I'll often get pretty sore after most strong workouts regardless of what shape I seem to be in. Something I learned from my cycling days - post exercise, lie flat on your back with your legs straight up against a wall, then massage your thighs downwards for about twenty minutes or so. The idea is that the massage along with gravity encourages the lactic acid buildups to be removed from the muscle, which is what makes you sore to begin with. Dunno if there's truth to this or not, but it seems to work for me.