How I Set My Cycling Zones From a 30-Minute FTP Test
By Bryan Collins·Ironman finisher and Norwegian Method practitioner. Writes the first-hand training posts on MyTriathlonCalculator.·Reviewed May 2026
I set my cycling zones from a 30-minute FTP field test, not a 20-minute test and not Garmin's auto-FTP estimate. The 30-minute average power is close enough to true threshold that I can pace Olympic-distance bike legs at 88–94% of it, or 90–95% of threshold heart rate, without blowing up the run.
- •30 minutes all-out on a familiar road — not an indoor ramp.
- •Average power for the full 30 min = working FTP.
- •Olympic race pacing: 88–94% FTP / 90–95% threshold HR.
- •Re-test every 6–8 weeks, or whenever fitness clearly shifts.
Why a 30-minute field test, not a 20-minute one
A 20-minute test multiplied by 0.95 is the popular shortcut, and an indoor ramp test is the convenient one. I do neither for my own training. Twenty minutes is short enough that I can hold a watt number that flatters me; the 0.95 fudge factor was designed for that reason and it still over-reads in my legs. Indoor ramps spike heart rate from heat and a static cabin and tell me more about ventilation than threshold.
Thirty minutes on the road is long enough that I cannot hide. The first ten minutes feel hard, the middle ten feel honest, and the last ten tell me exactly where my sustainable ceiling sits. The average power across the whole effort is my working FTP. No multiplier, no software estimate, no apology.
My April 5, 2023 test
I last ran the protocol on April 5, 2023 on my regular bike, recorded on Garmin, on a stretch of road I know well. Warm-up was easy spinning with two short openers, then 30 minutes flat-out and honest. The ride file and screenshot live in my training archive.
I am not going to post the exact watt average here. It is three years old, my fitness has moved since, and a stale number on a public page is worse than no number at all. The protocol matters more than the result — if you run the same test on the same stretch of road twice, the trend tells you more than any single ride.
The Olympic-distance pacing band I aim for
Most triathletes can sustain 88–94% of FTP, or 90–95% of threshold heart rate, for an Olympic-distance bike leg without compromising the run. That is the band I sit in. I do not race the top of it unless the course is flat and the run is short.
How I split the band by leg length:
- Sprint: top of the band, 92–94% FTP. The run is short enough to survive a slightly cooked bike.
- Olympic: middle of the band, 88–92% FTP. Save legs for a 10K off the bike.
- Olympic with a hilly run: bottom of the band, 86–90% FTP. I would rather give up a minute on the bike than lose five minutes on the run.
Heart rate is the cross-check, not the primary signal. Power tells me what I am doing right now; heart rate tells me what it is costing me.
What this doesn’t replace
A 30-minute FTP test gives me a power number. It does not tell me where my aerobic ceiling (LT1) sits or how much lactate I am clearing at threshold. For that I run a stepped turbo session with a finger-prick lactate meter and watch the curve. I cross-check my FTP-derived zones against that lactate data — if the two disagree by more than a few percent, I trust the lactate session.
That is a separate protocol and a longer post. See my lactate testing post when published.
When I retest
I rerun the 30-minute test in three situations:
- Mid-block: roughly every 6–8 weeks under a Norwegian Method block, because the zones are the thing the whole plan hangs off.
- After a clear fitness shift: a sustained drop in heart rate at the same power, or a sustained jump in power at the same heart rate. Either tells me the old number is lying.
- Pre-race tune-up: three to four weeks out from an A-race, to set race-day numbers from current legs rather than spring legs.
I do not retest because the calendar says so. I retest because my body has clearly moved and the old zones are no longer doing their job.