Just had another XP and thought to add in that was in another post.
So my strength went down very minimal after recovering from covid. Mainly this was due to lack of eating because I wasn't as hungry because I wasn't working out at all for 10 days. So the body didn't need the fuel/energy from a high protein/calorie diet. This often happens when I go on vacation, by the 4th day of vacay, I lose my appetite because I don't workout when on vacay. So when we go to Vegas, we hit the buffets early in the trip.
And to get back to where I was b4 vacay it usually takes 3 weeks. Hard to tell with covid because I purposely took things slowly because the effects are unknown. Don't want to come back to hard and end up in the hospital.
Example: Vacay and Covid numbers
Squat pre vacay/covid 405lbs
After vacay/covid 385lbs for the same amount of reps as I did 405lbs. Numbers are about the same for all exercises 5-10% loss of strength.
So compare this to when I get the flu, not only do I have fever, chills, body ache, sleeping for 2-3 days, but also lose 6 months of hard work at the gym. Then when I do go back, it takes me 3 months or so to get back to where I was before catching the flu. Not only does my strength go down big time, but so does my endurance and size. My clothes is noticeably baggier.
Squat pre flu-405lbs
Post flu-345lbs or so. Haven't caught the flu in years, so going by memory. Again number holds true for other exercises as well for reduced strength. The biggest is my flat barbell bench 275lbs to 225lbs for the same amount of reps.
So update after recovering from covid 3 months ago, health has been back to normal, still getting stronger in the gym. Lungs feel fine. This was expected, but since covid is so new, the long term for myself is unknown. But so far, so good.
So in the end with my personal XP with covid, IMO the flu is way worst for me. Not only do I get all the symptoms (see above) of the flu, but my gains in the gym are impacted way more.