David Leonhardt’s July 8 article for The New York Times.com, included a graph that showed if individual states were considered to be countries, Arizona, Florida, and South Carolina would rank first, second, and third in the world for the most new confirmed cases of coronavirus for the previous week. Louisiana, Alabama, Nevada, Mississippi, Texas, and Georgia would all rank in the top 12.

How in the world did the Sun Belt suddenly become “the global virus capital”? Did it happen, perhaps, because of an increased use of air conditioning when the South began to bake?

AC units recirculate a higher percentage of indoor air as the outside temperature increases. They also remove moisture in the air - and viruses thrive in dry environments.

The same week the Sun Belt numbers went sky high, a group of 239 international scientists published a warning in the journal Clinical Infectious Diseases directed at World Health Organization and world governments. It was summarized by one of them, Shelly Miller, PhD at the University of Colorado, in WebMD.com article this way: “We have just as much evidence to show that airborne transmission is happening as is surface transmission.”

Chinese scientists, for instance, just published a paper attributing the transmission of the coronavirus to three separate families seated at different tables in a restaurant to the wall-mounted AC unit. They propose the airflow from it allowed “micro-droplets” expelled from a single asymptomatic person not seated with any of the families to infect all of them.

Now the news you just read is not designed to scare you away from dining indoors. It’s supposed to elicit a certain sensation, one that you have probably felt dozens of other times during the coronavirus pandemic.

The rather unsettling sense of not knowing for sure.

It’s a feeling fraught with doubt that creates indecision, so we rarely seek it out in any situation, health crisis or not. But there’s at least one situation where you should: When you desire to improve your health and fitness in a specific way.

Hear me out on this one.

Being seven months away from starting my seventh decade, I see sarcopenia, the inevitable loss of muscle once you reach middle age and beyond, as my most pressing health concern. So when I read last December about a study where a high daily dose of omega-3 fatty acids mitigated middle-aged muscle loss, I doubled the amount of it I was already taking.

Before I could assess if the extra omega-3s were working, however, I fractured my left femur. After that, I was given a blood thinner for two weeks and advised not to take any supplements for another month afterward just to be safe. I was six weeks into rehabilitation before I resumed the double-dose experiment.

About six weeks after that, I assessed the progress of my rehabilitation using a full-length mirror. It confirmed what the doctor keeps telling me.

Regaining full strength takes a full year.

But something else caught my eye.

The muscles in my arms looked a bit fuller than before the bicycle crash. While the difference may not have amounted to much according to a measuring tape, the triceps clearly had a more discernible horseshoe shape and the usual two-taut-cables look to the biceps seemed to be a bit more pronounced.

Clearly no evidence of sarcopenia here - even though a convalescence such as mine should have engendered it. Was the double dose of omega-3s working?

Or was something else responsible?

During rehabilitation, I didn’t ride the bike as much and certainly not as intensely as before. While I still lifted weights with my upper body, the weights needed to be lighter and the reps higher - not exactly the textbook way to add muscle. I also ate extra protein early in the process to help the break heal as quickly as possible.

For the time being, I was winning the battle against sarcopenia. But how?

I’ve accepted that I’ll never really know for sure. And although I can live with that, I’ve found that many others in similar situations can’t.

Not knowing for sure is why at times you may hesitate to do what I so often urge you to do: experiment with elements of your workouts and diet in an attempt to improve your health and fitness. My sarcopenia story makes something about experimentation clear, however: There’s really no way to account for the other variables.

After all, you’re not a scientist in a laboratory setting.

But don’t let that lack of knowing for sure sap your motivation for experimentation. See those many different variables along with the change you’ve made as members of a firing squad.

When the time comes, all members shoot simultaneously, fully aware that some have been randomly issued blank cartridges. They never know for sure which one of them is responsible for getting the job done.

Only that it got done.