Marathon Running: Long Run Benefits

Summary

In marathon training, the long run isn’t optional, it’s the single most important session in your plan. These extended efforts train your body to stay efficient over distance, improve fuel usage and build the mental strength needed to finish strong. Whether you’re aiming for a sub-4:00 or just crossing the line, this post explains why long runs matter more than anything else in marathon prep and how to make them count.

Why Long Runs Are Non-Negotiable for the Marathon

The marathon is a test of endurance, efficiency and pacing discipline. Success doesn’t come from speed alone, it comes from your ability to stay smooth and composed when the race moves beyond two hours. That ability is built during long runs.

Long runs:

• Train your body to use fuel more efficiently

• Build structural durability in muscles, tendons, and joints

• Improve mental stamina when glycogen is low

• Help you rehearse race-day pacing, fuelling and mindset

Skipping long runs or doing them without intention, leaves massive holes in your marathon preparation.

Understanding the Marathon’s Physiological Demands

The marathon is nearly 100% aerobic, but that doesn’t make it easy. It places extended stress on every system in the body:

• Muscular endurance: To keep form at 35K

• Fuel management: To avoid the wall

• Mental focus: To stay composed over 2–5 hours

• Hydration balance: To maintain performance in later stages

Long runs simulate these stresses in a controlled, progressive way. That’s why they are the cornerstone of any marathon plan, from beginner to elite.

How Long Should a Marathon Long Run Be?

There’s no magic distance, it depends on your experience, weekly volume and goal.

That said, marathon long runs generally fall between:

• Novice runners: 2:00–2:30 hr (up to 28K or ~17 miles)

• Intermediate runners: 2:30–3:00 hr (up to 32K or ~20 miles)

• Advanced runners: 2:45–3:15 hr (32–36K or ~20–22 miles)

The key is time on feet, not distance. Most runners hit diminishing returns past 3 hours unless preparing for ultra-style races. It’s better to arrive at race day fresh than to overtrain in pursuit of one massive run.

Top 5 Benefits of Long Runs for Marathon Training

1. Builds Fat-Burning Efficiency

The longer you run, the more your body learns to rely on fat as a fuel source, preserving glycogen for the later miles. This delays the dreaded wall at 32–35K.

2. Increases Muscular Resilience

Time on feet strengthens key running muscles (glutes, hamstrings, calves) and reinforces tendon strength, reducing injury risk and maintaining form deep into the race.

3. Trains Fueling and Hydration Strategies

You can’t wing marathon nutrition. Long runs are the perfect place to test gel timing, fluid intake and gut tolerance so there are no surprises on race day.

4. Builds Mental Stamina

There’s no shortcut to the mental grind of late-race fatigue. Long runs teach you how to stay calm, focused and efficient when you’d rather stop.

5. Rehearses Race Pace Execution

Practicing segments at or just below marathon pace helps lock in rhythm, reinforce pacing control and improve confidence heading into race day.

How to Run Your Long Runs

Run in Zone 2

Most long runs should stay in Zone 2 (73–80% of max heart rate). An easy, steady effort. You should be able to hold a relaxed conversation.

Build Gradually

Start your plan with long runs around 60 minutes and build up by 10–15 minutes or 1–2 kilometres each week. Include step-back weeks every 3–4 weeks to allow recovery.

Include Fuel and Fluids

Start fuelling early, typically around 45 minutes in and continue every 30–40 minutes. Hydrate every 15–20 minutes, especially in warmer conditions.

Examples of fueling during long runs:

• 2–3 energy gels

• Electrolyte drink or water

• A small snack (banana, energy chew)

Avoid Late-Week Intensity

Don’t stack your long run right after a hard tempo or interval session. Give yourself recovery days to maximise quality and reduce injury risk.

Types of Long Runs in Marathon Training

1. Standard Long Run (Zone 2)

The core of your plan, steady effort at an easy pace. Focus on distance, rhythm, and form.

2. Progression Long Run

Last 20–30 minutes slightly faster, building toward marathon pace or strong aerobic finish. Great for building late-race strength.

3. Race-Pace Long Run

Include 8–16K at goal marathon pace in the middle or final third of the run. This teaches control, fuelling under stress and pacing confidence.

4. Back-to-Back Long Run Blocks

Advanced method: medium-long run Saturday, longer run Sunday. Teaches cumulative fatigue handling. Use sparingly.

Alternate between formats every 1–2 weeks to keep adaptations moving without overwhelming the body.

When Should Your Longest Run Be?

Your longest run should happen 2–3 weeks before race day, depending on your plan and how your body responds to volume.

A typical progression:

• Week 4 before race: 28–30K

• Week 3: Peak long run — 32–36K or 3:00 max

• Week 2: Drop to 20–22K

• Week 1: 8–12K shakeout before taper

Don’t force a 20-miler if you’re not ready, being undertrained is better than being overcooked.

FAQ: Long Run Benefits

What is the minimum long run I need for a marathon?

Aim for at least 2–3 runs of 28–32K before race day. If you’re newer, focus on time (2.5–3 hours) rather than distance.

Should I run the full marathon distance in training?

No. It’s not necessary and often harmful. Save that effort for race day. Peak long runs should cap around 3 hours or 32–36K.

How fast should I run my marathon long run?

Keep most long runs in Zone 2. Only occasionally include segments at marathon pace to rehearse intensity.

What if I feel wiped out after every long run?

You may be going too hard, building up too fast or underfueling. Long runs should feel challenging, not destructive.

How many long runs should I do during marathon training?

Typically 8–10 long runs over a 12–16 week plan. Include step-back weeks for recovery and avoid doing max distance more than once or twice.

Final Thoughts

Marathon success isn’t built overnight, it’s built through smart, consistent long runs that teach your body how to go farther with control.

These sessions aren’t about speed. They’re about strength, stamina and staying efficient when it counts. If there’s one session you never skip in marathon training, make it the long run.

Is your long run building a marathon engine or just ticking off the miles?

Always consult with a medical professional or certified coach before beginning any new training program. The information provided is for educational purposes only and is not a substitute for personalized advice.