Another wasted day caused by overactivity exacerbated by the effects of a lingering flu virus have caused me to take my pacing a bit more seriously. (This slightly alarming review article in the International Journal of Cardiology also helped to motivate me.)
The phenomenon known as Post-exertional neuroimmune exhaustion – as illustrated in this series of articles – not only cruelly reverses the usually beneficial effect of exercise, but lessens the heart’s already compromised capacity to circulate blood around the body. This is why patients who have over-exerted themselves, whether by walking too far or even just climbing the stairs, have palpitations at rest, which is an uncomfortable and sometimes frightening experience. This also has long-term implications, as the review article quoted above points out there is a high mortality rate among ME patients due to heart disease.
One way to reduce the damage caused by repeated flare-ups is to monitor the Anaerobic Threshold – the heart rate beyond which the damage occurs. The methods for this are shown here , but in general the calculation is (220 – [your age]) x .6. Observing the heart rate and ensuring it does not go above a certain level is a difficult task, which is why I am considering the purchase of a heart rate monitor. I am open to suggestions of relatively cheap ones if anyone has experience of this.