not sure what you mean by "the backs of your legs"? were the back of your thighs sore?....as in muscle soreness?....or was it higher up where the backs of your thighs hit the saddle? I sit on my sit bones which rest right about where the saddle "flares". Even in the drops I don't sit on my pubic bones. Sounds like you might need to try out some new saddles - and don't worry, we've All been there done that!