The 80/20 approach means roughly 80% of your training time is easy and the remaining 20% is moderate to hard. This balance lets you stack up volume while staying fresh enough to nail the quality sessions that move the needle.
01What is 80/20?
The idea is simple: keep most running truly easy, then sprinkle in purposeful harder work. It's a trend over time, not perfection every week.
Translation: Most runs should feel relaxed and conversational. A small amount of well‑placed quality sharpens fitness.
02Why it Works
Builds your aerobic engine
Easy running grows capillaries, mitochondria, and fat‑oxidation—fuel for all distances.
Protects recovery
Keeping easy days truly easy lets you show up fresh for the quality sessions that matter.
More volume with less risk
Time on feet without constant stress improves durability and technique economy.
Sharpening when it counts
That 20% gives threshold/VO₂ gains and race‑pace practice without frying you.
03How to Set Intensities (No Lab Needed)
| Bucket | Feel (RPE) | Talk Test | Typical Use |
|---|---|---|---|
| Easy / Endurance | RPE 3–4/10 | Full sentences; breathing calm | Easy runs, warm‑ups/cool‑downs, most long‑run time |
| Moderate / Tempo | RPE 6–7/10 | Short phrases; controlled discomfort | Threshold blocks, steady hills, marathon‑pace |
| Hard / Interval | RPE 8–9/10 | One or two words | VO₂ intervals, 3–5K pace repeats, strides |
Use the Pace Calculator and VO₂ Max pages to cross‑check rough paces if you have a recent race.
04How to Count the 80 and the 20
- Count time, not sessions. A 60‑min easy run = 60 min easy. A 45‑min workout with 20 min of intervals = 20 min hard, 25 min easy.
- Warm‑ups/cool‑downs are easy time.
- Long runs are mostly easy; a fast finish segment counts toward the 20%.
- Big picture: Aim for 80/20 averaged over 2–4 weeks, not every single week.
| Total Weekly Run Time | Easy (~80%) | Moderate/Hard (~20%) |
|---|---|---|
| 2 hours | ~1h36 | ~24 min |
| 3 hours | ~2h24 | ~36 min |
| 4 hours | ~3h12 | ~48 min |
| 5 hours | ~4h00 | ~60 min |
05Sample Weeks (3–6 Days)
3 Days / Week
- Tue: 40 min easy
- Thu: Workout 45 min (20 min tempo inside)
- Sun: Long run 60–70 min easy
4 Days / Week
- Mon: 35–45 min easy
- Wed: Workout 50 min (e.g., 5×4 min @ tempo, 2 min easy)
- Fri: 35–40 min easy + 6×20 s strides
- Sun: Long run 70–90 min easy (last 15–20 min steady optional)
5 Days / Week
- Mon: 35–45 min easy
- Tue: Short workout (e.g., 8×1 min hard / 1 min easy)
- Thu: 40–50 min easy
- Sat: 30–40 min easy + strides
- Sun: Long run 80–100 min easy
6 Days / Week
- Mon: 35–45 min easy
- Tue: Intervals (e.g., 5×3 min @ 5–10K effort)
- Wed: 30–40 min easy
- Thu: Tempo (e.g., 2×12–15 min @ threshold)
- Fri: 30–40 min easy
- Sun: Long run 90–120 min easy
06Event Examples (5K → Marathon)
Use these blocks inside your week. Tweak volume to your level and keep the easy time around 80% overall.
| Event | Quality Ideas | Notes |
|---|---|---|
| 5K | 8–12×400 m @ 5K pace (equal jog); or 4×5 min @ 10K effort | Finish with 4–6×20 s strides |
| 10K | 3×10 min @ threshold (2–3 min easy); or 5–6×1 km @ 10K pace | Long run steady last 15–20 min every other week |
| Half | 2×5 km @ HM pace (3 min easy); or 35–45 min steady/tempo | Practice fueling on long runs |
| Marathon | 2×6–8 km @ MP (3 min easy) within a long run; or 25–40 min sustained steady | Keep most long‑run time easy |
Plan splits with the Splits tool and dial paces using the Pace Calculator.
07Common Mistakes & Fixes
- Easy runs too hard: Use the talk test. If you can’t speak comfortably, slow down.
- Too much quality: Keep the hard time near ~20%; add volume by adding easy minutes instead.
- No cutbacks: Every 3–4 weeks, reduce volume 15–30% to absorb training.
- Skipping strides: 4–8 short, relaxed 20‑second strides once or twice a week add leg pop without taxing recovery.
- Forgetting context: Heat, hills, and lack of sleep push effort up—adjust pace to keep effort honest.
08FAQs
Yes—beginners benefit most from lots of easy running. Keep “20%” very modest at first (strides, short pickups).
Helpful but not required. RPE + talk test works well. Use HR as a sanity check, not a dictator.
Great—sprinkle them in. The trick is capping them so you can do more total running and stay healthy.
Treat it as your weekly quality (either a hard effort or a controlled tempo) and keep the rest easy.
Note: This guide is general information only and not medical advice. If you have health concerns or persistent pain, seek professional guidance.
Last updated: August 28, 2025