1. Use Prophylaxis
No, I'm not suggesting you wear condoms on all your fingers, although, come to think of it, that might not be a bad idea.
I'm suggesting that you keep some of the anti-viral medication Tamiflu on hand and take it before you fly on a plane, which, even in non-cold and flu season, is pretty much a flying test tube that's got the perfect humidity and temperature needed to spawn and incubate all manner of microbial life.
Tamiflu is a prescription item, and taking it prophylactically isn't an approved usage, so you'll need to lean on your doc to get a prescription. Pop one an hour before you even get to the airport (or convention, mass sporting event, etc.). There aren't studies that have looked at its effectiveness in this type of situation, but it makes sense that it would work.
2. When They Go Low, You Go High
While every barbell, dumbbell, battling rope, TRT strap, bench and machine is teeming with bacteria, their bacterial numbers pale in comparison to what you'd find on the door handle to the gym. While only a few numbskulls do the battling ropes, everybody touches the handle or the doorframe immediately above it.
Also, while the equipment at least gets wiped down (presumably) by sullen, unseen workers at night, not so the door. The door handle or frame probably hasn't been polished since it left the door handle factory in Hoboken, New Jersey.
But there's a ridiculously simple way to avoid touching most of those door germs – simply reach high up on the frame and push the door open using your triceps and lats instead of your triceps and chest. The only other people who've touched the door up that high are NBA players and they're all busy playing basketball during cold and flu season.
In fact, do this everywhere you go and I bet you'll avoid a whole lot of sickness.
3. Play Doctor
The CDC says anti-bacterial gels don't work all that well. Using one that's between 60 and 95% alcohol will muck up the lipid cell membranes and the protein walls of most bacteria, but there are no guarantees.
Don't bother with the non-alcohol based sanitizers, either, because they don't work well with all classes of germs and might paradoxically allow other germs to grow unchallenged.
So the answer, as you've heard before but chronically ignored, is to do a heroic job of washing your hands, particularly after you work out. And I'm not talking about one of those hand washes where you pee and then sorta-kinda pass your fingertips through the water and flick the moisture off because you don't want the other dude in the bathroom to think you're an animal.
Scrub them with soap. Work every finger individually. Clean the backs of your hands, too. Take 20 seconds. Pretend you're an obstetrician who has traveled back in time to deliver himself. If you fail to scrub properly, your infant self gets a horrible infection and dies, thus creating a temporal paradox and preventing you from training chest on Monday.
If your only option is to use a hand sanitizer, use a lot and keep rubbing it all over your hands until it's entirely dissipated.
4. These Apples Ain't Healthy
Don't lay your cell phone on any public surface. I don't care if you've got a cool Captain America cell phone case that you want to show off; don't put it down on any bench, floor mat, table, or counter that you can't swear has been drowned in Lysol seconds before you got there.
And despite what I wrote above about the relative ineffectiveness of antibacterial gels, clean that phone – front and back – with a Lysol sanitizing wipe. Do it at least once a day. You'll eliminate most pathogens, along with removing skin cells, mucus, and various proteins that serve as substrates for the various wee beasties.
5. The Pen is Mightier Than the Sword, Especially If It's Coated With Norovirus
If you ever want to get sick, like say you don't want to go to your sister-in-law's kid's bat mitzvah on Wild Card Saturday, go into a doctor's office and sign in using their bacteria-coated pen, the one with the little plastic flower on the end of it that's intended to psychologically mask its lethality.
I swear I fell prey to this last year. I signed into the doctor's office and I got sick in 48 hours, which is exactly the average incubation period for the flu. I now arm myself with my own pen before I go anywhere I might have to sign for something. It's one of those that has a knobby rubber piece on the other end so I can use it for touch screens, too.
It may sound a little too anal, but compared to catching the flu, it's worth the slight feelings of wussiness you might feel in going to such lengths to protect your health.
6. Breathe Like Bikram
Whenever you're on your way to the squat rack and someone who's in the middle of coughing or sneezing up a lung starts walking in your direction, go into yogi mode and breathe out slowly until the bacterial incubator is 6 to 10 feet behind you.
Then quietly turn around and set fire to him or her. If you're in a Planet Fitness-type gym and setting fire to someone is considered lunkish, just do the breathing thing.