The Collaborative International Dictionary of English v.0.48:

Trudge \Trudge\, v. i. [imp. & p. p. Trudged; p. pr. & vb. n.
   Trudging.] [Perhaps of Scand. origin, and originally
   meaning, to walk on snowshoes; cf. dial. Sw. truga, trudja, a
   snowshoe, Norw. truga, Icel. [thorn]r[=u]ga.]
   To walk or march with labor; to jog along; to move wearily.
   [1913 Webster]

         And trudged to Rome upon my naked feet.  --Dryden.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

79 Moby Thesaurus words for "trudging":
   ambling, ambulation, backpacking, cautious, circumspect,
   claudicant, crawling, creeping, creeping like snail, deliberate,
   easy, faltering, flagging, foot-dragging, footing, footing it,
   footwork, gentle, going on foot, gradual, halting, hiking,
   hitchhiking, hitching, hobbled, hobbling, hoofing, idle, indolent,
   languid, languorous, lazy, legwork, leisurely, limping, lumbering,
   marching, moderate, pedestrianism, perambulation, poking, poky,
   relaxed, reluctant, sauntering, shuffling, slack, slothful, slow,
   slow as death, slow as molasses, slow as slow, slow-crawling,
   slow-foot, slow-going, slow-legged, slow-moving, slow-paced,
   slow-poky, slow-running, slow-sailing, slow-stepped, sluggish,
   snail-paced, snaillike, staggering, strolling, tentative, thumbing,
   thumbing a ride, toddling, tortoiselike, tottering, tramping,
   treading, turtlelike, unhurried, waddling, walking