How to Train for a Marathon on the Treadmill (Winter Survival Guide)

Winter doesn’t have to derail your build. Here’s how to use the treadmill effectively without losing road-readiness.

How to structure your weeks

• Keep the same weekly rhythm: 1 long run, 1 quality workout, 2–3 easy runs, strides 1–2x/week.
• Cap most treadmill long runs at 90–120 minutes; split very long days into AM/PM (e.g., 10 + 6).
• Rotate workouts: tempos, cruise intervals, short hills (incline reps), and progression runs.

Pacing and effort on the treadmill

• Use effort/HR and feel; many treadmills read a bit fast/slow.
• Slight incline (0.5–1.0%) mimics outdoors; no need to go steeper unless doing hill reps.
• For tempo/threshold, use steady segments (10–20 minutes) or cruise intervals (6–10 minutes) with short recoveries.

Long runs inside (without going crazy)

• Break them up: e.g., 60–75 minutes AM, 45–60 minutes PM.
• Progression finish: start easy, finish last 15–20 minutes at moderate effort to keep interest up.
• Entertainment stack: playlists, podcasts, or a show; change pace every 10–15 minutes to avoid monotony.

Hill and strength work

• Hill reps: 6–10 x 60–90 seconds at 4–6% with full recoveries easy/flat.
• Light strength 2–3x/week: single-leg work, core, hip stability—especially important when outdoor variability is low.

Transitioning back outdoors

• Add 1–2 outdoor runs per week as conditions allow; include strides to reintroduce turnover.
• First outdoor long run: keep it easy and shorter than your peak indoor long run.
• Watch for calf/hamstring tightness when you reintroduce varied terrain—warm up thoroughly and add mobility.

Fueling and hydration indoors

• You still sweat: ventilate the room, use a fan, and drink 12–20 oz/hour with some electrolytes.
• Practice race fueling at workout intensities (30–60 g carbs/hr for most).

When to choose outside anyway

• Dress for it if footing is safe: traction devices, layered technical gear, windproof outer.
• If ice or extreme wind-chill make it unsafe, stay indoors—consistency beats hero runs.

Using The Next Race

• Log treadmill runs with incline and effort notes.
• Plan split long runs and track both parts.
• Schedule hill reps and strides; note fueling trials for race rehearsal.