Long Run

The cornerstone weekly run — a sustained easy-pace effort that builds endurance, mental toughness, and fat-burning efficiency.

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Understanding Long Run

The long run is the single most important weekly workout for any runner training for a half marathon or longer. It's a sustained easy-pace effort — typically your slowest running of the week — designed to build endurance, teach your body to burn fat, strengthen connective tissues, and develop the mental resilience to keep going when you're tired.

Long runs progressively increase in distance throughout a training plan, usually peaking at 16–22 miles for a marathon or 10–13 miles for a half. The pace should be conversational — 1–2 minutes per mile slower than goal race pace. Many runners go out too fast on long runs and finish wrecked; the purpose isn't speed, it's time on your feet.

Beyond the physiological benefits, long runs simulate the race experience. They're where you practice fueling, test gear, learn your body's response to fatigue, and build confidence. A runner who has done a 20-mile training run knows they can handle the distance; that mental bank is worth as much as the physical fitness.

Key Facts: Long Run

Key facts and insights about long run that every endurance athlete should know.

Typically the longest run of the week, d

Typically the longest run of the week, done at easy/conversational pace

Marathon plans peak at 18–22 miles; half

Marathon plans peak at 18–22 miles; half marathon plans peak at 10–13 miles

Pace should be 1–2 min/mile slower than

Pace should be 1–2 min/mile slower than goal race pace

Builds mitochondrial density, capillary

Builds mitochondrial density, capillary networks, and fat oxidation capacity

Pro Tips: Long Run

Run your long runs SLOW — if you finish feeling destroyed, you went too fast

Practice your exact race-day nutrition: same gels, same timing, same fluids

Don't increase your long run distance by more than 2 miles (or 10–15%) from the previous week

Run your long run on terrain similar to your goal race when possible

Frequently Asked Questions About Long Run

Slow enough to hold a full conversation without gasping. For most runners, that's 1:30–2:00 per mile slower than 5K pace. If your marathon goal pace is 9:00/mi, your long runs should be around 10:00–11:00/mi. It feels embarrassingly slow — that's correct.

No. Most plans peak at 20–22 miles, not 26.2. The physiological benefits plateau after ~3 hours of running, and the injury risk of a full marathon-distance training run outweighs the benefit. The taper, race-day adrenaline, and fueling carry you the final miles.

Walk breaks are perfectly fine and even strategic. The Galloway run/walk method (e.g., run 4 minutes, walk 1 minute) is used by thousands of successful marathoners. Walking doesn't mean you failed — it means you're managing effort intelligently.