A protective textile sleeve and method of construction thereof are provided. The sleeve has a tubular wall of braided yarns extending lengthwise along a central longitudinal axis between opposite ends. At least some of the braided yarns including heat-set yarns, and the wall has a plurality of annular first regions forming generally convex ridges and a plurality of annular second regions forming generally concave valleys. The first regions alternate with the second regions along the central longitudinal axis. The first regions include a plurality of twisted yarns forming a plurality of closed loops, wherein at least some of the braided yarns pass through at least some of the closed loops within the first regions to enhance the radial stiffness and resistance of the wall to kinking.