The Collaborative International Dictionary of English v.0.48:

Lustily \Lus"ti*ly\, adv.
   In a lusty or vigorous manner.
   [1913 Webster]

WordNet (r) 3.0 (2006):

lustily
    adv 1: in a healthy manner; "the young plants grew lustily"

Moby Thesaurus II by Grady Ward, 1.0:

47 Moby Thesaurus words for "lustily":
   actively, aloud, animatedly, briskly, con brio, deafeningly,
   energetically, firmly, forcefully, forcibly, forte, fortemente,
   fortissimo, heartily, imperviously, impregnably, in full cry,
   intensely, invincibly, invulnerably, irresistibly, keenly, loud,
   loudly, mightily, noisily, powerfully, pungently, resistantly,
   resoundingly, ringingly, robustly, ruggedly, soundly, spiritedly,
   stalwartly, staunchly, stoutly, strenuously, strongly, sturdily,
   unyieldingly, uproariously, vigorously, vivaciously, with pep,
   zestfully