The lactate app that turns readings into thresholds
Log in-ride or afterwards. LT1 and LT2 are estimated for you.
ENDURE lets you enter lactate readings while you are still on the bike — or add them later from your ride history — and fits a curve through them to estimate LT1 and LT2 automatically, including a confidence tunnel that shows how well-supported the estimate is. It is the first cycling app to do this inside the ride itself.
What problem does in-app lactate logging solve?
A step test produces two streams of data that normally end up in different places: power and heart rate in your training app, blood values on a scrap of paper that becomes a spreadsheet. Joining them by hand is tedious enough that most riders test once, plot it, and never repeat it. ENDURE removes that friction — the reading is entered against the step you just rode, so the two streams never separate.
How do you log a lactate reading during a ride?
At the end of a step, take your sample as usual and enter the value without leaving the ride screen. The app stamps it against the power you were holding, so the pairing is exact rather than reconstructed later. If you would rather concentrate on the test itself, note the values on paper and add them afterwards from the activity — the result is identical.
How does ENDURE estimate LT1 and LT2?
The app fits a curve through your readings and reads the two thresholds off it: LT1 where lactate first rises meaningfully above your baseline, LT2 where the curve steepens into accumulation. Around the fit sits a confidence tunnel, which is the honest part — three readings give a wide tunnel, eight give a narrow one, and you can see at a glance whether to trust the number or take another sample.
What can you do with LT1 and LT2 once you have them?
Threshold-based zones are the backbone of polarised and pyramidal training. Volume below LT1 builds the aerobic base at low fatigue cost; controlled work at and above LT2 raises the pace you can hold. Because the thresholds are measured rather than derived from a single FTP number, riders with identical FTP get correctly different zones — which is the entire argument for testing in the first place.
Do you need lab equipment?
No. A handheld lactate meter, test strips and a trainer you can hold steady steps on are enough — ERG mode makes those steps precise, which matters more for a usable curve than laboratory hardware does. The guide below walks through a full protocol.
Can I add lactate values after the ride?
Yes. Readings can be entered live during the ride or added later from your activity history, with the same result.
How many readings do I need for a usable LT1 and LT2?
More readings narrow the confidence tunnel around the fitted curve. A graded step test with a handful of samples across a wide enough power range gives a usable estimate; sparse readings produce a visibly wider tunnel, which is your cue that the estimate is soft.
Does ENDURE need a specific lactate meter?
No. You enter the value yourself, so any handheld meter works — ENDURE does not read the device directly.
Log your first test
Free on iOS and Android — in-ride lactate logging, automatic LT1/LT2 estimation, and your power data in the same place.
