This is my first time in this thread and I saw a few posts asking about estimating LT1 and LT2.
I've done over 2,000 lactate tests in the past 2 years. A few things that I have learned that others might find helpful. Apologies if some of this has already been covered.
Lactate is a great tool but you need to know how to use it. I've seen some horrible testing protocols from lactate tests performed in labs. Improper warm-up, testing from the same location without cleaning the area, and using strict numbers like 2.0 for LT1 and 4.0 for LT2.
Something that has caught me off guard is how insane the individual differences are between athletes. For example, here are two athletes whom I have regularly tested over the past year.
Athlete A will hit 3.0mmol/l at right around 6:20-6:30/Mile and Athlete B will hit 3.0mmol/l at 5:50-6:00/Mile. Obviously, I'm doing this to prove a point, so you probably already know that Athlete A is faster than Athlete B, but what's shocking is the gap between them. Athlete A has run 15:00 for 5k and Athlete B has run 17:40 for 5k.
In my experience there’s no single definite way to determine threshold pace, so I use a combination of methods.
Lactate: Ramp test, testing in session, MLSS and track numbers over time. Lactate testing in session helps athletes learn RPE.
1 hour race pace: This is good to get a general idea of your threshold pace but individual differences in TTE make this unreliable. NEVER use a 5k or shorter race distance in a running calculator to find your 1 hour race pace. Running calculators typically overestimate threshold pace.
Breathing/talk test: Not reliable in my experience. This includes the new Tymewear device. The Tymewear device can be helpful to track continuous data, but I would not use it as a standalone metric.
Effort: If an athlete is honest about their effort level, this is a great way to identify threshold.
Heart Rate: Helpful to look at continuous data, but would not use it to guide threshold workouts.
My advice to athletes is not to over index on any single metric. Use a variety of tools and experiment.