Most comfort issues are preventable
Hydration, sun protection, realistic pacing and choosing busy food vendors reduce the most common travel discomforts.
The goal is not to sanitize the trip, but to keep enough energy for the parts of Vietnam you actually came to enjoy.
Rest matters on transit-heavy itineraries
Back-to-back flights, trains and early pickups can wear travelers down faster than sightseeing itself.
If you schedule recovery time between long transfers, you usually end up seeing more and enjoying it more.