Three variables govern every run: Pace, Distance, and Time. Know any two and you can calculate the third:
Pace and speed are inversely related: Speed (km/h) = 60 ÷ Pace (min/km). A pace of 5:00 min/km equals 12 km/h. A pace of 6:00 min/km equals 10 km/h.
Converting between min/km and min/mile: Multiply pace in min/km by 1.60934, or divide pace in min/mile by 1.60934. A 6:00 min/km pace equals 9:39 min/mile.
Use this reference table to find the exact pace you need to hit your goal finish time:
| Goal Time | Race | Required Pace (min/km) | Required Pace (min/mile) |
|---|---|---|---|
| 25:00 | 5K | 5:00 | 8:03 |
| 30:00 | 5K | 6:00 | 9:39 |
| 45:00 | 10K | 4:30 | 7:14 |
| 1:00:00 | 10K | 6:00 | 9:39 |
| 1:45:00 | Half Marathon | 4:59 | 8:01 |
| 2:00:00 | Half Marathon | 5:41 | 9:09 |
| 3:30:00 | Marathon | 4:58 | 7:59 |
| 4:00:00 | Marathon | 5:41 | 9:09 |
| 4:30:00 | Marathon | 6:24 | 10:18 |
| 5:00:00 | Marathon | 7:06 | 11:26 |
Effective training requires running at different intensities. Here are the five standard training pace zones, defined relative to your 5K race pace:
| Zone | Name | Intensity | Pace vs 5K Race Pace | Purpose |
|---|---|---|---|---|
| Zone 1 | Easy / Recovery | 60–70% max HR | +2:00 to +3:00 min/km | Recovery, base building |
| Zone 2 | Aerobic / Long Run | 70–80% max HR | +1:00 to +2:00 min/km | Endurance, fat burning |
| Zone 3 | Tempo | 80–87% max HR | +0:15 to +0:45 min/km | Lactate threshold |
| Zone 4 | Threshold / Race Pace | 87–92% max HR | ~5K race pace | Race simulation |
| Zone 5 | VO2 Max / Interval | 92–100% max HR | Faster than 5K pace | Speed, VO2 max |
The 80/20 rule: Research by exercise scientist Dr. Stephen Seiler shows that elite and recreational runners who spend ~80% of their training in Zones 1–2 and only ~20% in Zones 3–5 improve faster than those who train hard every day.
"Good" pace is highly personal and depends on age, fitness level, and goals. Here are typical reference points:
| Level | 5K Time | Average Pace (min/km) | Average Pace (min/mile) |
|---|---|---|---|
| Beginner (first 5K) | 35–45 min | 7:00–9:00 | 11:15–14:30 |
| Recreational runner | 25–35 min | 5:00–7:00 | 8:03–11:15 |
| Club runner | 20–25 min | 4:00–5:00 | 6:26–8:03 |
| Sub-elite | 15–20 min | 3:00–4:00 | 4:50–6:26 |
| Elite / Olympic | Under 14 min | Under 2:50 | Under 4:33 |
For beginners, aim for a pace where you can hold a conversation. This "conversational pace" keeps you in Zone 1–2, building aerobic base without risking injury or burnout. Most beginners improve rapidly — a 9:00 min/km runner can often reach 7:00 min/km within 3 months of consistent training.
A negative split means running the second half of a race faster than the first. It is the most consistent strategy used by world record holders across distances from 800m to the marathon.
Why it works: Starting too fast (positive splitting) depletes glycogen and causes lactic acid buildup, leading to a dramatic slowdown in the final miles. A conservative start preserves glycogen, allowing you to accelerate when others fade.
Example for a 4:00 marathon (5:41 min/km average):
Aim to run the first half 1–2% slower than goal pace. For a 4:00 marathon, start at 5:45–5:50 min/km rather than exactly 5:41.
Speed improvement comes from a combination of physiological adaptations, each requiring different training stimuli:
Most runners improve fastest by running more miles at easy pace before adding intensity. If you are under 30–40 miles per week, adding volume will improve pace more than adding speed workouts.
"Appropriate pacing strategy is one of the most critical determinants of distance running performance. Research consistently demonstrates that starting at an even pace or slightly slower and accelerating in the second half produces superior outcomes compared to positive splits."
A comfortable pace for beginners is typically 7:00–9:00 minutes per kilometer (11:15–14:30 per mile). Focus on running at a conversational pace — if you can't speak in full sentences, slow down. Speed will come naturally with consistency.
The most effective methods are: (1) run more miles per week at easy pace, (2) add one weekly tempo run at about 85% max heart rate, (3) include interval training (e.g., 5×1000m at 5K pace), and (4) add lower-body strength training twice per week. Most improvement comes from consistent easy mileage.
A sub-4-hour marathon requires an average pace of approximately 5:41 per km (9:09 per mile) over the full 42.195 km. Given typical race-day fatigue, train at 5:45–5:50 per km to build margin.
Multiply your min/km pace by 1.60934. For example, 5:00 min/km × 1.60934 = 8:03 min/mile. To go the other way, divide min/mile by 1.60934: 9:00 min/mile ÷ 1.60934 = 5:35 min/km.
Pace is the time taken to cover a unit distance (e.g., 5:30 per km). Speed is the distance covered per unit time (e.g., 10.9 km/h). They are inversely related: Speed (km/h) = 60 ÷ Pace (min/km). A 6:00 min/km pace equals exactly 10 km/h.
Your long run should be 60–90 seconds per km slower than your goal marathon pace, or about 65–70% of maximum heart rate. This keeps you in the aerobic zone for building endurance without accumulating fatigue. For a 5:00 min/km marathon runner, long runs at 6:00–6:30 min/km are appropriate.
A negative split means running the second half of a race faster than the first. It is the strategy used by most world record-setting performances. Starting conservatively preserves glycogen and avoids early lactic acid buildup, allowing you to accelerate in the second half when most competitors are fading.
Consumer GPS watches are typically accurate to within 1–2% for distance, which means paces can be off by 5–10 seconds per km. Tunnels, tall buildings, and dense tree cover increase error. For track workouts, use the measured distance rather than GPS for the most accurate pace data.