Heart rate predicting the flu

First indications in Tuesday’s body pump session. The 10k warm up run beforehand went fine, no extraordinary observations. In the session the heart rate rarely goes beyond 75% of the maximum heart rate (with me). In the end all exercises are not too dynamic, i.e. the movements are controlled and to 90% slow. But this time the Polar S625x indicated a well beyond 80%, i.e. beyond 160 bpm heart rate when doing squats. All else felt normal, no running nose, no tickling in the throat.

Then, yesterday’s training 5×2000m interval runs came about only half ways. During warm-up the body and especially legs felt tired, but that’s normal after a strength session the day before. It’s generally not optimal to have an interval run training the day after a strength session. That will need to change in the training plan. Anyway, the first 2k run went ok timewise 6:56min, the second however was out of bounds 7:05 and the heart rate closing in on 180. Normally it would stay around 175 on longer interval runs. A slower than expected run and higher than expected pumping of the heart alerted  to no good news the next days.

And as anticipated, this morning head ache, a stuck nose, a sore throat and sweat when lifting things etc. A light flu or bad cold came around.

I’ve heard about this phenomenon that the virus infection is actually happening a couple of days earlier than it’s symptoms show up, hence the heart rate is observably higher under stress/when exercising, but couldn’t find anything on the web.

Anyway, after a lot of tea, I guess it was at least 1,5 liters today, an Aspirin and some additional sleep, the feeling is ok now in the evening. Will observe the heart rate tomorrow closely on the long run.

Tags: flu, flu prediction, heart rate