Chester Treadmill Test — How To Pass UK Firefighter Selection

What Is The Chester Treadmill Test?

The Chester step test (in its treadmill variant) requires you to walk at a fixed speed of 6.2km/h on a treadmill for 12 minutes, with the gradient increasing every 2 minutes from 0% to 15%. You must complete the full 12 minutes without holding the handrails.

Your heart rate is monitored throughout. The result estimates your VO2 max — the volume of oxygen your body can use per kilogram of bodyweight per minute. UK fire services require a minimum of 42ml/kg/min.

The Most Common Mistake

Most candidates train by running. But the Chester treadmill test is not running — it's incline walking at a fixed speed. The muscle patterns, the cardiovascular demands, and the technique are completely different. You must train specifically for it.

The Gradient Stages

The test progresses through six stages of 2 minutes each, with incline increasing by 3% per stage:

0:00–2:00 — 0%: Easy. Settle in. Find your rhythm.
2:00–4:00 — 3%: Slight incline. Still comfortable. Breathing picks up slightly.
4:00–6:00 — 6%: Working. Noticeably harder than flat walking. Posture matters.
6:00–8:00 — 9%: Hard. Lean slightly forward. Shorten your stride.
8:00–10:00 — 12%: Very hard. Do not grab the rails. Breathe steadily.
10:00–12:00 — 15%: Maximum. Every step counts. You're nearly there.

The Four Rules

Do not hold the rails — this invalidates the test at most UK fire services.
Speed stays at 6.2km/h — do not adjust it at any point.
Lean slightly forward at steep inclines — don't lean back or fight the treadmill.
Shorten your stride above 9% — overstriding wastes energy and throws off balance.

How To Train For The Chester Test

Incline Walking Sessions

The most direct preparation: treadmill walks at 6.2km/h with rising incline. Start with 15 minutes and build to 20+ minutes. Increase the starting and finishing incline week by week. This builds the specific muscle and cardiovascular endurance the test demands.

Aerobic Running

Zone 2 running 2–3 times per week builds the aerobic base that makes the Chester test manageable. Interval training raises your aerobic ceiling so 42ml/kg/min feels comfortable rather than maximal.

Do Not Hold The Rails In Training

Never touch the rails in training. Build the balance and strength to walk at steep inclines without support. If you practice holding the rails, you'll instinctively reach for them on test day.