How it works
blended pace = (run secs + walk secs) ÷ (run distance + walk distance)
A cycle is scored by what it covers, not how it feels. Two minutes of running at 9:00 per mile advances you 2/9 of a mile; thirty seconds of walking at 18:00 per mile adds another 1/36 — a quarter mile total in 2:30 of clock time, which blends to 10:00 per mile. The formula generalizes exactly that: add the run and walk seconds, divide by the summed distances, and any ratio you try resolves to one honest average. The projected finish multiplies the blend by your race distance, on the assumption that you repeat the cycle from the start line to the end rather than abandoning walks whenever mile three feels good.
Sources
- Galloway Run-Walk-Run method Jeff Galloway, “Galloway’s Book on Running” and the Run-Walk-Run method — strategic walk breaks reduce fatigue and injury while maintaining overall pace.
- Blended pace is a weighted average Average pace over mixed efforts is total time divided by total distance — the standard time-weighted mean of the run and walk segments.
- Walk breaks and endurance Interspersing walk breaks early conserves glycogen and muscle, which is why many runners finish faster overall with run-walk than running continuously to exhaustion.
FAQ
What run-walk ratio should a beginner start with?
Short and even — run 1:00, walk 1:00, at a conversational running pace. As fitness builds, stretch the run side toward two to five minutes while keeping walks near 30 seconds. The preset buttons (30-, 60-, and 120-second runs; 15-to-60-second walks) bracket most combinations worth testing.
How much time do the walk breaks actually cost?
Less than intuition claims. With the defaults — 2:00 running at 9:00 per mile, 0:30 walking at 18:00 — the walks slow the average by exactly one minute per mile, to 10:00. Across a half marathon that is about 13 minutes on paper, and a stronger final third typically claws a chunk of it back.
What walking pace should I enter?
Time an actual brisk training walk instead of guessing — purposeful walkers mostly land between a 15:00 and 20:00 mile, and the default assumes 18:00. Enter a stroll you will not really hold and the projection turns pessimistic; this tool is only as honest as the two paces you feed it.
Does run-walk hold up over a full marathon?
It is arguably at its best there. Set the distance to 26.2 and compare interval schemes: the payoff grows with distance, because early walks protect legs and glycogen for the late miles where continuous runners fade hardest. Galloway-trained runners negative-split marathons this way routinely.
Do I take walk breaks from the very first mile?
Yes — that is the heart of the method, and it is what the projection assumes. The early breaks, taken while you still feel fresh, are the ones doing the protective work. Improvising walks only after fatigue arrives turns a strategy back into damage control.
Why does my watch average differ from the blend shown here?
The calculator assumes clean transitions and constant paces within each mode; a real session adds a second or two of deceleration at every switch, GPS wobble, and pace drift late in the run. Expect a well-executed effort to land within a few seconds per mile of the projection, not on top of it.
The blended pace and finish projection follow mathematically from the four numbers you enter — they say nothing about whether those paces suit your body on a given day. Build interval fitness gradually and let effort override the schedule when something hurts. Training reference only, not medical or coaching advice.