Health benefits of riding.

Is it just me or does anyone else on this group notice that they almost
never get 'sick'. All the riding/exercise/fitness seems to boost the
immune system somehow. Everytime there is some new bug going around
I never get it. I have only been down for the count 3 times in 25+
years, 1977 (food poisoning), 1978 (flu, 106 temp), 1986 (Salmonella,
food poisoning again, from a food truck at work). Other times when
everyone else is down and out I just notice that "Geesh, this hill
got steeper" or something like that. Maybe I will only ride 20 miles
instead of 50 before getting tired/bored(?)/demotivated, but I don't
get sick or bedridden like everyone else.
It could be one of 3 things.
1. Riding and staying in shape.
2. Lucky genes inherited.
3. Not being a germaphobe. I drink out of irrigation canals and mountain
streams and never worry about it so I may be just flexing my
immune system a bit more than others.
Number 3 not recommended for anyone else.
Thoughts?
Bill Baka
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