[Seth Keena]

Hi SlowAndSteady,

Thanks for writing in. Firstly, great job improving your AeT and by so many beats!

Did you also do a drift test around the time you found 2mmol/L at 145bpm?

Were you especially fatigued the day of this high-drift walk?

If this high-drift walk was anomalous I would ignore it as just that; an anomaly. It seems that way to me from where I sit. Even with clean, fresh battery chest straps and excellent GPS data I see HR in places it otherwise ‘shouldn’t be’ on not too rare occasions.  Perhaps do another drift test on a treadmill at 115bpm and see what happens.

Drift tests, lactate test and gas exchange tests are all proxies for aerobic threshold and fitness. We have come to prefer the drift test over the other testing means for its excellent specificity and reproducibility. Nose breathing is also a fine method for observation and control. If you’ve not read our most updated article on this subject area : https://evokeendurance.com/our-latest-thinking-on-aerobic-assessment-for-the-mountain-athlete/

-Seth