Should You Start Marathon Training Now? The 18-Week Indianapolis Monumental Window

The Monumental is November 7. If you're sitting here wondering whether now is the right time to start training, the answer is yes. You're almost exactly 18 weeks out.

Most runners I work with make one of two mistakes. They start too late and have to rush the build, which usually means getting hurt or falling apart in the second half of the race. Or they start way too early, peak in September, and show up in November with flat legs and no motivation left. Starting now gives you time to build real aerobic fitness, get some quality work in, run a tune-up race in the fall, and still taper properly before race day.

Here's how I structure an 18-week Monumental build.

Weeks 1-6: Base Phase

Not glamorous. You're running easy, adding volume gradually, and building the aerobic foundation that everything else sits on top of. If you raced in the spring, this is also your recovery window. I usually start athletes around 60-80% of their peak spring mileage and don't add more than 10% per week. No heroics. Just consistent, honest miles.

If you're coming in fresh with no spring race behind you, start even more conservatively. Building from 15-20 miles per week toward 40+ by week six leaves plenty of room to grow.

Weeks 7-12: Development Phase

This is where training gets fun. Aerobic tempo runs come in. Marathon-pace work starts. Long runs push past 16 miles by the end of this stretch. If you're chasing a BQ, this is where we lock in your goal pace and start training your body to hold it. If this is your first marathon, this is where you learn what your body can actually handle, which is exactly why having someone watching your training matters.

Your long run is the most important workout in this phase. It should feel controlled. If you're finishing them wrecked and needing two full days to bounce back, you're running them too fast.

Weeks 13-16: Race Simulation

This is the sharpening block. Long runs start to include race-pace miles at the end. A lot of athletes do a half marathon tune-up in September or October to test their fitness and get some real race experience before November. We're also keeping a close eye on training load here because this is when overuse injuries sneak in if recovery isn't a priority.

Weeks 17-18: Taper

Your fitness is set by week 16. The taper is part of the training, not a break from it. Your muscles are repairing, glycogen stores are topping off, your nervous system is resetting. You're going to feel weird and restless. That's completely normal. Trust what you've built.

If you haven't locked in a plan for November yet, now is the time. The structure you put in place over the next 18 weeks is what determines how race day goes. Reach out if you want to talk through it. That's exactly what the free 15-minute consultation is for.

Coach Justin