In Dragon Quest Builders 2 you can run if you want to get around a little more quickly. If you want to run in Dragon Quest Builders 2 you need to use the R1 Button (PS4) or the R Button on Switch. Once you do start running you will see your character open their arms and a small meter will appear below them.
This meter is the amount of time that you can run before you’ll stop being able to. The meter will deplete quickly and once it does you will no longer be able to run until you recover some stamina. Running will deplete your hunger faster than just standing still. However, if you want to get to where you’re going quickly pressing the R1/R button and holding it down is the way to run.
Other than using a little more of your hunger meter, running doesn’t seem to have any other real drawbacks to using it. However, once you have depleted the yellow bar below your character you should give your character some time to rest and let this meter recover before running again as holding down the button will instantly expend any stamina that you recover.