Cycling · 3 min read
Cycling FTP and Lactate Threshold: Which Number Should Guide Training?
FTP is a useful way to organise cycling sessions. A blood lactate profile answers a different question: how your physiological response changes as power rises. Understanding both helps you decide whether a field test is enough or whether a lab assessment would change your training.
By DVOTION Team ·
What an FTP test tells you
Functional threshold power is a practical estimate derived from a cycling performance test. One familiar approach takes 95% of the average power from a 20 minute effort. Your pacing, familiarity with the test and ability to sustain that effort all influence the result.
Repeated under similar conditions, a field test can help you track performance on your own equipment. Record the protocol as well as the watts. Numbers produced by different test formats should not be treated as interchangeable.
What blood lactate adds
A lactate profile records blood lactate alongside increasing workloads. The shape of that response helps identify the first and second lactate thresholds, LT1 and LT2. Those two points give more information about the range of intensities below a hard effort than a single FTP value.
Valenzuela and colleagues compared the 20 minute FTP approach with a laboratory lactate threshold in 20 male cyclists. The measures were closely related, but the agreement differed with training level. That supports using FTP as useful context, while checking individual agreement before treating it as the same physiological measurement.
Choose the test around a decision
If you want a repeatable benchmark for indoor training, a familiar field test may be enough. If easy rides repeatedly become demanding, or threshold sessions do not feel consistent with the prescribed watts, a lactate profile can help you review how those intensities were set.
At DVOTION Labs in London, Endurance Performance Profiling combines a progressive blood lactate profile with a separate maximal aerobic test after recovery. Tell the team that your priority is cycling when arranging the assessment. A running result does not establish your cycling power zones.
Bring the result back to your bike
Review power alongside heart rate and perceived effort during normal rides. A lab bike and your own power meter may not report identical values. Keep a record of the equipment and conditions before interpreting a small difference as a change in fitness.
Use the findings to agree a manageable training change, then review whether sessions are achieving their intended purpose. The useful result is a clearer decision about training, rather than a higher number on its own.
Frequently asked questions
Is cycling FTP the same as LT2?
FTP and LT2 are related concepts obtained through different methods. A field estimate should not automatically be substituted for a laboratory threshold in an individual cyclist.
Can I use running heart rate zones for cycling?
Running and cycling can produce different physiological responses. Use cycling specific results when the purpose is to prescribe cycling sessions.
Where can I arrange cycling lactate testing in London?
Contact DVOTION Labs about cycling Endurance Performance Profiling at its London locations. Confirm the exercise mode and appointment location when arranging the assessment.
References
- Valenzuela PL, Morales JS, Foster C, Lucia A, de la Villa P (2018). Is the Functional Threshold Power a Valid Surrogate of the Lactate Threshold?. International Journal of Sports Physiology and Performance. doi:10.1123/ijspp.2018-0008
Supports: A comparison in 20 male cyclists found that agreement between the 20 minute FTP estimate and lactate threshold differed with training level.
Related assessment
Endurance Performance Profiling