Fast-laning is when you rush along on the very outer part of the sidewalk or walkway. Outside of the parking meters, outside the planters, the bike-racks, hydrants, mailboxes, scaffolding- likely treating the curb like a balance beam, eyes peeled for animal droppings and automobiles. Even the best planners occasionally find themselves in a rush and if the powerwalk trajectory is congested by stuck-together saunterers and other slow pokery— fastlaning, even if just to pass some crowded clumps, is something we’ve all done. 
Fast-laning : Advanced Walking Technique number one