WordNet (r) 3.0 (2006):

footslog
    v 1: walk heavily and firmly, as when weary, or through mud;
         "Mules plodded in a circle around a grindstone" [syn:
         slog, footslog, plod, trudge, pad, tramp]

Moby Thesaurus II by Grady Ward, 1.0:

81 Moby Thesaurus words for "footslog":
   amble, backpack, barge, bowl along, bundle, clump, defile, drag,
   file, file off, flounce, foot, go on parade, goose-step, halt,
   hike, hippety-hop, hitch, hobble, hop, jog, jolt, jump, limp,
   lumber, lunge, lurch, march, mince, mush, pace, paddle, parade,
   peg, piaffe, piaffer, plod, prance, rack, roll, sashay, saunter,
   scuff, scuffle, scuttle, shamble, shuffle, sidle, single-foot,
   skip, slink, slither, slog, slop, slouch, stagger, stalk, stamp,
   stodge, stomp, straddle, straggle, stride, stroll, strut, stump,
   swagger, swing, tittup, toddle, toil, totter, traipse, tramp,
   trash, trip, trudge, waddle, wamble, wiggle, wobble