The Truth About Long Runs

The weekly long run evolved from Arthur Lydiard’s coaching philosophy to maintain aerobic development during competition phases. Long runs build endurance capacity, but their purpose and optimal frequency vary by event and training phase. Most runners misunderstand when and why to include them.

Historical Context

The modern weekly long run originated with Arthur Lydiard, the godfather of modern endurance training, in the 1950s-60s. Before that, athletes did long walks in the early 1900s, but running-based long runs weren’t standard until the mid-20th century.

Lydiard’s insight was elegant: a single weekly longer run could serve two distinct purposes depending on training phase.

Purpose of the Long Run

During Base Phase: Development

The long run builds aerobic endurance capacity—the foundation for sustaining race pace. It:
– Increases mitochondrial density
– Develops capillarization (oxygen delivery)
– Trains the aerobic system to work efficiently
– Builds mental toughness through extended effort
– Teaches pacing and body awareness

During Competition/Sharpening Phase: Maintenance

Once aerobic development is maximized, a single weekly long run maintains that capacity while the athlete emphasizes speed work, intervals, and race-specific training. Without it, endurance adaptations degrade despite high-intensity work.

This was Lydiard’s critical discovery: intensity alone doesn’t preserve aerobic development—you need at least one longer, aerobic stimulus weekly.

How Long Should Long Runs Be?

This varies significantly by event and athlete level:

Marathon Training

Minimum: 16-20 miles
Typical range: 18-24 miles
Frequency: Once weekly (sometimes twice in very high-volume programs)
Purpose: Build the specific endurance to sustain marathon pace for the full distance

5K/10K Training

Range: 10-16 miles
Frequency: Once weekly
Note: Exact length matters less than ensuring aerobic stimulus; 90+ minutes of continuous running achieves physiological adaptations

XC/High School Runners (5K-ish distance)

Range: 8-14 miles depending on athlete level
Frequency: Once weekly
Progression: Build gradually through season; don’t peak too early
Note: High school runners shouldn’t do ultra-long runs early in season

1500m/Mile

Range: 8-12 miles
Less critical than for longer distances but still important for aerobic base
Can sometimes substitute harder efforts if volume is limited

Common Myths About Long Runs

Myth 1: “You Need to Match Race Distance”

False. A 5K runner doesn’t need to run 5 miles at race pace. The long run is about aerobic development and time on feet, not race-specific pace.

Myth 2: “Long Runs Must Be Slow”

Partially true. Long runs should be easy enough for conversation, but not necessarily “shuffle slowly.” For elite athletes, “easy” might be 7:00/mile; for others, 9:00/mile. The key is sustainable aerobic pace.

Myth 3: “Longer is Always Better”

False. Excessive long run distance causes:
– Unnecessary glycogen depletion
– Extended recovery needs
– Injury risk from repetitive load
– Compromise of other essential workouts

Lydiard’s weekly long run was the minimum effective dose, not a maximum.

Myth 4: “Everyone Needs One”

False. Lactate Threshold Training and speed work matter more for middle-distance runners (800m-1500m). Long runs matter less for 400m specialists. The longer the race, the more critical the long run.

Integration Into Training Phases

Base Phase

Frequency: Once weekly (or occasionally twice for elite marathoners)
Build gradually: Start at sustainable length, add 1-2 miles per week
Pace: Conversational, steady aerobic effort
Support: Build from Zone 2 Training for High School Runners base

Build Phase

Frequency: Once weekly, possibly one secondary longer run
Length: At or approaching peak distance
Pace: Slightly faster than base phase but still aerobic
Timing: Usually place before intense interval sessions in the week

Competition/Taper Phase

Frequency: Once weekly
Length: Reduced (70-80% of peak) to manage fatigue
Pace: Can increase slightly; still primarily aerobic
Purpose: Maintenance of aerobic capacity without compromising recovery for racing

Peak/Championship Week

Frequency: Often omitted entirely
Rationale: Full recovery prioritized over training stimulus

Long Run Pacing

The mistake: Running long runs too fast. Runners confuse “building endurance” with “running at threshold.”

The truth: Adaptations happen at easy effort levels. Running the long run in zone 3 or 4:
– Creates excess fatigue
– Requires more recovery
– Limits other training quality
– Misses the point (aerobic development happens best at conversational effort)

Sweet spot: Effort where you could hold a conversation but are slightly breathing hard. For different athletes:
– Elite marathoners: 6:30-7:30/mile
– Competitive 5K: 7:30-8:30/mile
– Recreational 5K: 8:30-10:00/mile
– High school varsity: varies widely, but typically 6:30-8:00/mile

Length Progressions

Safe Build-Up (Increasing Mileage)

If building for first time or returning from break:
– Start at sustainable length (whatever you’ve done recently)
– Add 1-2 miles every 2-3 weeks
– Take a down week (20% reduction) every 3-4 weeks
– Listen to body; don’t force progression if niggles appear

Example progression (marathon training):
– Week 1-2: 10 miles
– Week 3: 11 miles
– Week 4: 10 miles (down week)
– Week 5: 12 miles
– Continue until reaching 18-20 mile peak

High School XC Progressions

Early season: 6-8 miles
Mid-season: 8-12 miles
Peak season: 10-14 miles (depending on athlete level)
Taper: 8-10 miles (reduced)

Don’t rush; athletes develop gradually over 4-year high school careers.

Long Run Nutrition and Pacing Strategy

For long runs exceeding 90 minutes:

Fueling: Consume 30-60g carbs/hour (gels, sports drink, real food)
Hydration: Drink to thirst, roughly 500-750ml/hour depending on conditions
Pacing strategy: Negative split if possible—go out conservatively, finish strong
Mental game: Break the run into smaller segments (by distance or landmarks)

Integration with Other Training

Weekly Structure Example (5K/XC)

Monday: Easy run (4-6 miles) + strength
Tuesday: Intervals or tempo (hard workout)
Wednesday: Easy run (4-6 miles)
Thursday: Easy run + strides (4-5 miles)
Friday: Easy or rest
Saturday: LONG RUN (10-14 miles, conversational pace)
Sunday: Easy run or rest (4-5 miles)

The long run sits when fatigue is lowest (after rest day).

When Long Runs Conflict with Other Training

If you’re doing multiple workouts daily or have high volume elsewhere:
– Consider if long run distance can be reduced (time-based instead of distance-based)
– Can a secondary long run substitute cross-training?
– Is total volume sustainable with recovery capacity?

The Bottom Line

Purpose shifts – Base phase development vs. competition phase maintenance
Once weekly minimum – For any distance from 1500m up; more for marathoners
Aerobic pace – Conversational, not hard; adaptations happen in zone 2
Gradual progression – Don’t force distance; build sustainably over weeks
Length varies – Depends on event distance and athlete level
Integration matters – Place strategically in weekly structure
Don’t obsess – It’s important but not magical; consistency matters more than perfection

The Lydiard Principle

Arthur Lydiard’s insight remains valid: a consistent, weekly aerobic stimulus (the long run) maintains endurance capacity during high-intensity phases. This single element, combined with Building the Championship XC Season intensity and quality work, is foundational for any distance runner.

Related topics: Mileage Manifesto, Building the Championship XC Season, Zone 2 Training for High School Runners, Safe Summer Base Mileage