Mighty Nimble
Mighty Nimble
Download App

Intermediate Half Marathon Run

A 25-minute run session to build half marathon endurance with a controlled tempo block.

Warm-Up

Gradually raise heart rate and loosen up before the tempo effort.

Easy Run
Easy Run10 min

Main Set

Sustained tempo effort to build half marathon-specific stamina.

Tempo Run
Tempo Run10 min

Cool-Down

Bring your effort down gradually and finish feeling recovered.

Easy Run
Easy Run5 min
Tempo Runs Build Your Lactate Ceiling

Tempo Runs Build Your Lactate Ceiling

The tempo block targets your lactate threshold — the pace where lactate accumulates faster than your body clears it. Sustained effort here trains your aerobic system to process lactate more efficiently, directly raising the pace you can hold for 13.1 miles without fading.

The Half Marathon's Cruel Middle Miles

The Half Marathon's Cruel Middle Miles

The half marathon punishes runners who go out too hard — glycogen depletion and neuromuscular fatigue compound after mile 8. Your easy run segments train fat oxidation and active recovery between efforts, conditioning your body to sustain form and economy when the race gets uncomfortable.

Structure Your Effort Around Heart Rate Zones

Structure Your Effort Around Heart Rate Zones

This session pairs Zone 2 easy running with Zone 3-4 tempo work, a classic polarized approach that builds aerobic base without accumulating excessive fatigue. To personalize it, anchor your tempo pace to your current 10K race pace minus 15-20 seconds per mile — not perceived effort alone.

Intermediate Half Marathon Run | Mighty Nimble | Mighty Nimble