Sentence:  Roger Vaughn explains the tack, in relation to the <WSD>boardsmen</WSD>, stating: "Part of the fun, not to mention exercise, in log canoe sailing smooth crew work with the heavy planks that keep these hulls on their feet or close to it." 
Meaning of the word marked with <WSD> tags:  One who rides on the boards of a log canoe in order to balance it.