One of my current concerns is that I am currently far, far more unfit than I was a month ago. My regular sources of exercise have been taken away, and whilst I have been trying to compensate - going for a jog or a walk every day and spending a bit of time on my rowing machine (turned out to be a shrewd purchase a few months ago!) doesnt compare to what I normally do and enjoy.
Basically, and without expecting a real answer, it would be interesting to see the correlation (if any) between general fitness levels, and COVID severity. A month ago, it wouldnt have surprised me if I had already caught it and just not noticed, whereas now I feel like it would be a much bigger deal. Now, I am still young enough that I wouldnt consider myself as "vulnerable", but on a mass scale I wonder if taking away everyone's regular sources of exercise counteracts some of the benefits of the lockdown/social distancing.