Source : Webster's Revised Unabridged Dictionary (1913)

Invigorate \In*vig"or*ate\, v. t. [imp. & p. p. {Invigorated};
   p. pr. & vb. n. {Invigorating}.] [Pref. in- in + vigor.]
   To give vigor to; to strengthen; to animate; to give life and
   energy to.

         Christian graces and virtues they can not be, unless
         fed, invigorated, and animated by universal charity.
                                                  --Atterbury.

   Syn: To refresh; animate; exhilarate; stimulate.

Source : WordNet®

invigorating
     adj : imparting strength and vitality; "the invigorating mountain
           air" [ant: {debilitating}]