What is running pace and how is it calculated?
Pace is the time it takes to cover one unit of distance — expressed as minutes per kilometre (min/km) or minutes per mile (min/mile). It is the inverse of speed. Pace = Time ÷ Distance. For example, completing a 10K in 55 minutes = 55 ÷ 10 = 5:30 min/km. To convert: Speed (km/h) = 60 ÷ Pace (min/km). At 5:30/km, speed = 60 ÷ 5.5 = 10.9 km/h.
What are average running paces for 5K, 10K, half marathon, and marathon?
5K — beginner: 7–8 min/km (35–40 min); intermediate: 5–6 min/km (25–30 min); advanced: 4 min/km (20 min); elite: 2:50/km (14 min). 10K — beginner: 7 min/km (70 min); intermediate: 5:30/km (55 min); advanced: 4:10/km (41 min). Half marathon average finish: ~2:15. Marathon average finish: ~4:30 (recreational runners).
How do I calculate my marathon or half marathon finish time from a training pace?
A rough projection: 5K time × 2.09 = 10K; 5K × 4.667 = half marathon; 5K × 9.927 = marathon. However, pace typically slows over longer distances due to fatigue (5–15% for a half marathon, 15–30% for a full marathon compared to 5K pace). This calculator applies the Riegel formula to project realistic race finish times from your current performance.
What is the difference between aerobic and anaerobic running pace?
Aerobic pace (comfortable, conversational) is sustainable for long distances — the body uses predominantly fat and oxygen. Lactate threshold pace is the fastest pace at which lactic acid can be cleared (typically 10K–half marathon race pace). Anaerobic pace (above threshold) produces lactic acid faster than it clears, causing burning muscles and rapid fatigue — sustainable for only 1–10 minutes depending on intensity.
How should I pace myself in a race to avoid hitting the wall?
"Even pacing" or slight "negative splits" (running the second half a little faster than the first) consistently produces the best race times. Going out too fast — even 5–10 seconds per km above target pace in the first half — depletes glycogen stores prematurely and causes dramatic slowdown in the final kilometres (the dreaded "wall"). In a half marathon, aim to run the first 5 km 10–15 seconds per km slower than your target race pace.