Read the following excerpt from theodore dreiser's "my brother paul." based on its context in the excerpt, what is the meaning of the word lithesome?

imagine, if you can, a man weighing all of three hundred pounds, not more than five feet ten-and-one-half inches in height and yet of so lithesome a build that he gave not the least sense of either undue weight or lethargy. his temperament, always ebullient and radiant, presented him as a clever, eager, cheerful, emotional and always highly illusioned person with so collie-like a warmth that one found him compelling interest and even admiration. easily cast down at times by the most trivial matters, at others, and for the most part, he was so spirited and bubbly and emotional and sentimental that your fiercest or most gloomy intellectual rages or moods could scarcely withstand his smile.