Take the 'Incomparable' as an example:

The law of 3 March 1804 decreed that every battalion of light infantry must contain one company of voltigeurs (lit. ‘vaulters’).
....
By 11 May the voltigeur officers for the field battalions had been appointed. They were captains Janin and Bruyère; lieutenants Collignon and Martinet; and sub-lieutenants Lambert and Petit. The second company of each battalion was dissolved to make room for the new company and the men were exchanged with those who qualified for service with the voltigeurs. The vast majority of the men in the Ninth were above 1.65m in height so the regiment found itself 215 men short of the 360 required and so the remaining places went to short conscripts.

Crowdy, Incomparable Napoleon's 9th Light Infantry Regiment, p. 123-124.