Provided is a frame structure particularly useful for bicycles and the like. In one embodiment, the frame structure includes a top, a bottom, a front end and a rear end, a first frame side element and a second frame side element. The first frame side element and the second frame side element are in juxtaposed spaced relationship via a plurality of frame spacer elements and define an inner space between the first frame side element and the second frame side element, each one of the first frame side element and the second frame side element being in the form of a double walled panel.