Tracy Duvall

Elsewhere I explain how I use my heart rate (HR) to manage my chronic disease. In this post, I will describe my equipment, which also allows me to monitor my heart-rate variability (HRV). In short, I pair a Garmin Vivoactive 3 smartwatch to a Wahoo Tickr Fit armband; the watch measures HRV well but does a poor job with HR during low-level activity—which is about all I do.

Here are the details, including reasons for not choosing competing products: Continue reading →

One of the basic bits of advice for people with ME/CFS is, “Don’t overdo it.” But, given the delayed reaction of PEM (post-exertional malaise), how can we know whether we’re exerting ourselves too much? Some medical professionals urge patients to monitor their pulse, or heart rate (HR), to stay within their energy envelope. Like many others, I follow this advice. But I believe that the focus on HR, and especially on a specific rate of beats per minute (BPM), is simplistic and actually can lead to ‘overdoing it.’

The first reason to not depend solely on heart rate is that psychological stress can cause PEM, too. This stress can be due to positive or negative situations, and the heart rate doesn’t have to rise as high as it does during overexertion to cause PEM. For example, while teaching a college class for 80 minutes twice a week (my only real activity), I feel low-level excitement, and my HR stays well below the rate that I can sustain for that length. Yet this excitement causes PEM. So exertion isn’t everything. (It would be great if researchers addressed this.)

The rest of this post discusses my approach to managing my exertion using heart rate. I list the equipment I use in another post. Continue reading →