Introduction

I had COVID in early November and it hit me pretty hard.

On 27th October, I ran a half marathon personal best and was in very good fitness. The first symptoms appeared just over a week later, on 4th November. It started with me feeling a bit off in the evening followed by extreme chills a few hours later, by which time I felt like I had flu. I ended up having a few days in bed that week, but then felt a lot better the following week. However, the week after that I was feeling pretty bad again (though not as bad as the first week) and often feeling very tired. My sleep quality felt poor. I would often wake up in a morning having slept solidly through the night but feeling like I had barely slept at all.

My running ability dropped off massively. Garmin has downgraded its estimation of my v02max from 57 to 51.

I seem to have turned a corner in the past week. I ran the Christmas day Parkrun in 23:14, which was too fast (but still slower than HM pace!) and left me feeling very tired, but then I ran the same Parkrun three days later on the 28th in 22:45 with no after effects (and a lower overall heart rate). New Year's Day and 4th January were at a similar pace, where I seem to have plateaued for the moment. Running is still harder and slower than it should be and my heart rate is definitely a lot higher than it used to be, but at least I'm tolerating an increased exercise load now.

So I'm now 9 weeks post infection am still not fully recovered. The recovery metrics are showing promise, but they are a long way off where they were.

Metrics

The measurable effects this virus has on my body are notable.

My Garmin watch has been tracking my heart rate variability (HRV), resting heart rate (RH) and sleep quality (SQ). RHR is self explanatory. SQ is something Garmin works out with its own proprietary calculation, but obviously higher is better. HRV refers to the variability in the time between heart beats; tying this to health is a relatively new concept and it appears that lower numbers indicate physiological stress, therefore higher is better.

Note: The HRV measurements are given as RMSSD.

I have divided the data into the weeks leading up to infection, starting from July, and the weeks from infection to now (2024-11-04 to 2025-01-05).

Predictably, at infection, my HRV tanked and my RHR shot up. There was then a strange period a few days later where it looked like they were recovering, before they both settled into being significantly worse than my pre-infection averages.

Weekly running volume

As you can see, my weekly running volume fell dramatically as I was infected and only started to show signs of recovery 8 weeks later. I have largely let my body's response to exercise guide this; if I felt bad I didn't run, if I felt good, I did. I generally didn't run two days in a row until late December, and I would often limit runs to 20 minutes at a pace far slower than my previous zone 2 pace, (often with a zone 4 heart rate).

Note: Weeks 2024-08-05 — 2024-08-12, and 2024-10-21 — 2024-10-28 were tapering for and recovery from Solihull and Stratford half marathons.

I was hoping to get the final week's (2024-12-30) distance a bit higher with a 10km run on Sunday, but snow and ice put a stop to that.

Heart rate variability

HRV looks like it's recovering now, but my current highs are still at the lower end of my previous readings. Note the sudden drop from 59ms to 36ms on 26th December after I did a fast Parkrun on the 25th.

Resting heart rate

My resting heart rate shows a less dramatic difference than HRV, but it's still very noticeable.

As with HRV, note the sudden jump from 47bpm to 53bpm on 26th December after I did a fast Parkrun on the 25th.

Sleep quality

I don't generally pay a lot of attention to Garmin's sleep analysis because I've always been a bit sceptical that it really knows as much as it claims, but it does tend to match my perception of my sleep quality. For quite a few weeks post infection I was feeling tired most of the time and waking up in a morning after a solid 8+ hours of sleep feeling like I'd barely had any sleep. In recent weeks I'm feeling like I'm sleeping normally again. Garmin sort of agrees with this - there's a lot of variance in my sleep quality immediately post infection, and, as I've started to feel better rested in recent weeks, it has been consistently scoring me higher with fewer and less pronounced drops.

I suspect the regular big drops pre-infection correspond to hard workout days (I rarely sleep well on a given night if I've done a hard aerobic workout in the afternoon/evening).

Data