How slow should easy runs be?

Slow enough to hold a conversation throughout. For most recreational runners that is a minute or more per kilometre slower than 10 km race pace.

Is zone 2 the same as easy running?

Broadly yes for most models, though zone definitions vary between systems. The talk test is a more robust guide than a zone number from an unvalidated maximum heart rate estimate.

Will running slower make me slower?

No. Speed comes from the hard sessions; easy volume is what lets you do them well and repeatedly.

What is 80/20 running?

A shorthand for spending roughly 80% of training volume at low intensity and 20% at high intensity, based on observed training distributions in endurance athletes.

Running6 min readUpdated 16 September 2026

Why your easy runs might not be easy enough

The most common pattern in recreational running is a week of moderately hard efforts: not easy enough to recover from, not hard enough to drive adaptation. Everything ends up in the middle, and progress flattens.

What the research supports

What the research says

Successful endurance athletes do the large majority of their training at low intensity.

Analyses of training-intensity distribution across endurance sports repeatedly find roughly 75–85% of training volume performed below the first ventilatory or lactate threshold, with a small share at high intensity.

Stöggl & Sperlich · Frontiers in Physiology · 2015 · Peer-reviewed research

What the research says

Increasing volume too quickly, rather than too slowly, is what shows up in injury data.

A prospective study of novice runners found sharp week-to-week increases in running distance associated with a higher rate of distance-related injuries — a risk that easy running makes more manageable because it is easier to absorb.

Nielsen et al. · Journal of Orthopaedic & Sports Physical Therapy · 2014 · Peer-reviewed research

Four ways to find your easy pace

If two methods disagree, take the slower one. The cost of running an easy run too slowly is close to zero; the cost of running it too fast is a compromised quality session later in the week.

Two ways a week can go wrong

Everything moderate

Suits — Feels productive and consistent

Costs — Hard sessions are never sharp; fatigue accumulates quietly

Easy genuinely easy, hard genuinely hard

Suits — Better quality sessions, better recovery, clearer progression

Costs — Easy days can feel unsatisfying at first

Why it feels wrong at first

Slowing down exposes the assumption that every run should be an achievement. It also takes a few weeks: aerobic adaptations accumulate, and the same effort gradually produces a quicker pace. If you find that your easy pace is barely faster than walking, that is a sign of the fitness you are building, not a verdict on you.

How CALIBR handles it

CALIBR prescribes easy runs as an effort and a pace band derived from your own recent running, not from a generic table, and the guided run tells you when you have drifted above it. Your pace calculator is available in the tools section if you want to check the numbers yourself.

Key takeaways

Easy means conversational — full sentences, not gasped phrases.
Roughly 60–90 s/km slower than 10 km pace is a reasonable starting estimate.
Around 80% of weekly running volume should sit there.
When two pacing methods disagree, take the slower one.
Easy running is what protects the quality of your hard sessions and your lifting.

Common questions

References

[1]The training intensity distribution among well-trained and elite endurance athletesStöggl & Sperlich · Frontiers in Physiology · 2015 · Peer-reviewed research
[2]Excessive progression in weekly running distance and risk of running-related injuriesNielsen et al. · Journal of Orthopaedic & Sports Physical Therapy · 2014 · Peer-reviewed research
[3]Concurrent training: a meta-analysis examining interference of aerobic and resistance exerciseWilson et al. · J Strength Cond Res · 2012 · Systematic review
[4]ACSM's guidelines for exercise testing and prescriptionAmerican College of Sports Medicine · 2025 · Professional guidance
[5]The training—injury prevention paradox: should athletes be training smarter and harder?Gabbett · Br J Sports Med · 2016 · Peer-reviewed research