Most people (without serious medical issues) moaning about a lack of energy know exactly what's causing it but refuse to change their habits. Whether it's drinking, smoking, junk food, staying up late, etc. they've just become too attached to that way of living.
The article wastes a lot of words on basically nothing.
That said, for anybody in a nice city with enough bike lanes, I cannot stress how nice bike commute is for your life. Saving money, time[0], mental energy while restoring health. That a fractal silver bullet for you.
[0] everytime I tried going to work by car or bus, I left home earlier, arrived late at work, and had to pay for gas or tickets. Insane
Put another way: everything is nature, nurture and “random”. It’s rare to find an outcome where one of those three completely dominates the causal equation.
To state my original point in a potentially clearer way: I suspect there is significant genetic variation in energy, controlling for lifestyle habits. Evidence: 1) Personal observation over years of interest in this topic 2) the fact that there is extensive variation in most quantitative life outcomes, controlling for lifestyle habits