeure cancels or delays the marathon itself -- earthquake, North Korea attack, whatever -- then I'll terminate the bet as unresolved however that works.