A dense travel calendar wears people down slowly, then all at once. The professionals who sustain it are not superhuman. They protect a few basic routines that keep energy steady when everything else is in motion.
Anchor movement, water, and sleep. A short walk after landing resets your body, steady hydration counters dry cabins, and guarding your sleep window matters more than any productivity hack. When those three hold, the rest of the trip is manageable.
Lower the bar on perfect and aim for consistent. You will not hit an ideal routine on the road, but small, repeatable habits beat an ambitious plan you abandon by day two.