The point of maneuvering speed (Va) in a seized-wing is that, below that speed, a sudden increase in load-factor (for instance, hitting a sharp updraft) will result in the wing stalling, rather than overstressing the wing. The stall, of course, unloads the wing.
As noted above, helicopters don't have such a speed. The R22 does have in the limitations section of the POH a note concerning moderate or above turbulence. You are to fly between 60KIAS and 0.7Vne, but not lower than 57 KIAS.