I'm posting here in response to a comm
ent on Cort's recent article on Dr. Lapp's retirement
in which Dr. Lapp stated that "the most important aspect of management is pacing (balancing rest with activity)..." and "That’s when we started working with Staci Stevens, Chris Snell, Mark VanNess, etc., to discover that the anaerobic threshold (AT) was key. Thereafter, we learned to keep PWCs within their AT to prevent flares and relapses."
An HR commenter asked if someone could explain “anaerobic avoidance strategy” vs. "aerobic threshold". I think this is the relevant thread in which to post a response. Here's my 2 cents.
It is common to get confused re: anaerobic vs. aerobic. This is my (non-physiologist!) understanding:
First, definitions: ANAEROBIC means 'without oxygen', whereas AEROBIC means 'with oxygen'.
There are actually TWO different types of ANAEROBIC energy that come into play when one engages in an activity. The first type of ANAEROBIC activity is when we initially engage in an activity. It is normal to use this type of anaerobic system. It is ONLY used for up to the first 2 minutes
of an activity, at which point AEROBIC energy kicks in. This is normal for people who are healthy or who have other diseases, who can then go on to use their aerobic systems all day long. However, for PWME's (people with ME/CFS), the aerobic system is broken
. Instead of using AEROBIC energy (even for what would be low-exertion, minor activities for a healthy person - or a person with another disease), our bodies go into ANAEROBIC metabolism, sometimes after only a few minutes
No-one can stay in ANAEROBIC metabolism for very long -- nor without physical cost (e.g. witness a healthy marathon runner at the finish line) -- and PWME's have a severe, lengthy, prolonged cost - in the form of PEM (post-exertional malaise). PWME's want to avoid PEM as much as possible, of course (even though it's often unavoidable -- like going to a doctor appointment, or making a meal, taking a shower, etc.).
The point at which we go into ANAEROBIC metabolism can be measured using the heart rate. It's called HR at the ANAEROBIC THRESHOLD (HR @ AT). This can ONLY be definitively measured if you undergo a cardiopulmonary exercise test (CPET). Importantly, if you are a PWME, your HR @ AT can ONLY be definitely measured by a 2-day CPET (2 tests on consecutive days, not just one test on one day). Staci Stevens, the founder of Workwell Foundation, who discovered PWME's inability to reproduce physiologic measures on the 2nd day of a CPET, can do this test for you, as can Betsy Keller (Ithaca, NY). The HR @ AT measure for PWME's can drop - sometimes by a LOT - on the Day 2 test, so you want to know your Day 2 measure.
Without the benefit of a 2-day CPET, I have read Mark VanNess (also of Workwell Foundation) state that a general guideline for PWME's is to at least stay under a heart rate of 110 BPM. PWME's can have a HR @ AT much lower than that. To know what your heart rate is, PWME's should wear a heart rate monitor (one that continuously measures your heart rate, plus has an alarm that sounds when you reach your HR @ AT -- that you pre-set).
An additional way to monitor your level of exertion is to use the Borg Scale for Rate of Perceived Exertion -- PWME's want to stay under 13 on this scale (which feels like "somewhat light" exertion).
If this is about as clear as mud, I recommend you check out the Resources section on the Workwell Foundation website.
In particular, check out the 2nd YouTube video down: "How to do more with less: Staci Stevens
". The entire video is very useful, but if you go to the 32:11 minute mark
, Staci explains the ANAEROBIC and AEROBIC energy systems with a great graph (which cleared up the confusion for me!). And if you go to the 42:03 minute mark
, Staci explains the "Rate of Perceived Exertion" with an excellent colour-coded chart (which I recommend printing out!).
I hope this helps.