Hey i never thought about it that way. But seeing as you're pushing your legs to make the swing go it would make sense that they got some exercise out of it.
Cool. I gotta try it!! =)
maybe it gives your calfes a work out but , not your thighs // i think i have fat thighs too ); but i went online and they sayed squattes are the best thing for thigh thinners , also a pool , and a treddmill for fast and afficant fatt loss