Do you move clumsily, heavily and slowly, without a shred of grace? Then it sounds like you might lumber. Sorry to hear that.
Lots of other words and phrases are associated with our friend lumber. Particularly large or tall people are almost inevitably said to lumber, as the common phrase "lumbering giant," attests. You never hear of a tip-toeing giant, but some of them must. Lumberjack, meaning someone who cuts down trees, is another. Often lumber, in the sense of planks of wood, is interchangeable with the word timber.