A real step up: after the five-minute warmup walk you run three minutes, walk 90 seconds, run five minutes, walk two and a half minutes, then repeat the run-walk-run before the five-minute cooldown. The session totals 31:30 — your longest yet, with 16 minutes of running inside it.
Week 4 asks for three outings of this same timer, rest days between. Five minutes is a leap from three, so treat each long run as an exercise in restraint: settle in within the first minute and stay there. As the distances grow familiar over the week, spend the later runs on form — eyes up, shoulders loose, quick light steps.
A longer continuous run lands in week three: 90 seconds, then three minutes, twice through with walking recoveries. Three sessions this week with rest days between — trust the build-up.
Past the halfway point: three five-minute runs with three-minute walking recoveries. Warm up properly to keep injuries away and prepare for the bigger efforts ahead.